The Fe2+ chelator Proferrorosamine A: a gene cluster of Erwinia rhapontici P45 involved in its synthesis and its impact on growth of Erwinia amylovora CFBP1430

; ; ; ; ; (). The Fe2+ chelator Proferrorosamine A: a gene cluster of Erwinia rhapontici P45 involved in its synthesis and its impact on growth of Erwinia amylovora CFBP1430. Microbiology Peer reviewed.

Proferrorosamine A (proFRA) is an iron (Fe2+) chelator produced by the opportunistic plant pathogen Erwinia rhapontici P45. To identify genes involved in proFRA synthesis a transposon mutagenesis was performed. The identified 9.3 kb gene cluster, comprising seven genes, designated rosA to rosG, encodes for proteins that are involved in proFRA synthesis. Based on gene homologies, a biosynthetic pathway model for proFRA is proposed.To obtain a better understanding of the effect of proFRA on non-proFRA producing bacteria, E. rhapontici P45 was co-cultured with Erwinia amylovora CFBP1430, a fire blight causing plant pathogen. E. rhapontici P45 but not corresponding proFRA negative mutants led to a pink coloration of E. amylovora CFBP1430 colonies on King's B (KB) agar, indicating accumulation of the proFRA-iron complex ferrorosamine, and growth inhibition in vitro. By saturating proFRA containing extracts with Fe2+ the inhibitory effect was neutralized, suggesting that the iron chelating capability of proFRA is responsible for the growth inhibition of E. amylovora CFBP1430.