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7.8 Biological Functions of Siderophore
Siderophore affects the plant and microbes in several significant ways. These are
discussed in detail as follows.
7.8.1 An Iron-Scavenging Compound
Siderophores have the ability to support the growth factor in all fungi and auxotrophic organism despite the fact that they are producing or non-producing species.
Several auxotrophic organisms found to be in underdeveloped stage in the absence
of these compounds require siderophores for their growth. For instance, Pilobolus
kleinii utilizes coprogen as an essential growth factor (Dave and Dube 2000). The
siderophore-mediated transport system facilitates and enhances the efficient competency among microbes for the consumption of available iron to make survival of one
type of microbe over the other. This is advantageous in case of non-pathogenic species producing more siderophores as it competes more efficiently for iron and limiting the growth of pathogenic species (less competent) of the same organism at the
same time (e.g. Fusarium species, Aspergillus ochraceus) (Aznar et al. 2014).
7.8.2 Virulence Factor
The siderophore-mediated transport system also plays an important role in microbial pathogenicity. Host pathogenic microorganism acquires iron to survive, and
restricting its availability to others is considered to be an effective defence mechanism of host microbes that suggest that siderophores can act as virulence factors.
For example, Microbotryum violaceum siderophore (mutant of plant pathogen)
accumulates less rhodotorulic acid as compared to its wild type that exhibits minimal pathogenicity. On the other hand, mutant of Ustilago maydis (plant pathogen)
showed defectiveness in siderophore production and is found to be as virulent as its
wild-type strains. In addition, phototoxic and immunosuppressive effects also contribute to virulence in pathogenic organism in terms of chelating activity in siderophores. For example, Alternaria cassiae produces siderophore such as coprogen
and ferricrocin which act as phytotoxins and several other siderophores such as
desferrichrome which exhibits immunosuppressive effect in mouse model (Ecker
et al. 2018).
7 Contrasting Role of Fungal Siderophore in Metal Ion Complex Formation
7.8 Biological Functions of Siderophore
Siderophore affects the plant and microbes in several significant ways. These are
discussed in detail as follows.
7.8.1 An Iron-Scavenging Compound
Siderophores have the ability to support the growth factor in all fungi and auxotrophic organism despite the fact that they are producing or non-producing species.
Several auxotrophic organisms found to be in underdeveloped stage in the absence
of these compounds require siderophores for their growth. For instance, Pilobolus
kleinii utilizes coprogen as an essential growth factor (Dave and Dube 2000). The
siderophore-mediated transport system facilitates and enhances the efficient competency among microbes for the consumption of available iron to make survival of one
type of microbe over the other. This is advantageous in case of non-pathogenic species producing more siderophores as it competes more efficiently for iron and limiting the growth of pathogenic species (less competent) of the same organism at the
same time (e.g. Fusarium species, Aspergillus ochraceus) (Aznar et al. 2014).
7.8.2 Virulence Factor
The siderophore-mediated transport system also plays an important role in microbial pathogenicity. Host pathogenic microorganism acquires iron to survive, and
restricting its availability to others is considered to be an effective defence mechanism of host microbes that suggest that siderophores can act as virulence factors.
For example, Microbotryum violaceum siderophore (mutant of plant pathogen)
accumulates less rhodotorulic acid as compared to its wild type that exhibits minimal pathogenicity. On the other hand, mutant of Ustilago maydis (plant pathogen)
showed defectiveness in siderophore production and is found to be as virulent as its
wild-type strains. In addition, phototoxic and immunosuppressive effects also contribute to virulence in pathogenic organism in terms of chelating activity in siderophores. For example, Alternaria cassiae produces siderophore such as coprogen
and ferricrocin which act as phytotoxins and several other siderophores such as
desferrichrome which exhibits immunosuppressive effect in mouse model (Ecker
et al. 2018).
7 Contrasting Role of Fungal Siderophore in Metal Ion Complex Formation