ABSTRACT
A novel Gram-stain-positive, rod-shaped, motile and endospore-forming novel bacterial strain 25nlg(T) was isolated from Lonar soda lake, in India. Based on the 16S rRNA gene sequence analysis, it was identified as a member of Firmicutes, being most closely related to Bacillus patagoniensis PAT 05(T) (96.6 %) and other members in the genus Bacillus (<96.0 %). Strain 25nlg(T) was catalase and oxidase-positive. The strain grows optimally at a pH of 9.5 with 4-6 % (w/v) NaCl and temperature of 35-37 °C. The cell wall of the strain 25nlg(T) contains meso-diaminopimelic acid as the diagnostic amino acid. Polar lipids include diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, an unknown phospholipid (PL2), an aminophospholipid (APL2) and three unknown lipids (L2-4). The predominant isoprenoid quinone was MK-7. iso-C15:0 (41.7 %) was the predominant fatty acid, and significant proportions of anteiso-C15:0 (20.8 %), C12:0 (5.5 %), anteiso-C17:0 (4.9 %), iso-C17:0 (4.5 %) were also detected in the strain 25nlg(T). The DNA G+C content of the strain 25nlg(T) was 40.5 mol%. The results of molecular, physiological and biochemical tests allowed a clear phenotypic differentiation of strain 25nlg(T) from all other members of the genus Bacillus. Strain 25nlg(T) represents a novel member of the genus Bacillus, for which the name Bacillus lonarensis sp. nov. is proposed. The type strain is 25nlg(T) (=KCTC 33413(T) = LMG 27974(T) = CGMCC = 1.12817(T)).
Subject(s)
Bacillus/classification , Bacillus/isolation & purification , Lakes/microbiology , Bacillus/cytology , Bacillus/physiology , Base Composition , Cell Wall/chemistry , DNA, Bacterial/genetics , Diaminopimelic Acid/analysis , Fatty Acids/analysis , Genes, rRNA , Hydrogen-Ion Concentration , India , Molecular Sequence Data , Nucleic Acid Hybridization , Phospholipids/analysis , Phylogeny , RNA, Ribosomal, 16S/genetics , Sequence Analysis, DNA , Sodium Chloride/analysis , Spores, Bacterial/physiology , TemperatureABSTRACT
The present study reports two bacteria, designated 87I and 112A, which were isolated from soil and activated sludge samples from Hyderabad, India, and that are capable of producing poly-3-hydroxybutyrate (PHB). Based on phenotypical features and genotypic investigations, these microorganisms were identified as Bacillus spp. Their optimal growth occurred between 28 degrees C and 30 degrees C and pH 7. Bacillus sp. 87I yielded a maximum of 70.04% dry cell weight (DCW) PHB in medium containing glucose as carbon source, followed by 55.5% DCW PHB in lactose-containing medium, whereas Bacillus sp. 112A produced a maximum of 67.73% PHB from glucose, 58.5% PHB from sucrose, followed by 50.5% PHB from starch as carbon substrates. The viscosity average molecular mass (M (v)) of the polymers from Bacillus sp. 87I was 513 kDa and from Bacillus sp. 112A was 521 kDa. All the properties of the biopolymers produced by the two strains 87I and 112A were characterized.
