Genome mosaicism in field strains of < em > Mycoplasma bovis < /em > as footprints of in-host horizontal chromosomal transfer
This study provides evidence that MCT can take place in the field, most likely during co-infections by multiple strains. Because mobile genetic elements (MGEs) are classical contributors of genome plasticity, the presence of phages, insertion sequences (ISs) and ICEs was also investigated. Data revealed that these elements are widespread within the M. bovis species and evidenced classical horizontal transfer of phages and ICEs in addition to MCT. These events contribute to wide-genome diversity and reorganization within this species and may have a tremendous impact on diagnostic and disease control. IMPORTANCE Mycoplasma b...
Source: Applied and Environmental Microbiology - October 20, 2021 Category: Microbiology Authors: Ana Garc ía-Galán Eric Baranowski Marie-Claude Hygonenq Mathilda Walch Guillaume Croville Christine Citti Christian De la Fe Laurent-Xavier Nouvel Source Type: research

Brussowvirus SW13 requires a cell surface-associated polysaccharide to recognise its < em > Streptococcus thermophilus < /em > host
Appl Environ Microbiol. 2021 Oct 20:AEM0172321. doi: 10.1128/AEM.01723-21. Online ahead of print.ABSTRACTFour bacteriophage insensitive mutants (BIMs) of the dairy starter bacterium Streptococcus thermophilus UCCSt50 were isolated following a challenge with the Brussowvirus SW13. The BIMs displayed an altered, sedimentation phenotype. Whole genome sequencing and comparative genomic analysis of the BIMs uncovered mutations within a family-2-glycosyltransferase-encoding gene (orf06955UCCSt50) located within the variable region of the cell wall-associated rhamnose-glucose polymer (Rgp) biosynthesis locus (designated here as t...
Source: Applied and Environmental Microbiology - October 20, 2021 Category: Microbiology Authors: Katherine Lavelle Irina Sadovskaya Evgeny Vinogradov Philip Kelleher Gabriele A Lugli Marco Ventura Douwe van Sinderen Jennifer Mahony Source Type: research

< em > Coprinopsis cinerea < /em > uses laccase Lcc9 as a defense strategy to eliminate oxidative stress during fungal-fungal interactions
Appl Environ Microbiol. 2021 Oct 20:AEM0176021. doi: 10.1128/AEM.01760-21. Online ahead of print.ABSTRACTFrequently, laccases are triggered during fungal cocultivation for overexpression. The function of these activated laccases during coculture has not been clarified. Previously, we reported that Gongronella sp. w5 (w5) (Mucoromycota, Mucoromycetes) specifically triggered the laccase Lcc9 overexpression in Coprinopsis cinerea (Basidiomycota, Agaricomycetes). To systematically analyze the function of the overexpressed laccase during fungal interaction, C. cinerea mycelia before and after the initial Lcc9 overexpression wer...
Source: Applied and Environmental Microbiology - October 20, 2021 Category: Microbiology Authors: Juanjuan Liu Can Peng Qiqi Han Mengyao Wang Gang Zhou Bin Ye Yazhong Xiao Zemin Fang Ursula K ües Source Type: research

Colibrimycins, novel halogenated hybrid PKS-NRPS compounds produced by < em > Streptomyces < /em > sp. CS147
Appl Environ Microbiol. 2021 Oct 20:AEM0183921. doi: 10.1128/AEM.01839-21. Online ahead of print.ABSTRACTThe improvement on genome sequencing techniques has brought to light the biosynthetic potential of actinomycetes due to the high number of gene clusters they present compared to the number of known compounds. Genome mining is a recent strategy in the search for novel bioactive compounds, which involves the analysis of sequenced genomes to identify uncharacterized natural product biosynthetic gene clusters, many of which are cryptic or silent under laboratory conditions, and to develop experimental approaches to identify...
Source: Applied and Environmental Microbiology - October 20, 2021 Category: Microbiology Authors: Laura Prado-Alonso Ignacio P érez-Victoria M ónica G Malmierca Ignacio Montero Elisa Rioja-Blanco Jes ús Martín Fernando Reyes Carmen M éndez Jos é A Salas Carlos Olano Source Type: research

Spt20, a structural subunit of the SAGA complex, regulates biofilm formation, asexual development, and virulence of < em > Aspergillus fumigatus < /em >
In this study, Spt20, an orthologue of the subunit of Saccharomyces cerevisiae transcriptional co-activator Spt-Ada-Gcn5-acetyltransferase (SAGA) complex, was identified as a regulator of biofilm formation and asexual development in A. fumigatus. The loss of spt20 caused severe defects in GAG biosynthesis, biofilm formation, conidiation, and virulence of A. fumigatus. RNA-sequence data demonstrated that Spt20 positively regulates the expression of GAG biosynthesis genes uge3 and agd3, developmental regulator medA, and genes involved in the conidiation pathway. Moreover, more than 10 subunits of the SAGA complex (known from...
Source: Applied and Environmental Microbiology - October 20, 2021 Category: Microbiology Authors: Yuan Chen James I P Stewart Shuai Liu Donald C Sheppard Ling Lu Shizhu Zhang Source Type: research

Arbuscular mycorrhizal tree communities have greater soil fungal diversity and relative abundances of saprotrophs and pathogens compared to ectomycorrhizal tree communities
Appl Environ Microbiol. 2021 Oct 20:AEM0178221. doi: 10.1128/AEM.01782-21. Online ahead of print.ABSTRACTTrees associating with different mycorrhizas often differ in their effects on litter decomposition, nutrient cycling, soil organic matter (SOM) dynamics, and plant-soil interactions. For example, due to differences between arbuscular mycorrhizal (AM) and ectomycorrhizal (ECM) tree leaf and root traits, ECM-associated soil has slower rates of C and N cycling and lower N availability compared to AM-associated soil. These observations suggest many groups of non-mycorrhizal fungi should be affected by the mycorrhizal associ...
Source: Applied and Environmental Microbiology - October 20, 2021 Category: Microbiology Authors: Andrew C Eagar Ryan M Mushinski Amber L Horning Kurt A Smemo Richard P Phillips Christopher B Blackwood Source Type: research

