Thanks, but you have to tell us more about the reason for adding the prefix "acidi". Now, who makes these decisions ? Journal editors, book authors, and convinced researchers.
While discussing microorganisms, their action on sulfide minerals needs also some clarification. This is now chemistry and not terminology. I will quote a letter that appeared in Minerals Engineering 15, 307-308 (2002) which needs comments from readers:
How do bacteria interact with minerals? This is the title of the most recent paper published on this subject in which its author concludes by the following statement, “This is a compelling evidence that the only role of bacteria is the oxidation of ferrous ions and sulfur” . This subject has been debated over the past forty years . One argument is that the bacteria possess a specific biological mechanism to degrade the mineral and thereby gain energy directly from the sulfide mineral. The other argument is that ferric ions in solution that dissolve the mineral and the bacteria gain their energy requirements from regenerating the ferric ions. An extensive literature on bacterial leaching exists as can be attested from the monographs devoted to this subject [3, 4] and the many conferences held that resulted in voluminous proceedings [5-23].
It seems, however, that there is agreement that the rate of dissolution of sulfide minerals by bacterial action is approximately proportional to the solubility product of the sulfide concerned as expressed recently by Tributsch  a view that had been already expressed by Torma and his co-workers many years ago . If this is the case, then it can be conceived that the metabolic products of the microorganisms will homogenously catalyze the oxidation of the sulfide ion generated when the mineral is slurried in water:
MS(s) → M2+(aq) + S2-(aq) K= [M2+] [S2-]
S2-(aq) + 2O2(aq) → SO42-(aq)
where M is divalent metal and K is the solubility product. The above equilibrium will then shift to the right as more sulfide ion is oxidized thus more mineral will go into solution.
It is evident that the nearer the microorganism is to the sulfide surface the more effective will be the action of the metabolic products on the S2- ions, provided that oxygen is available in abundance . Naturally, the metabolic products will also catalyze the oxidation of Fe2+ ions and any elemental sulfur that may form as a result of the action of Fe3+ ions on the sulfide .
In summary, there is no transfer of electrons, the breaking of bonds in the mineral is due to the forces of hydration, and the process is the addition of oxygen atoms to the lone pairs of electrons on the hydrated sulfide ion, a reaction that is catalyzed by bacterial metabolic products.
1) F.K. Crundwell, “How Do Bacteria Interact With Minerals?”, pp. 149-157 in International Biohydrometallurgy Symposium, volume 1, edited by V.S.T. Ciminelli and O. Garcia Jr., Elsevier, Amsterdam 2001
2) W. Sand, T. Gehrke, P.-G. Joza, and A. Schippers, “Direct versus Indirect Bioleaching”, pp. 27-49 in Biohydrometallurgy and the Environment, volume 1, edited by R. Amils and A. Ballester, Elsevier, Amsterdam 1999
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5) W. Schwartz, editor, Conference Bacterial Leaching,Verlag Chemie, Weinheim, Germany 1977
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7) L.E. Murr, A.E. Torma, and J.A. Brierley, editors, Metallurgical Applications of Bacterial Leaching and Related Microbiological Phenomena, Academic Press, New York 1978
8) Anonymous, Proceedings of the International Conference on Use of Microorganisms in Hydrometallurgy, Hungarian Academy of Sciences, Pécs 1980
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10) J.A. Clum and L.A. Haas, editors, Microbiological Effects on Metallurgical Proceses, The Metallurgical Society-AIME, Warrendale, PA 1986
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19) T. Vargas et al., editors, Biohydrometallurgical Processing, 2 volumes, University of Chile, Santiago 1995
20) Anonymous, Proceedings of the International Biohydrometallurgy Symposium (Biomine ’97), Australian Mineral Foundation, Glenside, S. Australia 1997
21) V.S.T. Ciminelli and O. Garcia Jr., editors, International Biohydrometallurgy Symposium, 2 volumes, Elsevier, Amsterdam 2001
22) R. Amils and A. Ballester, editors, Biohydrometallurgy and the Environment, 2 volumes, Elsevier, Amsterdam 1999
23) S.K. Kawatra and K.A. Natarajan, editors, Mineral Biotechnology: Microbial Aspects of Mineral Benefication, Metal Extraction, and Environment Control, Society for Mining, Metallurgy and Exploration, Littleton, Colorado 2001
24) H. Tributsch, “Direct versus Indirect Bioleaching”, pp. 51-60 in Biohydrometallurgy and the Environment, volume 1, edited by R. Amils and A. Ballester, Elsevier, Amsterdam 1999
25) A.E. Torma et al., “Kinetics of Bio-Oxidation of Metal Sulfides”, Can. J. Chem. Eng., 52, 515-517 (1974)
26) F. Habashi, A Textbook of Hydrometallurgy, Métallurgie Extractive Québec, Sainte-Foy, Quebec 1993, second edition 1999. Distributed by Laval University Bookstore “Zone”
27) F. Habashi, Principles of Extractive Metallurgy, volume 2, Hydrometallurgy, Gordon & Breach, New York-London-Paris 1970 (Reprinted 1980)