CLONING, NUCLEOTIDE-SEQUENCE, AND FUNCTIONAL EXPRESSION OF THE ESCHERICHIA-COLI ENOLASE (ENO) GENE IN A TEMPERATURE-SENSITIVE ENO MUTANT STRAIN

The entire Escherichia coli eno gene was cloned by functional compleme ntation of a newly isolated temperature-sensitive enolase mutant and i ts nucleotide sequence determined. The deduced amino acid sequence is homologous to other known prokaryotic or eukaryotic enolases and amino acid residues, assumed to be involved in substrate or cofactor bindin g and catalysis, were found to be strictly conserved among all enolase proteins. Expression of the eno gene under the control of the lac pro moter/operator resulted in an IPTG-inducible production of enzymatical ly active enolase in wild-type and enolase mutant strains.