Utilization efficiency of human milk oligosaccharides by human-associated < em > Akkermansia < /em > is strain-dependent
Appl Environ Microbiol. 2021 Oct 20:AEM0148721. doi: 10.1128/AEM.01487-21. Online ahead of print.ABSTRACTAkkermansia muciniphila are mucin degrading bacteria found in the human gut and are often associated with positive human health. However, despite being detected as early as one month of age, little is known about the role of Akkermansia in the infant gut. Human milk oligosaccharides (HMOs) are abundant components of human milk and are structurally similar to the oligosaccharides that comprise mucin, the preferred growth substrate of human-associated Akkermansia. A limited subset of intestinal bacteria has been shown to ...
Source: Applied and Environmental Microbiology - October 20, 2021 Category: Microbiology Authors: Estefani Luna Shanthi G Parkar Nina Kirmiz Stephanie Hartel Erik Hearn Marziiah Hossine Arinnae Kurdian Claudia Mendoza Katherine Orr Loren Padilla Katherine Ramirez Priscilla Salcedo Erik Serrano Biswa Choudhury Mousumi Paulchakrabarti Craig T Parker Ste Source Type: research

Two TonB-dependent transporters in < em > Methylosinus trichosporium < /em > OB3b are responsible for uptake of different forms of methanobactin and are involved in the canonical 'copper switch'
In this study, we demonstrate that different TonB-dependent transporters (TBDTs) in the model methanotroph Methylosinus trichosporium OB3b are responsible for uptake of either endogenous MB or exogenous MB. Interestingly, the presence of exogenous MB induces expression of its specific TBDT in M. trichosporium OB3b, suggesting that this methanotroph is able to actively take up MB produced by others. This work contributes to our understanding of how microbes collect and compete for copper, and also helps inform how such uptake coordinates the expression of different forms of methane monooxygenase. Such studies are likely to ...
Source: Applied and Environmental Microbiology - October 20, 2021 Category: Microbiology Authors: Peng Peng Christina S Kang-Yun Jin Chang Wenyu Gu Alan A DiSpirito Jeremy D Semrau Source Type: research

Isolation, identification, and characterization of lignocellulose-degrading < em > Geobacillus thermoleovorans < /em > from Yellowstone National Park
In this study, results obtain from G. thermolerovorans isolates originating from YNP springs are significant as very few microorganisms from alkaline thermal environments have been discovered to have lignin and cellulose biodegrading capabilities, and this work opens new avenues for the biotechnological valorization of lignocellulosic biomass at an industrial scale.PMID:34669438 | DOI:10.1128/AEM.00958-21 (Source: Applied and Environmental Microbiology)
Source: Applied and Environmental Microbiology - October 20, 2021 Category: Microbiology Authors: Margaux M Mesl é Rebecca C Mueller Jesse Peach Brian Eilers Brian P Tripet Brian Bothner Val érie Copié Brent M Peyton Source Type: research

< em > Streptomyces coelicolor < /em > vesicles: many molecules to be delivered
In conclusion, this analysis provides detailed information on S. coelicolor MVs under basal conditions and corresponding content, which may be useful in a next future to elucidate vesicle biogenesis and functions. Importance Streptomycetes are widely distributed in nature, and they are characterized by a complex life cycle that involves morphological differentiation. They are very relevant in industry because they produce about a half of the antibiotics used clinically and other important pharmaceutical products having natural origin. Streptomyces coelicolor is a model organism for the study of bacterial differentiation an...
Source: Applied and Environmental Microbiology - October 20, 2021 Category: Microbiology Authors: Teresa Faddetta Giovanni Renzone Alberto Vassallo Emilio Rimini Giorgio Nasillo Gianpiero Buscarino Simonpietro Agnello Mariano Licciardi Luigi Botta Andrea Scaloni Antonio Palumbo Piccionello Anna Maria Puglia Giuseppe Gallo Source Type: research

Competitive exclusion of phytopathogenic < em > Serratia marcescens < /em > from squash bug vectors by the gut endosymbiont < em > Caballeronia < /em >
Appl Environ Microbiol. 2021 Oct 20:AEM0155021. doi: 10.1128/AEM.01550-21. Online ahead of print.ABSTRACTMany insects harbor microbial symbiotic partners that offer protection against pathogens, parasitoids, and other natural enemies. Mounting evidence suggests that these symbiotic microbes can play key roles in determining infection outcomes in insect vectors, making them important players in the quest to develop novel vector control strategies. Using the squash bug Anasa tristis, we investigated how the presence of Caballeronia symbionts affected the persistence and intensity of phytopathogenic Serratia marcescens within...
Source: Applied and Environmental Microbiology - October 20, 2021 Category: Microbiology Authors: Sandra Y Mendiola Kayla S Stoy Susanne DiSalvo Cameron L Wynn David J Civitello Nicole M Gerardo Source Type: research

Cytochrome OmcS is not essential for extracellular electron transport via conductive pili in < em > Geobacter sulfurreducens < /em > strain KN400
Appl Environ Microbiol. 2021 Oct 20:AEM0162221. doi: 10.1128/AEM.01622-21. Online ahead of print.ABSTRACTThe multi-heme c-type cytochrome OmcS is one of the central components for extracellular electron transport in Geobacter sulfurreducens strain DL-1, but its role in other microbes, including other strains of G. sulfurreducens is currently a matter of debate. Therefore, we investigated the function of OmcS in G. sulfurreducens strain KN400, which is even more effective in extracellular electron transfer than strain DL-1. We found that deleting omcS from strain KN400 did not negatively impact the rate of Fe(III) oxide red...
Source: Applied and Environmental Microbiology - October 20, 2021 Category: Microbiology Authors: Xinying Liu Dawn E Holmes David J F Walker Yang Li David Meier Samantha Pinches Trevor L Woodard Jessica A Smith Source Type: research

