Premium
Gene organization of the ornithine decarboxylase‐encoding region in Morganella morganii
Author(s) -
De Las Rivas B.,
Marcobal A.,
Muñoz R.
Publication year - 2007
Publication title -
journal of applied microbiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.889
H-Index - 156
eISSN - 1365-2672
pISSN - 1364-5072
DOI - 10.1111/j.1365-2672.2006.03188.x
Subject(s) - morganella morganii , ornithine decarboxylase antizyme , biology , ornithine decarboxylase , putrescine , genetics , escherichia coli , biochemistry , gene , microbiology and biotechnology , enterobacteriaceae , enzyme
Aims: The production of putrescine is a relevant property related to food quality and safety. Morganella morganii is responsible for putrescine production in fresh fish decomposition. The aim of this study was to gain deeper insights into the genetic determinants for putrescine production in M. morganii . Methods and Results: The 6972 bp DNA region showed the presence of three complete and two partial open reading frames all transcribed in the same direction. The second and third genes putatively coded for an ornithine decarboxylase (SpeF) and a putrescine–ornithine antiporter (PotE), respectively, and constituted an operon. The speF gene has been expressed in Escherichia coli HT414, an ornithine decarboxylase defective mutant, resulting in ornithine decarboxylase activity. The genetic organization of the SpeF–PotE‐encoding region in M. morganii is different to that of E. coli and several Salmonella species. Conclusions: The speF gene cloned from M. morganii encodes a functional ornithine decarboxylase involved in putrescine production. Phylogenetic tree based on 16S rDNA showed that ornithine decarboxylase activity is not related to a specific phylogenetic tree branch in Enterobacteriaceae. Significance and Impact of the Study: The identification of the DNA region involved in putrescine production in M. morganii will allow additional research on their induction and regulation in order to minimize putrescine production in foods.