Chromate reduction by Bacillus megaterium TKW3 isolated from marine sediments

TY - JOUR

T1 - Chromate reduction by Bacillus megaterium TKW3 isolated from marine sediments

AU - Cheung, K. H.

AU - Gu, Ji Dong

N1 - Funding Information: This project was supported by an ITF grant (276/00) from the Innovative Technology Commission of Hong Kong SAR, and industrial partnerships with Kou Hing Hong Scientific Supplies, Peako Engineering Co. We thank Jessie Lai for laboratory assistance and Paula Wang and Li Pan for the DNA sequence alignment.

PY - 2005/4

Y1 - 2005/4

N2 - Bacillus megaterium strain TKW3 was isolated from multiple-metal- contaminated marine sediments of Tokwawan, Hong Kong SAR. This facultative aerobe utilized arabinose, mannitol, N-acetylglucosamine, maltose, caprate, citrate, butyrate or lactate as the sole source of carbon and energy for growth.B. megaterium TKW3 reduced highly toxic and soluble Cr6+ (as CrO 4 2- ) into almost non-toxic and insoluble Cr 3+ under aerobic conditions. Complete reduction of 0.20 mM Cr 6+ by B. megaterium TKW3 was achieved within 360 h. Initial Cr 6+ concentration below 0.90 mM or inoculum less than 107 cells ml-1 did not have significant effect on 6+ reduction, while the residue Cr6+ concentration was the lowest at 107 cells ml-1. Cr6+ reduction by this strain was inhibited by high levels of NaCl (55%). B. megaterium TKW3 was also resistant to other oxyanions including 0.34 mM Cr2 O 7 2- 0.32 mM AsO 4 3- , 0.58 mM SeO 3 2- and 0.53 mM SeO 4 2- , and reduced soluble Se4+ (as SeO 3 2- ) to insoluble red amorphous Se0. B. megaterium TKW3 might have potential application in bioremediation of Cr-laden sediments associated with other oxyanions.

AB - Bacillus megaterium strain TKW3 was isolated from multiple-metal- contaminated marine sediments of Tokwawan, Hong Kong SAR. This facultative aerobe utilized arabinose, mannitol, N-acetylglucosamine, maltose, caprate, citrate, butyrate or lactate as the sole source of carbon and energy for growth.B. megaterium TKW3 reduced highly toxic and soluble Cr6+ (as CrO 4 2- ) into almost non-toxic and insoluble Cr 3+ under aerobic conditions. Complete reduction of 0.20 mM Cr 6+ by B. megaterium TKW3 was achieved within 360 h. Initial Cr 6+ concentration below 0.90 mM or inoculum less than 107 cells ml-1 did not have significant effect on 6+ reduction, while the residue Cr6+ concentration was the lowest at 107 cells ml-1. Cr6+ reduction by this strain was inhibited by high levels of NaCl (55%). B. megaterium TKW3 was also resistant to other oxyanions including 0.34 mM Cr2 O 7 2- 0.32 mM AsO 4 3- , 0.58 mM SeO 3 2- and 0.53 mM SeO 4 2- , and reduced soluble Se4+ (as SeO 3 2- ) to insoluble red amorphous Se0. B. megaterium TKW3 might have potential application in bioremediation of Cr-laden sediments associated with other oxyanions.

KW - Bacillus megaterium

KW - Bioremediation

KW - Chromate reduction

KW - Chromium

KW - Metal resistance

KW - Selenium

UR - http://www.scopus.com/inward/record.url?scp=15944415736&partnerID=8YFLogxK

U2 - 10.1007/s11274-004-3619-9

DO - 10.1007/s11274-004-3619-9

M3 - 文章

AN - SCOPUS:15944415736

SN - 0959-3993

VL - 21

SP - 213

EP - 219

JO - World Journal of Microbiology and Biotechnology

JF - World Journal of Microbiology and Biotechnology

IS - 3

ER -