Isolation and characterization of methane utilizing bacteria from wetland paddy ecosystem

Abstract

Methylotrophic bacteria which are known to utilize C1 compounds including methane. Research during past few decades increased the interest in finding out novel genera of methane degrading bacteria to efficiently utilize methane to decrease global warming effect. Moreover, evaluation of certain known plant growth promoting strains for their methane degrading potential may open up a new direction for multiple utility of such cultures. In this study, efficient methylotrophic cultures were isolated from wetland paddy fields of Gujarat. From the overall morphological, biochemical and molecular characterization studies, the isolates were identified and designated as Bacillus aerius AAU M 8; Rhizobium sp. AAU M 10; B. subtilis AAU M 14; Paenibacillus illinoisensis AAU M 17 and B. megaterium AAU M 29. Gene specific PCR analysis of the isolates, P. illinoisensis, B. aerius, Rhizobium sp. and B. subtilis showed presence of pmoA gene encoding α subunit particulate methane monooxygenase cluster. B. megaterium, P. illinoisensis, Rhizobium sp. and Methylobacterium extrorquens showed presence of mmoX gene encoding α subunit of the hydroxylase component of the soluble methane monooxygenase cluster. P. illinoisensis and Rhizobium sp. showed presence mxaF gene encoding α subunit region of methanol dehydrogenase gene cluster showing that both isolates are efficient utilizers of methane. To the best of our knowledge, this is the first time report showing presence of methane degradation enzymes and genes within the known PGPB group of organisms from wet land paddy agro-ecosystem, which is considered as one of the leading methane producer.

Endophytic occupation of legume root nodules by nifH-positive non-rhizobial bacteria, and their efficacy in the groundnut (Arachis hypogaea)

“…In addition, seven isolates were grown in Luria broth for 24 h, and genomic DNA was extracted using the cetyltrimethylammonium bromide (CTAB) method (Sambrook et al 1989;Jhala et al 2014). The integrity and concentration of the purified DNA was determined by agarose gel electrophoresis.…”

Genomic, biochemical, and phylogenetic evaluation of bacteria isolated from deep-sea sediment harboring methane hydrates

“…From rich-media cultures we obtained 40 isolates of Bacillales, including the genus Bacillus, Brevibacillus and Paenibacillus, all with known marine diversity (Ettoumi et al 2013;Lee et al 2013;Jhala et al 2014;Zheng et al 2014). These isolates were obtained from site PC44, located within a pockmark with thriving benthic fauna, including Acharax sp.…”

Prokaryotic Community Profile in a Wetland Ecosystem

“…Gammaproteobacteria is represented by Methylobacterium sp. Wetlands are one of the significant sources of single carbon (C 1 ) compounds like methane, methanol, halomethanes, methylated sulphur compounds, etc (Hanson and Hanson, 1996;Jhala et al, 2014). Several species of Methylobacterium are reported to be facultative methylotrophs involved in the degradation of C 1 compounds such as methane, methanol and help significantly in reducing C 1 compound emission from wetlands (Balachandar et al, 2008).…”