ABSTRACT: Draft genome of Syntrophomonas zehnderi – an obligate syntrophic bacterium degrading long chain fatty acids in co-culture with Methanobacterium formicicum
Project description:Syntrophomonas wolfei is an anaerobic syntrophic microbe that degrades short-chain fatty acids to acetate, hydrogen, and/or formate. This thermodynamically unfavorable process proceeds through a series of reactive acyl-Coenzyme A species (RACS). In other prokaryotic and eukaryotic systems, the production of intrinsically reactive metabolites correlates with acyl-lysine modifications, which have been shown to play a significant role in metabolic processes. Analogous studies with syntrophic bacteria, however, are relatively unexplored and we hypothesize that highly abundant acylations could exist in S. wolfei proteins, corresponding to the RACS derived from degrading fatty acids. Here, by mass spectrometry-based proteomics (LC-MS/MS), we characterize and compare acylome profiles of two S. wolfei subspecies grown on different carbon substrates. Because modified S. wolfei proteins are sufficiently abundant for post-translational modification (PTM) analyses without antibody enrichment, we could identify types of acylations comprehensively, observing six types (acetyl-, butyryl-, 3-hydroxybutyryl-, crotonyl-, valeryl-, hexanyl-lysine), two of which have not been reported in any system previously. All of the acyl-PTMs identified correspond directly to RACS in fatty acid degradation pathways. A total of 369 sites of modification were identified on 237 proteins. Changing the carbon substrate altered the acylation profile. Moreover, structural studies and in vitro acylation assays of a heavily modified enzyme, acetyl-CoA transferase, provided insight on the possible impact of these acyl-protein modifications. Our findings link protein acylation by RACS to shifts in cellular metabolism.
Project description:The syntrophic growth of strain 195 with Desulfovibrio vulgaris Hildenborough (DVH) and/or Methanobacterium congolense (MC) enhanced TCE dechlorination process by faster dechlorination rate and more robust growth. Transcriptomes of strain 195 grown in isolation, co- and tri-cultures were obtained by microarray experiments to find out the differential expressed genes corresponding to the syntrophic growth. Thus we can better understand the role of DVH and MC within this syntrophy.
Project description:Syntrophomonas wolfei is an anaerobic syntrophic microbe that degrades short-chain fatty acids to acetate, hydrogen, and/or formate. This thermodynamically unfavorable process proceeds through a series of reactive acyl-Coenzyme A species (RACS). In other prokaryotic and eukaryotic systems, the production of intrinsically reactive metabolites correlates with acyl-lysine modifications, which have been shown to play a significant role in metabolic processes. Analogous studies with syntrophic bacteria, however, are relatively unexplored and we hypothesize that highly abundant acylations could exist in S. wolfei proteins, corresponding to the RACS derived from degrading fatty acids. Here, by mass spectrometry-based proteomics (LC-MS/MS), we characterize and compare acylome profiles of two S. wolfei subspecies grown on different carbon substrates. Because modified S. wolfei proteins are sufficiently abundant to analyze post-translational modifications (PTMs) without antibody enrichment, we could identify types of acylations comprehensively, observing six types (acetyl-, butyryl-, 3-hydroxybutyryl-, crotonyl-, valeryl-, and hexanyl-lysine), two of which have not been reported in any system previously. All of the acyl-PTMs identified correspond directly to RACS in fatty acid degradation pathways. A total of 369 sites of modification were identified on 237 proteins. Structural studies and in vitro acylation assays of a heavily modified enzyme, acetyl-CoA transferase, provided insight on the potential impact of these acyl-protein modifications. The extensive changes in acylation-type, abundance, and modification sites with carbon substrate suggest that protein acylation by RACS may be an important regulator of syntrophy.
Project description:A combination of shotgun metaproteomics and 16S rRNA gene pyrosequencing wasused to identify potential functional pathways and key microorganisms involved in long-chain fatty acids (LCFA) anaerobic conversion. Microbial communities degrading saturated- and unsaturated-LCFA were compared. Archaeal communities were mainly composed of Methanosaeta, Methanobacterium and Methanospirillum species, both in stearate (saturated C18:0) and oleate (mono-unsaturated C18:1) incubations. Over 80% of the 16S rRNA gene sequences clustered within the Methanosaeta genus, which is in agreement with the high number of proteins assigned to this group (94%). Archaeal proteins related with methane metabolism were highly expressed. Bacterial communities were rather diverse and the composition dissimilar between incubations with saturated- and unsaturated-LCFA. Stearate-degrading communities were enriched in Deltaproteobacteria (34% of the assigned sequences), while microorganisms clustering within the Synergistia class were more predominant in oleate incubation (25% of the assigned sequences). Bacterial communities were diverse and active, given by the high percentage of proteins related with mechanisms of energy production. Several proteins were assigned to syntrophic bacteria, emphasizing the importance of the interactions between acetogens and methanogens in energy exchange and formation in anaerobic LCFA-rich environments.