Specialized Metabolite Mediated Predation Defense in the Marine Actinobacterium < em > Salinispora < /em >
Appl Environ Microbiol. 2021 Oct 20:AEM0117621. doi: 10.1128/AEM.01176-21. Online ahead of print.ABSTRACTThe obligate marine actinobacterial genus Salinispora has become a model organism for natural product discovery, yet little is known about the ecological functions of the compounds produced by this taxon. The aims of this study were to assess the effects of live cultures and culture extracts from two Salinispora species on invertebrate predators. In choice-based feeding experiments using the bacterivorous nematode Caenorhabditis elegans, live cultures of both Salinispora species were less preferred than E. coli. When gi...
Source: Applied and Environmental Microbiology - October 20, 2021 Category: Microbiology Authors: Robert N Tuttle Greg W Rouse Gabriel Castro-Falc ón Chambers C Hughes Paul R Jensen Source Type: research

Predation strategies of the bacterium < em > Bdellovibrio bacteriovorus < /em > result in overexploitation and bottlenecks
Appl Environ Microbiol. 2021 Oct 20:AEM0108221. doi: 10.1128/AEM.01082-21. Online ahead of print.ABSTRACTWith increasing antimicrobial resistance, alternatives for treating infections or removing resistant bacteria are urgently needed, such as the bacterial predator Bdellovibrio bacteriovorus or bacteriophage. Therefore, we need to better understand microbial predator-prey dynamics. We developed mass-action mathematical models of predation for chemostats, which capture the low substrate concentration and slow growth typical for intended application areas of the predators such as wastewater treatment, aquaculture or the gut...
Source: Applied and Environmental Microbiology - October 20, 2021 Category: Microbiology Authors: J Kimberley Summers Jan-Ulrich Kreft Source Type: research

Engineering a lysin with intrinsic antibacterial activity (LysMK34) with cecropin A enhances its antibacterial properties against < em > Acinetobacter baumannii < /em >
Appl Environ Microbiol. 2021 Oct 20:AEM0151521. doi: 10.1128/AEM.01515-21. Online ahead of print.ABSTRACTBacteriophage-encoded lysins are increasingly reported as alternatives to combat Acinetobacter baumannii infections for which limited therapeutic options are available. Some lysins such as LysMK34 have a C-terminal amphipathic helix allowing them to penetrate the otherwise impermeable outer membrane barrier. Another approach to kill Gram-negative pathogens with lysins relies on fusion of a peptide with outer membrane permeabilizing properties to the lysin. In this work, we aimed to leverage the intrinsic antibacterial a...
Source: Applied and Environmental Microbiology - October 20, 2021 Category: Microbiology Authors: Karim Abdelkader Diana Guti érrez H éctor Tamés-Caunedo Patricia Ruas-Madiedo Amal Safaan Ahmed S Khairalla Yasser Gaber Tarek Dishisha Yves Briers Source Type: research

Wildlife symbiotic bacteria are indicators of the health status of the host and its ecosystem
Appl Environ Microbiol. 2021 Oct 20:AEM0138521. doi: 10.1128/AEM.01385-21. Online ahead of print.ABSTRACTLactic acid bacteria (LAB) are gut symbionts that can be used as a model to understand the host-microbiota crosstalk under unpredictable environmental conditions such as wildlife ecosystems. The aim of this study was to determine whether viable LAB can be informative of the health status of wild boar populations. We monitored the genotype and phenotype of LAB based on markers that included safety and phylogenetic origin, antibacterial activity and immunomodulatory properties. A LAB profile dominated by lactobacilli appe...
Source: Applied and Environmental Microbiology - October 20, 2021 Category: Microbiology Authors: Maria Bravo Theo Combes Fernando Martinez-Estrada David Risco Pilar Gon çalves Waldo Garcia-Jimenez Rosario Cerrato Pedro Fernandez-Llario Jorge Gutierrez-Merino Source Type: research

Genome mosaicism in field strains of < em > Mycoplasma bovis < /em > as footprints of in-host horizontal chromosomal transfer
This study provides evidence that MCT can take place in the field, most likely during co-infections by multiple strains. Because mobile genetic elements (MGEs) are classical contributors of genome plasticity, the presence of phages, insertion sequences (ISs) and ICEs was also investigated. Data revealed that these elements are widespread within the M. bovis species and evidenced classical horizontal transfer of phages and ICEs in addition to MCT. These events contribute to wide-genome diversity and reorganization within this species and may have a tremendous impact on diagnostic and disease control. IMPORTANCE Mycoplasma b...
Source: Applied and Environmental Microbiology - October 20, 2021 Category: Microbiology Authors: Ana Garc ía-Galán Eric Baranowski Marie-Claude Hygonenq Mathilda Walch Guillaume Croville Christine Citti Christian De la Fe Laurent-Xavier Nouvel Source Type: research

Brussowvirus SW13 requires a cell surface-associated polysaccharide to recognise its < em > Streptococcus thermophilus < /em > host
Appl Environ Microbiol. 2021 Oct 20:AEM0172321. doi: 10.1128/AEM.01723-21. Online ahead of print.ABSTRACTFour bacteriophage insensitive mutants (BIMs) of the dairy starter bacterium Streptococcus thermophilus UCCSt50 were isolated following a challenge with the Brussowvirus SW13. The BIMs displayed an altered, sedimentation phenotype. Whole genome sequencing and comparative genomic analysis of the BIMs uncovered mutations within a family-2-glycosyltransferase-encoding gene (orf06955UCCSt50) located within the variable region of the cell wall-associated rhamnose-glucose polymer (Rgp) biosynthesis locus (designated here as t...
Source: Applied and Environmental Microbiology - October 20, 2021 Category: Microbiology Authors: Katherine Lavelle Irina Sadovskaya Evgeny Vinogradov Philip Kelleher Gabriele A Lugli Marco Ventura Douwe van Sinderen Jennifer Mahony Source Type: research

