Discovery of a novel gene involved in autolysis of Clostridium cells

Cell a utolysis plays important physiological roles in the life cycle of clostridial cells.Unders tanding the genetic ba-sis of the autolysis phenomenon of pathogenic Clostridi-um or solvent producing Clostridium cells might provide new insights into this important species.Genes that might be involved in autolysis of Clostridium acetobutylicum,a model clostridial species,were investigated in this study.Twelve putative autolysin genes were predicted in C.ace-tobutylicum DSM 1731 genome through bioinformatics analysis.Of these 12 genes,gene SMB_G3117 was select-ed for testing the in tracellular autolysin activity,growth profi le,viable cell numbers,and cellular morphology.We found that overexpression of SMB_G3117 gene led to earlier ceased growth,signifi cantly increased number of dead cells,and clear electrolucent cavities,while disrup-tion of SMB_G3117 gene exhibited remarkably reduced intracellular autolysin activity.These results indicate that SMB_G3117 is a novel gene involved in cellular autolysis of C.acetobutylicum.