Pseudomonas mendocina Siderophores

From Pseudomonas mendocina five siderophores were isolated by chromatography. They are reported to have identical molecular masses of 1,152 Da (the also reported 3a) value of 929 Da is an error L. E. Hersman, private communication) and an identical amino acid composition, which has not been revealed 141a). Color reactions show the presence of a hydroxamate, but not of a catecholate grouping. A gene analysis suggests a partial sequence acyl-Asp-Dab-Ser-formylOHOm-Ser-formylOHOm where asparagine could be OHAsp and the C-terminal ornithine cOHOm 9b). In which way the five isomeric siderophores with identical molecular masses differ from each other is not clear. 

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Structural work may take its time. Examples are Pseudomonas mendocina (Sect. 2.9) where the first structural data were reported in 2000 and the next pertinent publication appeared in 2008, or Legionella pneumophila (Sect. 4.5) whose legiobactin was first characterized in 2000, further details followed in 2007 and 2009, with loose ends in both cases. Only partially characterized siderophores are mentioned wherever data were available in order to stimulate further work. This would be worthwhile siderophore research is a fascinating branch of natural products chemistry promising sometimes surprising results e.g. 311, 388)). 

Hersman LE, Huang A, Maurice PA, Forsythe JH (2000) Siderophore Production and Iron Reduction by Pseudomonas mendocina in Response to Iron Deprivation. Geomicrobiology J 17 261... 

Hersman L. E., Huang A., Maurice P. A., and Forsythe J. H. (2000) Siderophore production and iron reduction by pseudomonas mendocina in response to iron deprivation. Geomicrobiol. J. 17, 261-273. 

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