摘要 |
<p>This invention provides novel microorganisms which have a nonfunctional tryptophan repressor (trpR) protein. The preferred microorganisms, E. coli strains, LMS-73, LMS-117, and LMS-118, display enhanced levels of protein expression when transformed with suitable expression vectors. Also described is a plasmid, pRAL1, which when transformed into a suitable host, preferably LMS-117 or LMS-118, results in enhanced levels of protein expression. Also described is a method of increasing protein expression by inactivating repressor control of the tryptophan operon.</p> |