title: Spectroscopic characterization of mineral crystals produced by the bacterium Azospirillum brasilense.
abstract: The results of spectroscopic structural and trace elemental analyses of mineral crystals produced by the soil nitrogen-fixing bacterium Azospirillum brasilense cultivated in a synthetic medium are presented and discussed. The mineral formed is shown to have a structure close to struvite (MgNH(4)PO(4) x 6H(2)O; ASTM file No. 15-762) with some differences which may be attributed to the presence of isomorphic admixtures of other cations (struvite is known to have a variety of forms). AAS/AES and ion chromatography analyses for a number of biologically important microelements and their role in the formation of the crystal structure, as well as some questions related to biomineralization are also discussed.
authors.affiliation: Laboratory of Structural Research Methods, Institute of Biochemistry and Physiology of Plants and Microorganisms, Russian Academy of Sciences, 410015, Saratov, Russia.
authors.forename: A A
authors.initials: AA
authors.lastname: Kamnev
authors.forename: L P
authors.initials: LP
authors.lastname: Antonyuk
authors.forename: A V
authors.initials: AV
authors.lastname: Chernyshev
authors.forename: V V
authors.initials: VV
authors.lastname: Ignatov
authors.forename: M C
authors.initials: MC
authors.lastname: De Vargas