Abstract

A promoter-protein fusion library was constructed and analyzed previously which covered about 8% promoter-proximal genes from Escherichia coli in respect to their reading frames, protein productivity as well as expressional regulations under normal and various environmental stress conditions (Talukder et al., 1994, Bioscience Biochemistry and Biotechnology, 58:117-120). In this study, we further analyzed 13 significantly responsive genes. β-galactosidase expression levels were varied among the examined clones, indicating that the library having different ranges of promoters from stronger to weaker. DNA database analysis revealed that out of 13 genes studied here, 11 and 2 genes were found to known and unknown or new genes, respectively. Moreover, new findings in case of three genes having interesting structural organizations were recorded this time. The present study supports all previous data to conclude that about 5 - 10% E. coli genes are co-regulated under the control of complex regulatory circuits.

Key words: Gene expression, RNA-polymerase, gene organization.