Cloning, sequence analysis, and expression of ansB from Pseudomonas fluorescens, encoding periplasmic glutaminase/asparaginase

A gene (ansB) encoding a class II glutaminase/asparaginase has been cloned From Pseudomonas fluorescens and characterized by DNA sequencing, promoter analysis and heterologous expression in Escherichia coli. We show that ansB is monocistronic and depends on the alternate sigma factor sigma(54) for e xpression. A second open reading Frame located downstream of ansB is highly homologous to a number of bacterial genes that encode secreted endonucleas es of unknown function. (C) 1999 Federation of European Microbiological Soc ieties.