< em > Coprinopsis cinerea < /em > uses laccase Lcc9 as a defense strategy to eliminate oxidative stress during fungal-fungal interactions
Appl Environ Microbiol. 2021 Oct 20:AEM0176021. doi: 10.1128/AEM.01760-21. Online ahead of print.ABSTRACTFrequently, laccases are triggered during fungal cocultivation for overexpression. The function of these activated laccases during coculture has not been clarified. Previously, we reported that Gongronella sp. w5 (w5) (Mucoromycota, Mucoromycetes) specifically triggered the laccase Lcc9 overexpression in Coprinopsis cinerea (Basidiomycota, Agaricomycetes). To systematically analyze the function of the overexpressed laccase during fungal interaction, C. cinerea mycelia before and after the initial Lcc9 overexpression wer...
Source: Applied and Environmental Microbiology - October 20, 2021 Category: Microbiology Authors: Juanjuan Liu Can Peng Qiqi Han Mengyao Wang Gang Zhou Bin Ye Yazhong Xiao Zemin Fang Ursula K ües Source Type: research

Colibrimycins, novel halogenated hybrid PKS-NRPS compounds produced by < em > Streptomyces < /em > sp. CS147
Appl Environ Microbiol. 2021 Oct 20:AEM0183921. doi: 10.1128/AEM.01839-21. Online ahead of print.ABSTRACTThe improvement on genome sequencing techniques has brought to light the biosynthetic potential of actinomycetes due to the high number of gene clusters they present compared to the number of known compounds. Genome mining is a recent strategy in the search for novel bioactive compounds, which involves the analysis of sequenced genomes to identify uncharacterized natural product biosynthetic gene clusters, many of which are cryptic or silent under laboratory conditions, and to develop experimental approaches to identify...
Source: Applied and Environmental Microbiology - October 20, 2021 Category: Microbiology Authors: Laura Prado-Alonso Ignacio P érez-Victoria M ónica G Malmierca Ignacio Montero Elisa Rioja-Blanco Jes ús Martín Fernando Reyes Carmen M éndez Jos é A Salas Carlos Olano Source Type: research

Spt20, a structural subunit of the SAGA complex, regulates biofilm formation, asexual development, and virulence of < em > Aspergillus fumigatus < /em >
In this study, Spt20, an orthologue of the subunit of Saccharomyces cerevisiae transcriptional co-activator Spt-Ada-Gcn5-acetyltransferase (SAGA) complex, was identified as a regulator of biofilm formation and asexual development in A. fumigatus. The loss of spt20 caused severe defects in GAG biosynthesis, biofilm formation, conidiation, and virulence of A. fumigatus. RNA-sequence data demonstrated that Spt20 positively regulates the expression of GAG biosynthesis genes uge3 and agd3, developmental regulator medA, and genes involved in the conidiation pathway. Moreover, more than 10 subunits of the SAGA complex (known from...
Source: Applied and Environmental Microbiology - October 20, 2021 Category: Microbiology Authors: Yuan Chen James I P Stewart Shuai Liu Donald C Sheppard Ling Lu Shizhu Zhang Source Type: research

Arbuscular mycorrhizal tree communities have greater soil fungal diversity and relative abundances of saprotrophs and pathogens compared to ectomycorrhizal tree communities
Appl Environ Microbiol. 2021 Oct 20:AEM0178221. doi: 10.1128/AEM.01782-21. Online ahead of print.ABSTRACTTrees associating with different mycorrhizas often differ in their effects on litter decomposition, nutrient cycling, soil organic matter (SOM) dynamics, and plant-soil interactions. For example, due to differences between arbuscular mycorrhizal (AM) and ectomycorrhizal (ECM) tree leaf and root traits, ECM-associated soil has slower rates of C and N cycling and lower N availability compared to AM-associated soil. These observations suggest many groups of non-mycorrhizal fungi should be affected by the mycorrhizal associ...
Source: Applied and Environmental Microbiology - October 20, 2021 Category: Microbiology Authors: Andrew C Eagar Ryan M Mushinski Amber L Horning Kurt A Smemo Richard P Phillips Christopher B Blackwood Source Type: research

Utilization efficiency of human milk oligosaccharides by human-associated < em > Akkermansia < /em > is strain-dependent
Appl Environ Microbiol. 2021 Oct 20:AEM0148721. doi: 10.1128/AEM.01487-21. Online ahead of print.ABSTRACTAkkermansia muciniphila are mucin degrading bacteria found in the human gut and are often associated with positive human health. However, despite being detected as early as one month of age, little is known about the role of Akkermansia in the infant gut. Human milk oligosaccharides (HMOs) are abundant components of human milk and are structurally similar to the oligosaccharides that comprise mucin, the preferred growth substrate of human-associated Akkermansia. A limited subset of intestinal bacteria has been shown to ...
Source: Applied and Environmental Microbiology - October 20, 2021 Category: Microbiology Authors: Estefani Luna Shanthi G Parkar Nina Kirmiz Stephanie Hartel Erik Hearn Marziiah Hossine Arinnae Kurdian Claudia Mendoza Katherine Orr Loren Padilla Katherine Ramirez Priscilla Salcedo Erik Serrano Biswa Choudhury Mousumi Paulchakrabarti Craig T Parker Ste Source Type: research

Two TonB-dependent transporters in < em > Methylosinus trichosporium < /em > OB3b are responsible for uptake of different forms of methanobactin and are involved in the canonical 'copper switch'
In this study, we demonstrate that different TonB-dependent transporters (TBDTs) in the model methanotroph Methylosinus trichosporium OB3b are responsible for uptake of either endogenous MB or exogenous MB. Interestingly, the presence of exogenous MB induces expression of its specific TBDT in M. trichosporium OB3b, suggesting that this methanotroph is able to actively take up MB produced by others. This work contributes to our understanding of how microbes collect and compete for copper, and also helps inform how such uptake coordinates the expression of different forms of methane monooxygenase. Such studies are likely to ...
Source: Applied and Environmental Microbiology - October 20, 2021 Category: Microbiology Authors: Peng Peng Christina S Kang-Yun Jin Chang Wenyu Gu Alan A DiSpirito Jeremy D Semrau Source Type: research

