Metal-binding characteristics of the gamma-glutamyl capsular polymer of Bacillus licheniformis ATCC 9945

Journal Article · Sat Dec 01 00:00:00 EST 1990 · Applied and Environmental Microbiology; (USA)

OSTI ID:5957820

McLean, R J.C.; Beauchemin, D; Clapham, L; Beveridge, T J ^[1]

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1. Queen's Univ., Kingston, Ontario (Canada) Univ. of Guelph, Ontario (Canada)

The metal-binding affinity of the anionic poly-{gamma}-D-glutamyl capsule of Bacillus licheniformis was investigated by using Na{sup +}, Mg{sup 2+}, Al{sup 3+}, Ca{sup 2+}, Cr{sup 3+}, Mn{sup 2+}, Fe{sup 3+}, Ni{sup 2+}, and Cu{sup 2+}. Exposure of purified capsule to excess concentrations of Na{sup +} revealed it to contain 8.2 {mu}mol of anionic sites per mg on the basis of Na binding. Other metal ions were then added in ionic concentrations equivalent to 25, 50, 75, 100, 200, and 400% of the available anionic sites. The binding characteristics varied with the metal being investigated. Addition of Cu{sup 2+}, Al{sup 3+}, Cr{sup 3+}, or Fe{sup 3+} induced flocculation. These metal ions showed the greatest affinity for B. licheniformis capsule in competitive-binding experiments. Flocculation was not seen with the addition of other metal ions. With the exception of Ni{sup 2+} and Fe{sup 3+} all capsule-metal-binding sites readily saturated. Ni{sup 2+} had low affinity for the polymer, and its binding was increased at high metal concentrations. Fe{sup 3+} binding resulted in the development of rust-colored ferrihydrite which itself could bind additional metal.

• OSTI ID: 5957820
• Journal Information: Applied and Environmental Microbiology; (USA), Vol. 56:12; ISSN 0099-2240
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
BACILLUS LICHENIFORMIS
PHYSIOLOGY
METALS
SORPTION
ABSORPTION SPECTROSCOPY
ALUMINIUM COMPOUNDS
CALCIUM COMPOUNDS
CATIONS
CHROMIUM COMPOUNDS
COPPER COMPOUNDS
IRON COMPOUNDS
MAGNESIUM COMPOUNDS
MANGANESE COMPOUNDS
NICKEL COMPOUNDS
SODIUM COMPOUNDS
ALKALI METAL COMPOUNDS
ALKALINE EARTH METAL COMPOUNDS
BACILLUS
BACTERIA
CHARGED PARTICLES
ELEMENTS
IONS
MICROORGANISMS
SPECTROSCOPY
TRANSITION ELEMENT COMPOUNDS
551000* - Physiological Systems