Phenotypic characterization of thermophilic, anaerobic, cellulolytic-xylanolytic bacterium Herbivorax saccincola by comparative genome analysis

Publication date: Available online 1 February 2020Source: Enzyme and Microbial TechnologyAuthor(s): Shimpei Aikawa, Phakhinee Thianheng, Sirilak Baramee, Umbhorn Ungkulpasvich, Chakrit Tachaapaikoon, Rattiya Waeonukul, Patthra Pason, Khanok Ratanakhanokchai, Akihiko KosugiAbstractThe genome sequences of thermophilic, anaerobic, and cellulolytic-xylanolytic bacterium Herbivorax saccincola strains A7 and GGR1 have recently been determined. Although both strains belong to the same species, A7 is alkaliphilic, non-endospore-forming, and ammonium-assimilating, whereas GGR1 is neutrophilic, endospore-forming, and non-ammonium-assimilating. To better understand the phenotypic diversity among H. saccincola strains, the genome sequences of A7 and GGR1 were compared. A7 contained three additional genes showing similarity to an alkaline stress-associated ABC-transporter but lacked four endospore formation-associated genes, AUG58543 and AUG58618 (encoding SpoVT), AUG57258 (encoding SpoVS), and AUG58614 (encoding YdhD), all of which were present in GGR1. In addition, A7 contained key ammonia assimilation genes PPQ67145 and PQQ66619, encoding ornithine cyclodeaminase and arginase, respectively, which were absent in GGR1. There was no difference in the number and types of cellulosomal-scaffolding proteins and glycosyl hydrolases between the two strains. However, cellulase and xylanase enzymes from A7 demonstrated greater activity and stability at an alkaline pH compared with those from GG...
Source: Enzyme and Microbial Technology - Category: Biotechnology Source Type: research