Comparative genomic analysis of two-component regulatory proteins in <it>Pseudomonas syringae</it>

• Main Authors: Ussery David W, Resano Ohiana, Kiil Kristoffer, Lavín José L, Oguiza José A
• Format: Article
• Language: English
• Published: BMC 2007-10-01
• Series: BMC Genomics
• Online Access: http://www.biomedcentral.com/1471-2164/8/397

<p>Abstract</p> <p>Background</p> <p><it>Pseudomonas syringae </it>is a widespread bacterial plant pathogen, and strains of <it>P. syringae </it>may be assigned to different pathovars based on host specificity among different plant species. The genomes of <it>P. syringae </it>pv. <it>syringae </it>(<it>Psy</it>) B728a, pv. <it>tomato </it>(<it>Pto</it>) DC3000 and pv. <it>phaseolicola </it>(<it>Pph</it>) 1448A have been recently sequenced providing a major resource for comparative genomic analysis. A mechanism commonly found in bacteria for signal transduction is the two-component system (TCS), which typically consists of a sensor histidine kinase (HK) and a response regulator (RR). <it>P. syringae </it>requires a complex array of TCS proteins to cope with diverse plant hosts, host responses, and environmental conditions.</p> <p>Results</p> <p>Based on the genomic data, pattern searches with Hidden Markov Model (HMM) profiles have been used to identify putative HKs and RRs. The genomes of <it>Psy </it>B728a, <it>Pto </it>DC3000 and <it>Pph </it>1448A were found to contain a large number of genes encoding TCS proteins, and a core of complete TCS proteins were shared between these genomes: 30 putative TCS clusters, 11 orphan HKs, 33 orphan RRs, and 16 hybrid HKs. A close analysis of the distribution of genes encoding TCS proteins revealed important differences in TCS proteins among the three <it>P. syringae </it>pathovars.</p> <p>Conclusion</p> <p>In this article we present a thorough analysis of the identification and distribution of TCS proteins among the sequenced genomes of <it>P. syringae</it>. We have identified differences in TCS proteins among the three <it>P. syringae </it>pathovars that may contribute to their diverse host ranges and association with plant hosts. The identification and analysis of the repertoire of TCS proteins in the genomes of <it>P. syringae </it>pathovars constitute a basis for future functional genomic studies of the signal transduction pathways in this important bacterial phytopathogen.</p>