Kinetic analysis of bacteriophage Sf6 binding to outer membrane protein a using whole virions.

Kinetic analysis of bacteriophage Sf6 binding to outer membrane protein a using whole virions. Acta Virol. 2019;63(4):450-458 Authors: Hubbs NB, Whisby-Pitts MM, McMurry JL Abstract For successful infection, viruses must recognize their respective host cells. A common mechanism of host recognition by viruses is to utilize a portion of the host cell as a receptor. Bacteriophage Sf6, which infects Shigella flexneri, uses lipopolysaccharide as a primary receptor and then requires interaction with a secondary receptor, a role that can be fulfilled by either outer membrane proteins (Omp) A or C. Our previous work showed that specific residues in the loops of OmpA mediate Sf6 infection. To better understand Sf6 interactions with OmpA loop variants, we determined the kinetics of these interactions through the use of biolayer interferometry, an optical biosensing technique that yields data similar to surface plasmon resonance. Here, we successfully tethered whole Sf6 virions, determined the binding constant of Sf6 to OmpA to be 36 nM. Additionally, we showed that Sf6 bound to five variant OmpAs and the resulting kinetic parameters varied only slightly. Based on these data, we propose a model in which Sf6: Omp receptor recognition is not solely based on kinetics, but likely also on the ability of an Omp to induce a conformational change that results in productive infection. Keywords: Sf6; Shigella flexneri; OmpA; biolayer interferometry. PMID: 31802688 [PubM...
Source: Acta Virologica - Category: Infectious Diseases Authors: Tags: Acta Virol Source Type: research

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Source: ClinicalTrials.gov - Category: Research Source Type: clinical trials
Authors: Habenstein B, El Mammeri N, Tolchard J, Lamon G, Tawani A, Berbon M, Loquet A Abstract Among the Gram-negative bacterial secretion systems, type III secretion systems (T3SS) possess a unique extracellular molecular apparatus called the needle. This macromolecular protein assembly is a nanometre-size filament formed by the helical arrangement of hundreds of copies of a single, small protein, which is highly conserved between T3SSs from animal to plant bacterial pathogens. The needle filament forms a hollow tube with a channel ~20 Å in diameter that serves as a conduit for proteins secreted...
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Source: Process Biochemistry - Category: Biochemistry Source Type: research
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Source: The Lancet Global Health - Category: International Medicine & Public Health Source Type: research
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Source: Medscape Hiv-Aids Headlines - Category: Infectious Diseases Tags: Infectious Diseases Journal Article Source Type: news
In conclusion, our study provides evidence that BBR regulates fecal metabolites to ameliorate 5-Fu induced intestinal mucositis by modifying gut microbiota.Graphical abstract
Source: Biomedicine and Pharmacotherapy - Category: Drugs & Pharmacology Source Type: research
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Source: Materials Chemistry and Physics - Category: Materials Science Source Type: research
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Source: International Journal of Microbiology - Category: Microbiology Tags: Int J Microbiol Source Type: research
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