Isolation, identification, and characterization of lignocellulose-degrading < em > Geobacillus thermoleovorans < /em > from Yellowstone National Park
In this study, results obtain from G. thermolerovorans isolates originating from YNP springs are significant as very few microorganisms from alkaline thermal environments have been discovered to have lignin and cellulose biodegrading capabilities, and this work opens new avenues for the biotechnological valorization of lignocellulosic biomass at an industrial scale.PMID:34669438 | DOI:10.1128/AEM.00958-21 (Source: Applied and Environmental Microbiology)
Source: Applied and Environmental Microbiology - October 20, 2021 Category: Microbiology Authors: Margaux M Mesl é Rebecca C Mueller Jesse Peach Brian Eilers Brian P Tripet Brian Bothner Val érie Copié Brent M Peyton Source Type: research

< em > Streptomyces coelicolor < /em > vesicles: many molecules to be delivered
In conclusion, this analysis provides detailed information on S. coelicolor MVs under basal conditions and corresponding content, which may be useful in a next future to elucidate vesicle biogenesis and functions. Importance Streptomycetes are widely distributed in nature, and they are characterized by a complex life cycle that involves morphological differentiation. They are very relevant in industry because they produce about a half of the antibiotics used clinically and other important pharmaceutical products having natural origin. Streptomyces coelicolor is a model organism for the study of bacterial differentiation an...
Source: Applied and Environmental Microbiology - October 20, 2021 Category: Microbiology Authors: Teresa Faddetta Giovanni Renzone Alberto Vassallo Emilio Rimini Giorgio Nasillo Gianpiero Buscarino Simonpietro Agnello Mariano Licciardi Luigi Botta Andrea Scaloni Antonio Palumbo Piccionello Anna Maria Puglia Giuseppe Gallo Source Type: research

Competitive exclusion of phytopathogenic < em > Serratia marcescens < /em > from squash bug vectors by the gut endosymbiont < em > Caballeronia < /em >
Appl Environ Microbiol. 2021 Oct 20:AEM0155021. doi: 10.1128/AEM.01550-21. Online ahead of print.ABSTRACTMany insects harbor microbial symbiotic partners that offer protection against pathogens, parasitoids, and other natural enemies. Mounting evidence suggests that these symbiotic microbes can play key roles in determining infection outcomes in insect vectors, making them important players in the quest to develop novel vector control strategies. Using the squash bug Anasa tristis, we investigated how the presence of Caballeronia symbionts affected the persistence and intensity of phytopathogenic Serratia marcescens within...
Source: Applied and Environmental Microbiology - October 20, 2021 Category: Microbiology Authors: Sandra Y Mendiola Kayla S Stoy Susanne DiSalvo Cameron L Wynn David J Civitello Nicole M Gerardo Source Type: research

Cytochrome OmcS is not essential for extracellular electron transport via conductive pili in < em > Geobacter sulfurreducens < /em > strain KN400
Appl Environ Microbiol. 2021 Oct 20:AEM0162221. doi: 10.1128/AEM.01622-21. Online ahead of print.ABSTRACTThe multi-heme c-type cytochrome OmcS is one of the central components for extracellular electron transport in Geobacter sulfurreducens strain DL-1, but its role in other microbes, including other strains of G. sulfurreducens is currently a matter of debate. Therefore, we investigated the function of OmcS in G. sulfurreducens strain KN400, which is even more effective in extracellular electron transfer than strain DL-1. We found that deleting omcS from strain KN400 did not negatively impact the rate of Fe(III) oxide red...
Source: Applied and Environmental Microbiology - October 20, 2021 Category: Microbiology Authors: Xinying Liu Dawn E Holmes David J F Walker Yang Li David Meier Samantha Pinches Trevor L Woodard Jessica A Smith Source Type: research

Specialized Metabolite Mediated Predation Defense in the Marine Actinobacterium < em > Salinispora < /em >
Appl Environ Microbiol. 2021 Oct 20:AEM0117621. doi: 10.1128/AEM.01176-21. Online ahead of print.ABSTRACTThe obligate marine actinobacterial genus Salinispora has become a model organism for natural product discovery, yet little is known about the ecological functions of the compounds produced by this taxon. The aims of this study were to assess the effects of live cultures and culture extracts from two Salinispora species on invertebrate predators. In choice-based feeding experiments using the bacterivorous nematode Caenorhabditis elegans, live cultures of both Salinispora species were less preferred than E. coli. When gi...
Source: Applied and Environmental Microbiology - October 20, 2021 Category: Microbiology Authors: Robert N Tuttle Greg W Rouse Gabriel Castro-Falc ón Chambers C Hughes Paul R Jensen Source Type: research

Predation strategies of the bacterium < em > Bdellovibrio bacteriovorus < /em > result in overexploitation and bottlenecks
Appl Environ Microbiol. 2021 Oct 20:AEM0108221. doi: 10.1128/AEM.01082-21. Online ahead of print.ABSTRACTWith increasing antimicrobial resistance, alternatives for treating infections or removing resistant bacteria are urgently needed, such as the bacterial predator Bdellovibrio bacteriovorus or bacteriophage. Therefore, we need to better understand microbial predator-prey dynamics. We developed mass-action mathematical models of predation for chemostats, which capture the low substrate concentration and slow growth typical for intended application areas of the predators such as wastewater treatment, aquaculture or the gut...
Source: Applied and Environmental Microbiology - October 20, 2021 Category: Microbiology Authors: J Kimberley Summers Jan-Ulrich Kreft Source Type: research

Engineering a lysin with intrinsic antibacterial activity (LysMK34) with cecropin A enhances its antibacterial properties against < em > Acinetobacter baumannii < /em >
Appl Environ Microbiol. 2021 Oct 20:AEM0151521. doi: 10.1128/AEM.01515-21. Online ahead of print.ABSTRACTBacteriophage-encoded lysins are increasingly reported as alternatives to combat Acinetobacter baumannii infections for which limited therapeutic options are available. Some lysins such as LysMK34 have a C-terminal amphipathic helix allowing them to penetrate the otherwise impermeable outer membrane barrier. Another approach to kill Gram-negative pathogens with lysins relies on fusion of a peptide with outer membrane permeabilizing properties to the lysin. In this work, we aimed to leverage the intrinsic antibacterial a...
Source: Applied and Environmental Microbiology - October 20, 2021 Category: Microbiology Authors: Karim Abdelkader Diana Guti érrez H éctor Tamés-Caunedo Patricia Ruas-Madiedo Amal Safaan Ahmed S Khairalla Yasser Gaber Tarek Dishisha Yves Briers Source Type: research

