Chemical inhibition of acid production by acidophilic thiobacilli was tested using a variety of metals and chelators (alone and in combination) including Hg(II), Ag(I), Co(II), Mo(VI), Cu(II), Zn(II), Cd(II), EDTA and NTA. When tested individually, Hg(II) and Ag(I) showed toxic effects at concentrations of 10-5 M and below; Cd(II), Zn(II) and NTA were noninhibitory at millimolar concentrations. Combination experiments showed both synergistic and antagonistic effects on chemical toxicities. Antagonism was apparent in experiments involving Cu(II)-EDTA, Cu(II)-Fe(III) and Cu(II)-Co(II). Synergism was apparent in experiments involving simultaneous addition of Mo(VI), Cu(II), Co(II) and Zn(II). In general, inhibitors either completely blocked or delayed the onset of acid production. In those cases where delayed reactions were observed, acid production began following an acclimation period on the order of days to weeks. Acclimation and metals speciation experiments suggest that adaptation events are due to biologically dependent changes in inhibitor speciation.
| Identifer | oai:union.ndltd.org:arizona.edu/oai:arizona.openrepository.com:10150/277061 |
| Date | January 1989 |
| Creators | Milner, Larry Fred, 1959- |
| Contributors | Arnold, Robert G. |
| Publisher | The University of Arizona. |
| Source Sets | University of Arizona |
| Language | en_US |
| Detected Language | English |
| Type | text, Thesis-Reproduction (electronic) |
| Rights | Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author. |
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