Different outer membrane c‐type cytochromes are involved in direct interspecies electron transfer to Geobacter or Methanosarcina species  

作　　者：Dawn E.Holmes Jinjie Zhou Jessica A.Smith Caiqin Wang Xinying Liu Derek R.Lovley 

机构地区：[1]Department of Microbiology,University of Massachusetts‐Amherst,Amherst,Massachusetts,USA [2]Department of Physical and Biological Science,Western New England University,Springfield,Massachusetts,USA [3]Institute for Advanced Study,Shenzhen University,Shenzhen,China [4]Department of Biomolecular Sciences,Central Connecticut State University,New Britain,Connecticut,USA [5]College of Environment,Zhejiang University of Technology,Hangzhou,China [6]College of Environmental Science and Engineering,Beijing Forestry University,Beijing,China.

出　　处：《mLife》2022年第3期272-286,共15页微生物（英文）

基　　金：This study was supported by the Army Research Office and was accomplished under grant number W911NF‐17‐1‐0345.

摘　　要：Direct interspecies electron transfer(DIET)may be most important in methanogenic environments,but mechanistic studies of DIET to date have primarily focused on cocultures in which fumarate was the terminal electron acceptor.To better understand DIET with methanogens,the transcriptome of Geobacter metallireducens during DIET‐based growth with G.sulfurreducens reducing fumarate was compared with G.metallireducens grown in coculture with diverse Methanosarcina.The transcriptome of G.metallireducens cocultured with G.sulfurreducens was significantly different from those with Methanosarcina.Furthermore,the transcriptome of G.metallireducens grown with Methanosarcina barkeri,which lacks outer‐surface c‐type cytochromes,differed from those of G.metallireducens cocultured with M.acetivorans or M.subterranea,which have an outer‐surface c‐type cytochrome that serves as an electrical connect for DIET.Differences in G.metallireducens expression patterns for genes involved in extracellular electron transfer were particularly notable.Cocultures with c‐type cytochrome deletion mutant strains,ΔGmet_0930,ΔGmet_0557 andΔGmet_2896,never became established with G.sulfurreducens but adapted to grow with all three Methanosarcina.Two porin–cytochrome complexes,PccF and PccG,were important for DIET;however,PccG was more important for growth with Methanosarcina.Unlike cocultures with G.sulfurreducens and M.acetivorans,electrically conductive pili were not needed for growth with M.barkeri.Shewanella oneidensis,another electroactive microbe with abundant outer‐surface c‐type cytochromes,did not grow via DIET.The results demonstrate that the presence of outer‐surface c‐type cytochromes does not necessarily confer the capacity for DIET and emphasize the impact of the electron‐accepting partner on the physiology of the electron‐donating DIET partner.

关 键 词：c‐type cytochrome direct interspecies electron transfer(DIET) extracellular electron transfer GEOBACTER METHANOSARCINA 

分 类 号：O64[理学—物理化学]