Details

Autor(en) / Beteiligte

• Jiang, Daqing
• Zeng, Quan
• Banerjee, Biswarup
• Lin, Haiping
• Srok, John
• Yu, Manda
• Yang, Ching‐Hong

Titel

The phytopathogen Dickeya dadantii 3937 cpxR locus gene participates in the regulation of virulence and the global c‐di‐GMP network

Ist Teil von

• Molecular plant pathology, 2022-08, Vol.23 (8), p.1187-1199

Ort / Verlag

Oxford: John Wiley & Sons, Inc

Erscheinungsjahr

2022

Link zum Volltext

Quelle

Electronic Journals Library

Beschreibungen/Notizen

• Bacteria use signal transduction systems to sense and respond to their external environment. The two‐component system CpxA/CpxR senses misfolded envelope protein stress and responds by up‐regulating envelope protein factors and down‐regulating virulence factors in several animal pathogens. Dickeya dadantii is a phytopathogen equipped with a type III secretion system (T3SS) for manipulating the host immune response. We found that deletion of cpxR enhanced the expression of the T3SS marker gene hrpA in a designated T3SS‐inducing minimal medium (MM). In the ∆cpxR mutant, multiple T3SS and c‐di‐GMP regulators were also up‐regulated. Subsequent analysis revealed that deletion of the phosphodiesterase gene egcpB in ∆cpxR abolished the enhanced T3SS expression. This suggested that CpxR suppresses EGcpB levels, causing low T3SS expression in MM. Furthermore, we found that the ∆cpxR mutant displayed low c‐di‐GMP phenotypes in biofilm formation and swimming. Increased production of cellular c‐di‐GMP by in trans expression of the diguanylate cyclase gene gcpA was negated in the ∆cpxR mutant. Here, we propose that CpxA/CpxR regulates T3SS expression by manipulating the c‐di‐GMP network, in turn modifying the multiple physiological activities involved in the response to environmental stresses in D. dadantii. The stress response regulator CpxR modulates T3SS expression and multiple physiological activities by manipulating the c‐di‐GMP network in the phytopathogen Dickeya dadantii.