Wildlife symbiotic bacteria are indicators of the health status of the host and its ecosystem
Appl Environ Microbiol. 2021 Oct 20:AEM0138521. doi: 10.1128/AEM.01385-21. Online ahead of print.ABSTRACTLactic acid bacteria (LAB) are gut symbionts that can be used as a model to understand the host-microbiota crosstalk under unpredictable environmental conditions such as wildlife ecosystems. The aim of this study was to determine whether viable LAB can be informative of the health status of wild boar populations. We monitored the genotype and phenotype of LAB based on markers that included safety and phylogenetic origin, antibacterial activity and immunomodulatory properties. A LAB profile dominated by lactobacilli appe...
Source: Applied and Environmental Microbiology - October 20, 2021 Category: Microbiology Authors: Maria Bravo Theo Combes Fernando Martinez-Estrada David Risco Pilar Gon çalves Waldo Garcia-Jimenez Rosario Cerrato Pedro Fernandez-Llario Jorge Gutierrez-Merino Source Type: research

Genome mosaicism in field strains of < em > Mycoplasma bovis < /em > as footprints of in-host horizontal chromosomal transfer
This study provides evidence that MCT can take place in the field, most likely during co-infections by multiple strains. Because mobile genetic elements (MGEs) are classical contributors of genome plasticity, the presence of phages, insertion sequences (ISs) and ICEs was also investigated. Data revealed that these elements are widespread within the M. bovis species and evidenced classical horizontal transfer of phages and ICEs in addition to MCT. These events contribute to wide-genome diversity and reorganization within this species and may have a tremendous impact on diagnostic and disease control. IMPORTANCE Mycoplasma b...
Source: Applied and Environmental Microbiology - October 20, 2021 Category: Microbiology Authors: Ana Garc ía-Galán Eric Baranowski Marie-Claude Hygonenq Mathilda Walch Guillaume Croville Christine Citti Christian De la Fe Laurent-Xavier Nouvel Source Type: research

Brussowvirus SW13 requires a cell surface-associated polysaccharide to recognise its < em > Streptococcus thermophilus < /em > host
Appl Environ Microbiol. 2021 Oct 20:AEM0172321. doi: 10.1128/AEM.01723-21. Online ahead of print.ABSTRACTFour bacteriophage insensitive mutants (BIMs) of the dairy starter bacterium Streptococcus thermophilus UCCSt50 were isolated following a challenge with the Brussowvirus SW13. The BIMs displayed an altered, sedimentation phenotype. Whole genome sequencing and comparative genomic analysis of the BIMs uncovered mutations within a family-2-glycosyltransferase-encoding gene (orf06955UCCSt50) located within the variable region of the cell wall-associated rhamnose-glucose polymer (Rgp) biosynthesis locus (designated here as t...
Source: Applied and Environmental Microbiology - October 20, 2021 Category: Microbiology Authors: Katherine Lavelle Irina Sadovskaya Evgeny Vinogradov Philip Kelleher Gabriele A Lugli Marco Ventura Douwe van Sinderen Jennifer Mahony Source Type: research

< em > Coprinopsis cinerea < /em > uses laccase Lcc9 as a defense strategy to eliminate oxidative stress during fungal-fungal interactions
Appl Environ Microbiol. 2021 Oct 20:AEM0176021. doi: 10.1128/AEM.01760-21. Online ahead of print.ABSTRACTFrequently, laccases are triggered during fungal cocultivation for overexpression. The function of these activated laccases during coculture has not been clarified. Previously, we reported that Gongronella sp. w5 (w5) (Mucoromycota, Mucoromycetes) specifically triggered the laccase Lcc9 overexpression in Coprinopsis cinerea (Basidiomycota, Agaricomycetes). To systematically analyze the function of the overexpressed laccase during fungal interaction, C. cinerea mycelia before and after the initial Lcc9 overexpression wer...
Source: Applied and Environmental Microbiology - October 20, 2021 Category: Microbiology Authors: Juanjuan Liu Can Peng Qiqi Han Mengyao Wang Gang Zhou Bin Ye Yazhong Xiao Zemin Fang Ursula K ües Source Type: research

Colibrimycins, novel halogenated hybrid PKS-NRPS compounds produced by < em > Streptomyces < /em > sp. CS147
Appl Environ Microbiol. 2021 Oct 20:AEM0183921. doi: 10.1128/AEM.01839-21. Online ahead of print.ABSTRACTThe improvement on genome sequencing techniques has brought to light the biosynthetic potential of actinomycetes due to the high number of gene clusters they present compared to the number of known compounds. Genome mining is a recent strategy in the search for novel bioactive compounds, which involves the analysis of sequenced genomes to identify uncharacterized natural product biosynthetic gene clusters, many of which are cryptic or silent under laboratory conditions, and to develop experimental approaches to identify...
Source: Applied and Environmental Microbiology - October 20, 2021 Category: Microbiology Authors: Laura Prado-Alonso Ignacio P érez-Victoria M ónica G Malmierca Ignacio Montero Elisa Rioja-Blanco Jes ús Martín Fernando Reyes Carmen M éndez Jos é A Salas Carlos Olano Source Type: research

Spt20, a structural subunit of the SAGA complex, regulates biofilm formation, asexual development, and virulence of < em > Aspergillus fumigatus < /em >
In this study, Spt20, an orthologue of the subunit of Saccharomyces cerevisiae transcriptional co-activator Spt-Ada-Gcn5-acetyltransferase (SAGA) complex, was identified as a regulator of biofilm formation and asexual development in A. fumigatus. The loss of spt20 caused severe defects in GAG biosynthesis, biofilm formation, conidiation, and virulence of A. fumigatus. RNA-sequence data demonstrated that Spt20 positively regulates the expression of GAG biosynthesis genes uge3 and agd3, developmental regulator medA, and genes involved in the conidiation pathway. Moreover, more than 10 subunits of the SAGA complex (known from...
Source: Applied and Environmental Microbiology - October 20, 2021 Category: Microbiology Authors: Yuan Chen James I P Stewart Shuai Liu Donald C Sheppard Ling Lu Shizhu Zhang Source Type: research