Project description:A combination of shotgun metaproteomics and 16S rRNA gene pyrosequencing wasused to identify potential functional pathways and key microorganisms involved in long-chain fatty acids (LCFA) anaerobic conversion. Microbial communities degrading saturated- and unsaturated-LCFA were compared. Archaeal communities were mainly composed of Methanosaeta, Methanobacterium and Methanospirillum species, both in stearate (saturated C18:0) and oleate (mono-unsaturated C18:1) incubations. Over 80% of the 16S rRNA gene sequences clustered within the Methanosaeta genus, which is in agreement with the high number of proteins assigned to this group (94%). Archaeal proteins related with methane metabolism were highly expressed. Bacterial communities were rather diverse and the composition dissimilar between incubations with saturated- and unsaturated-LCFA. Stearate-degrading communities were enriched in Deltaproteobacteria (34% of the assigned sequences), while microorganisms clustering within the Synergistia class were more predominant in oleate incubation (25% of the assigned sequences). Bacterial communities were diverse and active, given by the high percentage of proteins related with mechanisms of energy production. Several proteins were assigned to syntrophic bacteria, emphasizing the importance of the interactions between acetogens and methanogens in energy exchange and formation in anaerobic LCFA-rich environments.
Project description:A combination of shotgun metaproteomics and 16S rRNA gene pyrosequencing wasused to identify potential functional pathways and key microorganisms involved in long-chain fatty acids (LCFA) anaerobic conversion. Microbial communities degrading saturated- and unsaturated-LCFA were compared. Archaeal communities were mainly composed of Methanosaeta, Methanobacterium and Methanospirillum species, both in stearate (saturated C18:0) and oleate (mono-unsaturated C18:1) incubations. Over 80% of the 16S rRNA gene sequences clustered within the Methanosaeta genus, which is in agreement with the high number of proteins assigned to this group (94%). Archaeal proteins related with methane metabolism were highly expressed. Bacterial communities were rather diverse and the composition dissimilar between incubations with saturated- and unsaturated-LCFA. Stearate-degrading communities were enriched in Deltaproteobacteria (34% of the assigned sequences), while microorganisms clustering within the Synergistia class were more predominant in oleate incubation (25% of the assigned sequences). Bacterial communities were diverse and active, given by the high percentage of proteins related with mechanisms of energy production. Several proteins were assigned to syntrophic bacteria, emphasizing the importance of the interactions between acetogens and methanogens in energy exchange and formation in anaerobic LCFA-rich environments.
Project description:A combination of shotgun metaproteomics and 16S rRNA gene pyrosequencing wasused to identify potential functional pathways and key microorganisms involved in long-chain fatty acids (LCFA) anaerobic conversion. Microbial communities degrading saturated- and unsaturated-LCFA were compared. Archaeal communities were mainly composed of Methanosaeta, Methanobacterium and Methanospirillum species, both in stearate (saturated C18:0) and oleate (mono-unsaturated C18:1) incubations. Over 80% of the 16S rRNA gene sequences clustered within the Methanosaeta genus, which is in agreement with the high number of proteins assigned to this group (94%). Archaeal proteins related with methane metabolism were highly expressed. Bacterial communities were rather diverse and the composition dissimilar between incubations with saturated- and unsaturated-LCFA. Stearate-degrading communities were enriched in Deltaproteobacteria (34% of the assigned sequences), while microorganisms clustering within the Synergistia class were more predominant in oleate incubation (25% of the assigned sequences). Bacterial communities were diverse and active, given by the high percentage of proteins related with mechanisms of energy production. Several proteins were assigned to syntrophic bacteria, emphasizing the importance of the interactions between acetogens and methanogens in energy exchange and formation in anaerobic LCFA-rich environments.