Abstract

Serratia marcescens (GBB151) was isolated and genetically modified for high-yielding pigment production capacity that could be employed for industrial purposes. Ethidium bromide-induced mutagenesis of GBB151 resulted in the generation of eight mutant isolates (GBB151Ea - GBB151Eh). The chemical mutants of S. marcescens obtained produced 5-fold more pigment than the wild-type organism. The wild-type GBB151 produced 413.9 unit/cell, while the mutant strains produced pigments with yields ranging from 841.7 to 2008.5 unit/cell. RAPD-PCR analysis showed different amplicons patterns of native as well as mutant derivatives. The factorial analysis diagram and the dendrogram showed a degree of dissimilarity among the wild-type bacterial isolate GBB151 and its mutants. Mutant strains GBB151Ec and GBB151Ef were closest to the wild-type as they appeared in the same quadrant. GBB151Ed which had lost its ability to produce pigment was farthest and in the different quadrant to the wild-type. These study provided insight into improvement in pigment production by manipulating genetic make-up of S. marcencens, thus meeting industrial demand.

Key words: Pigment; RAPD-PCR; mutagenesis; Serratia Marcescens; ethidium bromide