title: Sphere of influence of indole acetic acid and nitric oxide in bacteria.
abstract: Bacterial biosynthesis of the phytohormone, indole-3-acetic acid (IAA) is well established and along with the diffusible gaseous molecule, nitric oxide (NO) is known to positively regulate the developmental processes of plant roots. IAA and NO act as signaling molecules in plant-microbe interactions as they modulate the gene expression in both, plants and microorganisms. Although IAA and NO may not be required for essential bacterial physiological processes, numerous studies point towards a crosstalk between IAA and NO in the rhizosphere. In this review, we describe various IAA and NO-responsive or sensing genes/proteins/regulators. There is also growing evidence for the interaction of IAA and NO with other plant growth regulators and the involvement of NO with the quorum sensing system in biofilm formation and virulence. This interactive network can greatly impact the host plant-microbe interactions in the soil. Coupled with this, the specialized σ(54) -dependent transcription observed in some of the IAA and NO-influenced genes can confer inducibility to these traits in bacteria and may allow the expression of IAA and NO-influenced microbial genes in nutrient limiting or changing environmental conditions for the benefit of plants.
authors.affiliation: TERI Deakin Nanobiotechnology Centre, Biotechnology and Bioresources Division, The Energy and Resources Institute, Darbari Seth Block, India Habitat Centre, Lodhi Road, New Delhi, India.
authors.forename: Vatsala
authors.initials: V
authors.lastname: Koul
authors.forename: Alok
authors.initials: A
authors.lastname: Adholeya
authors.forename: Mandira
authors.initials: M
authors.lastname: Kochar
mesh_terms: D001419:Bacteria / Q000187:drug effects / Q000378:metabolism*; D015964:Gene Expression Regulation, Bacterial / Q000187:drug effects; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D053263:Gene Regulatory Networks / Q000187:drug effects; D007210:Indoleacetic Acids / Q000378:metabolism*; D009569:Nitric Oxide / Q000378:metabolism*; D010937:Plant Growth Regulators / Q000378:metabolism*; D010944:Plants / Q000187:drug effects
chemical_list: D007210:Indoleacetic Acids; D010937:Plant Growth Regulators; D009569:Nitric Oxide; C030737:indoleacetic acid
keywords: Indole acetic acid; Nitric oxide; Plant growth promoting bacteria