Arbuscular mycorrhizal tree communities have greater soil fungal diversity and relative abundances of saprotrophs and pathogens compared to ectomycorrhizal tree communities
Appl Environ Microbiol. 2021 Oct 20:AEM0178221. doi: 10.1128/AEM.01782-21. Online ahead of print.ABSTRACTTrees associating with different mycorrhizas often differ in their effects on litter decomposition, nutrient cycling, soil organic matter (SOM) dynamics, and plant-soil interactions. For example, due to differences between arbuscular mycorrhizal (AM) and ectomycorrhizal (ECM) tree leaf and root traits, ECM-associated soil has slower rates of C and N cycling and lower N availability compared to AM-associated soil. These observations suggest many groups of non-mycorrhizal fungi should be affected by the mycorrhizal associ...
Source: Applied and Environmental Microbiology - October 20, 2021 Category: Microbiology Authors: Andrew C Eagar Ryan M Mushinski Amber L Horning Kurt A Smemo Richard P Phillips Christopher B Blackwood Source Type: research

Utilization efficiency of human milk oligosaccharides by human-associated < em > Akkermansia < /em > is strain-dependent
Appl Environ Microbiol. 2021 Oct 20:AEM0148721. doi: 10.1128/AEM.01487-21. Online ahead of print.ABSTRACTAkkermansia muciniphila are mucin degrading bacteria found in the human gut and are often associated with positive human health. However, despite being detected as early as one month of age, little is known about the role of Akkermansia in the infant gut. Human milk oligosaccharides (HMOs) are abundant components of human milk and are structurally similar to the oligosaccharides that comprise mucin, the preferred growth substrate of human-associated Akkermansia. A limited subset of intestinal bacteria has been shown to ...
Source: Applied and Environmental Microbiology - October 20, 2021 Category: Microbiology Authors: Estefani Luna Shanthi G Parkar Nina Kirmiz Stephanie Hartel Erik Hearn Marziiah Hossine Arinnae Kurdian Claudia Mendoza Katherine Orr Loren Padilla Katherine Ramirez Priscilla Salcedo Erik Serrano Biswa Choudhury Mousumi Paulchakrabarti Craig T Parker Ste Source Type: research

Two TonB-dependent transporters in < em > Methylosinus trichosporium < /em > OB3b are responsible for uptake of different forms of methanobactin and are involved in the canonical 'copper switch'
In this study, we demonstrate that different TonB-dependent transporters (TBDTs) in the model methanotroph Methylosinus trichosporium OB3b are responsible for uptake of either endogenous MB or exogenous MB. Interestingly, the presence of exogenous MB induces expression of its specific TBDT in M. trichosporium OB3b, suggesting that this methanotroph is able to actively take up MB produced by others. This work contributes to our understanding of how microbes collect and compete for copper, and also helps inform how such uptake coordinates the expression of different forms of methane monooxygenase. Such studies are likely to ...
Source: Applied and Environmental Microbiology - October 20, 2021 Category: Microbiology Authors: Peng Peng Christina S Kang-Yun Jin Chang Wenyu Gu Alan A DiSpirito Jeremy D Semrau Source Type: research

Isolation, identification, and characterization of lignocellulose-degrading < em > Geobacillus thermoleovorans < /em > from Yellowstone National Park
In this study, results obtain from G. thermolerovorans isolates originating from YNP springs are significant as very few microorganisms from alkaline thermal environments have been discovered to have lignin and cellulose biodegrading capabilities, and this work opens new avenues for the biotechnological valorization of lignocellulosic biomass at an industrial scale.PMID:34669438 | DOI:10.1128/AEM.00958-21 (Source: Applied and Environmental Microbiology)
Source: Applied and Environmental Microbiology - October 20, 2021 Category: Microbiology Authors: Margaux M Mesl é Rebecca C Mueller Jesse Peach Brian Eilers Brian P Tripet Brian Bothner Val érie Copié Brent M Peyton Source Type: research

< em > Streptomyces coelicolor < /em > vesicles: many molecules to be delivered
In conclusion, this analysis provides detailed information on S. coelicolor MVs under basal conditions and corresponding content, which may be useful in a next future to elucidate vesicle biogenesis and functions. Importance Streptomycetes are widely distributed in nature, and they are characterized by a complex life cycle that involves morphological differentiation. They are very relevant in industry because they produce about a half of the antibiotics used clinically and other important pharmaceutical products having natural origin. Streptomyces coelicolor is a model organism for the study of bacterial differentiation an...
Source: Applied and Environmental Microbiology - October 20, 2021 Category: Microbiology Authors: Teresa Faddetta Giovanni Renzone Alberto Vassallo Emilio Rimini Giorgio Nasillo Gianpiero Buscarino Simonpietro Agnello Mariano Licciardi Luigi Botta Andrea Scaloni Antonio Palumbo Piccionello Anna Maria Puglia Giuseppe Gallo Source Type: research

Competitive exclusion of phytopathogenic < em > Serratia marcescens < /em > from squash bug vectors by the gut endosymbiont < em > Caballeronia < /em >
Appl Environ Microbiol. 2021 Oct 20:AEM0155021. doi: 10.1128/AEM.01550-21. Online ahead of print.ABSTRACTMany insects harbor microbial symbiotic partners that offer protection against pathogens, parasitoids, and other natural enemies. Mounting evidence suggests that these symbiotic microbes can play key roles in determining infection outcomes in insect vectors, making them important players in the quest to develop novel vector control strategies. Using the squash bug Anasa tristis, we investigated how the presence of Caballeronia symbionts affected the persistence and intensity of phytopathogenic Serratia marcescens within...
Source: Applied and Environmental Microbiology - October 20, 2021 Category: Microbiology Authors: Sandra Y Mendiola Kayla S Stoy Susanne DiSalvo Cameron L Wynn David J Civitello Nicole M Gerardo Source Type: research

