ROLE OF SELECTED EXTRACELLULAR FUNCTION SIGMA FACTORS IN CARBOHYDRASE GENE EXPRESSION IN SACCHAROPHAGUS DEGRADANS 2-40

Abstract

This project explores the role of selected ECF sigma factors in regulating carbohydrase gene expression in Saccharophagus degradans 2-40. ECF sigma factors most likely to be involved in carbohydrase regulation were identified by scoring for the presence of high sequence similarity in cellulolytic but not in non-cellulolytic bacterial species. Cellvibrio japonicus, Teredinibacter turnerae, and Hahella chejuensis were determined to be the cellulolytic species most appropriate for evaluating transcriptional regulators for a role in carbohydrase regulation. Two sigma factors were identified in this survey. These sigma factor genes were cloned into a plasmid vector and expressed in S. degradans. Cellulase activity was detected for cell lysates of glucose-grown cultures of a strain expressing the sigma factor corresponding to gene 2407. It was concluded that sigma factor 2407 is involved in the regulation of endoglucanases in the S. degradans cellulolytic system.