Novel aerobic and thermophilic bacteria from temperate zone marine habitats

Abstract

Diverse microorganisms are reported from marine environment, displaying various physico-chemical ecosystems which are three dimensional, however, many of which still not identified. Amongst, solar saltern, tidal flat, and near shore sediments are one of the rich sources of novel microorganisms. Thermophilic bacteria was enriched with 0.1% of lignin or cellulose at 50 degree Celsius and then spread on marine agar 2216. The 74 isolates affiliated with Bacillales (65%), Proteobacteria (16%), Actinobacteria (8%), Bacteroidetes (7%), and Archaea (4%) and approx. 20% of isolates constitutes novel taxon. Some of the isolates closely related with previously reported thermophiles such as Aeribacillus palidus, Bacillus alveayuensis, B. sporothermodurans, Geobacillus spp., Halorubrum chaoviator etc. but some has been not known as thermophilic or thermotolerants. Amongst, four isolates produces deep branch in each phylogenetic group shows highest similarity with Caldalkalibacillus uzonensis (MEBiC 09487, 89%), Mechercharimyces asporophorigenens (MEBiC 07976, 91%), Pararhodobacter aggregans (MEBiC 09520, 90.7%), or Rhodothermus profundi (MEBiC 09517, 88%). The four isolates were neutrophilic and slightly halophilic and showed 50 degree Celsius as optimum growth temperature. The results implied that novel deep branched microorganisms could be enriched by combination of high temperature and recalcitrant substratests are one of the rich sources of novel microorganisms. Thermophilic bacteria was enriched with 0.1% of lignin or cellulose at 50 degree Celsius and then spread on marine agar 2216. The 74 isolates affiliated with Bacillales (65%), Proteobacteria (16%), Actinobacteria (8%), Bacteroidetes (7%), and Archaea (4%) and approx. 20% of isolates constitutes novel taxon. Some of the isolates closely related with previously reported thermophiles such as Aeribacillus palidus, Bacillus alveayuensis, B. sporothermodurans, Geobacillus spp., Halorubrum chaoviator etc. but some has been not known as thermophilic or thermotolerants. Amongst, four isolates produces deep branch in each phylogenetic group shows highest similarity with Caldalkalibacillus uzonensis (MEBiC 09487, 89%), Mechercharimyces asporophorigenens (MEBiC 07976, 91%), Pararhodobacter aggregans (MEBiC 09520, 90.7%), or Rhodothermus profundi (MEBiC 09517, 88%). The four isolates were neutrophilic and slightly halophilic and showed 50 degree Celsius as optimum growth temperature. The results implied that novel deep branched microorganisms could be enriched by combination of high temperature and recalcitrant substrates