Cytochrome OmcS is not essential for extracellular electron transport via conductive pili in < em > Geobacter sulfurreducens < /em > strain KN400
Appl Environ Microbiol. 2021 Oct 20:AEM0162221. doi: 10.1128/AEM.01622-21. Online ahead of print.ABSTRACTThe multi-heme c-type cytochrome OmcS is one of the central components for extracellular electron transport in Geobacter sulfurreducens strain DL-1, but its role in other microbes, including other strains of G. sulfurreducens is currently a matter of debate. Therefore, we investigated the function of OmcS in G. sulfurreducens strain KN400, which is even more effective in extracellular electron transfer than strain DL-1. We found that deleting omcS from strain KN400 did not negatively impact the rate of Fe(III) oxide red...
Source: Applied and Environmental Microbiology - October 20, 2021 Category: Microbiology Authors: Xinying Liu Dawn E Holmes David J F Walker Yang Li David Meier Samantha Pinches Trevor L Woodard Jessica A Smith Source Type: research

Specialized Metabolite Mediated Predation Defense in the Marine Actinobacterium < em > Salinispora < /em >
Appl Environ Microbiol. 2021 Oct 20:AEM0117621. doi: 10.1128/AEM.01176-21. Online ahead of print.ABSTRACTThe obligate marine actinobacterial genus Salinispora has become a model organism for natural product discovery, yet little is known about the ecological functions of the compounds produced by this taxon. The aims of this study were to assess the effects of live cultures and culture extracts from two Salinispora species on invertebrate predators. In choice-based feeding experiments using the bacterivorous nematode Caenorhabditis elegans, live cultures of both Salinispora species were less preferred than E. coli. When gi...
Source: Applied and Environmental Microbiology - October 20, 2021 Category: Microbiology Authors: Robert N Tuttle Greg W Rouse Gabriel Castro-Falc ón Chambers C Hughes Paul R Jensen Source Type: research

Predation strategies of the bacterium < em > Bdellovibrio bacteriovorus < /em > result in overexploitation and bottlenecks
Appl Environ Microbiol. 2021 Oct 20:AEM0108221. doi: 10.1128/AEM.01082-21. Online ahead of print.ABSTRACTWith increasing antimicrobial resistance, alternatives for treating infections or removing resistant bacteria are urgently needed, such as the bacterial predator Bdellovibrio bacteriovorus or bacteriophage. Therefore, we need to better understand microbial predator-prey dynamics. We developed mass-action mathematical models of predation for chemostats, which capture the low substrate concentration and slow growth typical for intended application areas of the predators such as wastewater treatment, aquaculture or the gut...
Source: Applied and Environmental Microbiology - October 20, 2021 Category: Microbiology Authors: J Kimberley Summers Jan-Ulrich Kreft Source Type: research

Engineering a lysin with intrinsic antibacterial activity (LysMK34) with cecropin A enhances its antibacterial properties against < em > Acinetobacter baumannii < /em >
Appl Environ Microbiol. 2021 Oct 20:AEM0151521. doi: 10.1128/AEM.01515-21. Online ahead of print.ABSTRACTBacteriophage-encoded lysins are increasingly reported as alternatives to combat Acinetobacter baumannii infections for which limited therapeutic options are available. Some lysins such as LysMK34 have a C-terminal amphipathic helix allowing them to penetrate the otherwise impermeable outer membrane barrier. Another approach to kill Gram-negative pathogens with lysins relies on fusion of a peptide with outer membrane permeabilizing properties to the lysin. In this work, we aimed to leverage the intrinsic antibacterial a...
Source: Applied and Environmental Microbiology - October 20, 2021 Category: Microbiology Authors: Karim Abdelkader Diana Guti érrez H éctor Tamés-Caunedo Patricia Ruas-Madiedo Amal Safaan Ahmed S Khairalla Yasser Gaber Tarek Dishisha Yves Briers Source Type: research

Wildlife symbiotic bacteria are indicators of the health status of the host and its ecosystem
Appl Environ Microbiol. 2021 Oct 20:AEM0138521. doi: 10.1128/AEM.01385-21. Online ahead of print.ABSTRACTLactic acid bacteria (LAB) are gut symbionts that can be used as a model to understand the host-microbiota crosstalk under unpredictable environmental conditions such as wildlife ecosystems. The aim of this study was to determine whether viable LAB can be informative of the health status of wild boar populations. We monitored the genotype and phenotype of LAB based on markers that included safety and phylogenetic origin, antibacterial activity and immunomodulatory properties. A LAB profile dominated by lactobacilli appe...
Source: Applied and Environmental Microbiology - October 20, 2021 Category: Microbiology Authors: Maria Bravo Theo Combes Fernando Martinez-Estrada David Risco Pilar Gon çalves Waldo Garcia-Jimenez Rosario Cerrato Pedro Fernandez-Llario Jorge Gutierrez-Merino Source Type: research

Articles of Significant Interest in This Issue
Appl Environ Microbiol. 2021 Oct 14;87(21):e0174721. doi: 10.1128/AEM.01747-21. Epub 2021 Oct 14.NO ABSTRACTPMID:34647818 | DOI:10.1128/AEM.01747-21 (Source: Applied and Environmental Microbiology)
Source: Applied and Environmental Microbiology - October 14, 2021 Category: Microbiology Source Type: research

Harnessing Escherichia coli for Bio-Based Production of Formate under Pressurized H < sub > 2 < /sub > and CO < sub > 2 < /sub > Gases
In this study, an E. coli host strain was engineered for the continuous production of formic acid from H2 and CO2 during bacterial growth in a pressurized batch bioreactor. Incorporation of tungsten, in place of molybdenum, in FHL-1 helped to impose a degree of catalytic bias on the enzyme. This work demonstrates that it is possible to couple cell growth to simultaneous, unidirectional formate production from carbon dioxide and develops a process for growth under pressurized gases. IMPORTANCE Greenhouse gas emissions, including waste carbon dioxide, are contributing to global climate change. A basket of solutions is needed...
Source: Applied and Environmental Microbiology - October 14, 2021 Category: Microbiology Authors: Magali Roger Thomas C P Reed Frank Sargent Source Type: research