To separate one base metal mineral from another by flotation, it is indispensable to identify chemical reagents that specifically interact with the surface metal sites of one mineral or a group of minerals. This work studies the interactions of chelating collectors which offer the best potential for collecting abilities and mineral specificity with a typical refractory oxide mineral (malachite)...

Stenotrophomonas maltophilia is an emerging nosocomial pathogen. Despite the broad spectrum of syndromes associated with S. maltophilia infections, little is known about its virulence factors, including siderophore production. The aims of this work were to detect S. maltophilia siderophores and to determine their chemical nature. We studied 31 S. maltophilia isolates from device-associated infe...

Siderophores are a diverse group of low molecular weight biogenic metallophores with a particular affinity for Fe(III) but they also have potential to complex a number of other polyvalent metal cations, including Cr(III). Here we show that two hydroxamate siderophores, desferrioxamine B and rhodotorulic acid, at environmentally relevant concentrations, facilitate the dissolution of hydroxy-Cr(I...

Covalent attachment of cognate amino acid to the cognate tRNA is a prerequisite for the faithful synthesis of proteins in the cell. Aminoacylation of tRNA, catalyzed by aminoacyl-tRNA synthetases (aaRSs), proceeds by a two-step reaction whereby amino acid is first activated and then transferred to the 3'-ribose of tRNA. Serine hydroxamate (SerHX) is an interesting analogue of serine as it exhib...

An enzyme, cytidine monophosphate sialic acid synthetase, was purified from hog submaxillary glands. This enzyme (or enzymes) catalyzes the synthesis of CMP-N-acetylneuraminic acid or CMP-N-glycolylneuraminic acid or both and inorganic pyrophosphate from CTP and the corresponding sialic acids. The preparation was inactive with other known sialic acids and analogues of these compounds, and was a...

Growth of Legionella species in a defined medium deficient in iron did not result in the production of phenolic or hydroxamate siderophores which could be detected by chemical or biological assay methods. Growth of a variety of other gram-negative organisms under the same conditions resulted in the production of both hydroxamate and phenolate siderophores. The iron-deficient medium limited grow...

The objective of this work was to study the production of siderophores by endophytic bacteria Methylobacterium spp., which occupy the same ecological niche as Xylella fastidiosa subsp. pauca (Xfp) in citrus plants. The siderophore production of Methylobacterium strains was tested according to chromeazurol agar assay test (CAS), Csáky test (hydroxamate-type) and Arnow test (catechol-type). In ad...

Hydroxamic acids chelate metals with high affinity and form hydrolytically stable complexes with metal oxides such as TiO2. However, these appealing binding properties can cause problems during the preparation and application of metallocatalysts with appended hydroxamate anchoring groups. Here we show that the tetrahydropyran (THP) O-protected hydroxamate group can be cleaved in situ on a TiO2 ...