TY - JOUR
T1 - Microbial recovery of vanadium by the acidophilic bacterium, Acidocella aromatica
AU - Okibe, Naoko
AU - Maki, Masashi
AU - Nakayama, Daisuke
AU - Sasaki, Keiko
N1 - Funding Information:
This work was partly supported by Grants from the Japan Society for the Promotion of Science (JSPS: No. 23810024; 26820394) and Arai Science and Technology Foundation. The XAFS experiments were performed at the SAGA Light Source (Kyushu University Beam Line; BL06, No. 2013IIK018). SEM and TEM observations were carried out at the Research Laboratory for High Voltage Electron Microscopy, Kyushu University. Acidocella aromatica PFBC was kindly provided by Prof. D. B. Johnson (Bangor University, UK).
Publisher Copyright:
© 2016, Springer Science+Business Media Dordrecht.
PY - 2016/9/1
Y1 - 2016/9/1
N2 - Objective: To investigate the bioreduction of toxic pentavalent vanadium [vanadate; V(V)] in the acidophilic, Fe(III)-reducing obligately heterotrophic bacterium, Acidocella aromatica PFBC. Results: Although the initial lag-phase of growth became extended with increasing initial V(V) concentrations, the final cell density during aerobic growth of A. aromatica PFBC was unaffected by up to 2 mM V(V). While strain PFBC is an aerobe, growth-decoupled PFBC cell suspensions directly reduced V(V) using fructose, both micro-aerobically and anaerobically, under highly acidic (pH 2) and moderately acidic (pH 4.5) conditions. Bio reduced V(IV) was subsequently precipitated even under micro-aerobic conditions, mostly by encrusting the cell surface. An anaerobic condition at pH 4.5 was optimal for forming and maintaining stable V(IV)-precipitates. Recovery of approx. 70 % of V(V) from the solution phase was made possible with V(V) at 1 mM. Conclusions: The first case of direct V(V) reducing ability and its subsequent V recovery from the solution phase was shown in acidophilic prokaryotes. Possible utilities of V(V) bioreduction in acidic conditions, are discussed.
AB - Objective: To investigate the bioreduction of toxic pentavalent vanadium [vanadate; V(V)] in the acidophilic, Fe(III)-reducing obligately heterotrophic bacterium, Acidocella aromatica PFBC. Results: Although the initial lag-phase of growth became extended with increasing initial V(V) concentrations, the final cell density during aerobic growth of A. aromatica PFBC was unaffected by up to 2 mM V(V). While strain PFBC is an aerobe, growth-decoupled PFBC cell suspensions directly reduced V(V) using fructose, both micro-aerobically and anaerobically, under highly acidic (pH 2) and moderately acidic (pH 4.5) conditions. Bio reduced V(IV) was subsequently precipitated even under micro-aerobic conditions, mostly by encrusting the cell surface. An anaerobic condition at pH 4.5 was optimal for forming and maintaining stable V(IV)-precipitates. Recovery of approx. 70 % of V(V) from the solution phase was made possible with V(V) at 1 mM. Conclusions: The first case of direct V(V) reducing ability and its subsequent V recovery from the solution phase was shown in acidophilic prokaryotes. Possible utilities of V(V) bioreduction in acidic conditions, are discussed.
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U2 - 10.1007/s10529-016-2131-2
DO - 10.1007/s10529-016-2131-2
M3 - Article
C2 - 27230938
AN - SCOPUS:84970015949
SN - 0141-5492
VL - 38
SP - 1475
EP - 1481
JO - Biotechnology Letters
JF - Biotechnology Letters
IS - 9
ER -