Anaerolineaceae and Methanosaeta turned to be the dominant microorganisms in alkanes-dependent methanogenic culture after long-term of incubation

TY - JOUR

T1 - Anaerolineaceae and Methanosaeta turned to be the dominant microorganisms in alkanes-dependent methanogenic culture after long-term of incubation

AU - Liang, Bo

AU - Wang, Li Ying

AU - Mbadinga, Serge Maurice

AU - Liu, Jin Feng

AU - Yang, Shi Zhong

AU - Gu, Ji Dong

AU - Mu, Bo Zhong

N1 - Publisher Copyright: © 2015, Liang et al.

PY - 2015/12/19

Y1 - 2015/12/19

N2 - The methanogenic alkanes-degrading enrichment culture which had been incubated for over 1,300 days amended with n-alkanes (C15–C20) was investigated through clone libraries of bacteria, archaea and assA, mcrA functional genes. These enrichment cultures were obtained from oily sludge after an initial incubation of the oily sludge without any carbon source and then an enrichment transfer with n-alkanes (C15–C20) for acclimation. Activation of alkanes, methane precursor generation and methanogenic pathways are considered as three pivotal stages for the continuous methanogenesis from degradation of alkanes. The presence of functional genes encoding the alkylsuccinate synthase α-subunit indicated that fumarate addition is most likely the one of initial activation step for degradation of n-alkanes. Degradation intermediates of n-alkanes were octadecanoate, hexadecanoate, butyrate, isobutyrate, acetate and propionate, which could provide the appropriate substrates for acetate formation. Both methyl coenzyme M reductase gene and 16S rRNA gene analysis showed that microorganisms of Methanoseata were the most dominant methanogens, capable of using acetate as the electron donor to produce methane. Bacterial clone libraries showed organisms of Anaerolineaceae (within the phylum of Chloroflexi) were predominant (45.5%), indicating syntrophically cooperation with Methanosaeta archaea was likely involved in the process of methanogenic degradation of alkanes. Alkanes may initially be activated via fumarate addition and degraded to fatty acids, then converted to acetate, which was further converted to methane and carbon dioxide by methanogens.

AB - The methanogenic alkanes-degrading enrichment culture which had been incubated for over 1,300 days amended with n-alkanes (C15–C20) was investigated through clone libraries of bacteria, archaea and assA, mcrA functional genes. These enrichment cultures were obtained from oily sludge after an initial incubation of the oily sludge without any carbon source and then an enrichment transfer with n-alkanes (C15–C20) for acclimation. Activation of alkanes, methane precursor generation and methanogenic pathways are considered as three pivotal stages for the continuous methanogenesis from degradation of alkanes. The presence of functional genes encoding the alkylsuccinate synthase α-subunit indicated that fumarate addition is most likely the one of initial activation step for degradation of n-alkanes. Degradation intermediates of n-alkanes were octadecanoate, hexadecanoate, butyrate, isobutyrate, acetate and propionate, which could provide the appropriate substrates for acetate formation. Both methyl coenzyme M reductase gene and 16S rRNA gene analysis showed that microorganisms of Methanoseata were the most dominant methanogens, capable of using acetate as the electron donor to produce methane. Bacterial clone libraries showed organisms of Anaerolineaceae (within the phylum of Chloroflexi) were predominant (45.5%), indicating syntrophically cooperation with Methanosaeta archaea was likely involved in the process of methanogenic degradation of alkanes. Alkanes may initially be activated via fumarate addition and degraded to fatty acids, then converted to acetate, which was further converted to methane and carbon dioxide by methanogens.

KW - 16S rRNA gene

KW - Alkanes degradation

KW - Anaerolineaceae

KW - Methanogenesis

KW - Methanosaeta

KW - Microbial community

UR - http://www.scopus.com/inward/record.url?scp=84934898262&partnerID=8YFLogxK

U2 - 10.1186/s13568-015-0117-4

DO - 10.1186/s13568-015-0117-4

M3 - 文章

AN - SCOPUS:84934898262

SN - 2191-0855

VL - 5

JO - AMB Express

JF - AMB Express

IS - 1

M1 - 37

ER -