Siderophore: Structural And Functional Characterisation – A Comprehensive Review

Abstract

Plants and microbes have enormous importance in our daily life. Iron is said to be the fourth most abundant element in the earth's crust from soil, still many plants face problem in uptaking iron because it is found in insoluble form, which severely restricts the bioavailability of this metal. In response to this, microorganisms present in soil such as Pseudomonas sp., Enterobacter genera, Bacillus and Rhodococcus produce special iron carriers or iron-binding compounds called as ‘siderphores’ or ‘siderochromes’. This paper is an attempt to review the importance of siderphores in enhancing plants’ iron utilisation strategies, the mode of transport of siderophores along with iron across the memberane and depending on the difference in their chemical structure, functional moiety and their source of isolation of four different types of siderophore (hydroxamates, catecholates, carboxylates and siderophore with mixed ligand). Siderophore and their derivative have large application in agriculture as to increase soil fertility and as biocontrol for fungal pathogen. This review unlike other reviews includes (1) types of siderophore, (2) the structural difference amongst them, (3) siderophore biosynthesis, (4) transport mechanism, (5) the genetics of siderophore and (6) their efficacy in human life.

Pseudomonas mediated nutritional and growth promotional activities for sustainable food security

“…The Pseudomonas aeruginosa strain GRC1 produces hydroxamate siderophores, pyoverdine in an iron-deficit environment ( Sah and Singh, 2015 ). The spectral enhancement of siderophores improves the rhizospheric competence of Pseudomonas sp.…”

Promising bacterial genera for agricultural practices: An insight on plant growth-promoting properties and microbial safety aspects

“…Siderophores are produced by microorganisms, such as bacteria and fungi, as well as by some graminaceous plants, as part of a strategy to obtain iron from the environment (Sah and Singh, 2015). As discussed above (iron deficiency in plants: chlorosis; Section 2.1.2), Fe(III) is very bio unavailable; in physiological conditions, the dissolved iron levels can be as low as 10 −10 mol•L −1 (Kraemer, 2004).…”

Phylogenetical coherence of Pseudomonas in unexplored soils of Himalayan region

“…Others include mineral solubilization (e.g., phosphorus), competition, and induced systemic resistance (Adesemoye et al 2008 ). Siderophore produced by fluorescent Pseudomonas rapidly colonizes the roots and significantly increases the plant growth by 144 % in field tests (Kloepper et al 1980 ; Sah and Singh 2015 ). In this study, 56 strains were siderophore producers, and these strains could be efficiently utilized for the plant growth promotion as siderophores mobilize insoluble iron from soil and increase biological availability for plants.…”