Open AccessCharacterization of the cellulolytic complex (cellulosome) of Clostridium acetobutylicum
Author(s) -
Sabathé Fabrice,
Bélaı¨ch Anne,
Soucaille Philippe
Publication year - 2002
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/j.1574-6968.2002.tb11450.x
Subject(s) - cellulosome , clostridium acetobutylicum , biology , gene cluster , biochemistry , clostridium , microbiology and biotechnology , gene , cellulase , chemistry , bacteria , genetics , clostridium thermocellum , enzyme , butanol , ethanol
A large cellulosomal gene cluster was identified in the recently sequenced genome of Clostridium acetobutylicum ATCC 824. Sequence analysis revealed that this cluster contains the genes for the scaffolding protein CipA, the processive endocellulase Cel48A, several endoglucanases of families 5 and 9, the mannanase Man5G, and a hydrophobic protein, OrfXp. Surprisingly, genetic organization of this large cluster is very similar to that of Clostridium cellulolyticum , the model of mesophilic clostridial cellulosomes. As C. acetobutylicum is unable to grow on cellulosic substrates, the existence of a cellulosomal gene cluster in the genome raises questions about its expression, function and evolution. Biochemical evidence for the expression of a cellulosomal protein complex was investigated. The results of sodium dodecyl sulfate–polyacrylamide gel electrophoresis, N‐terminal sequencing and Western blotting with antibodies against specific components of the C. cellulolyticum cellulosome suggest that at least four major cellulosomal proteins are present. In addition, despite the fact that no cellulolytic activities were detected, we report here the evidence for the production of a high molecular mass cellulosomal complex in C. acetobutylicum .