Isolation and Characterization of Four Gram-Positive Nickel-Tolerant Microorganisms from Contaminated Sediments

Journal Article · Mon Jan 01 04:00:00 EST 2007 · Microbial Ecology

DOI:https://doi.org/10.1007/s00248-006-9160-7· OSTI ID:908664

Van Nostrand, J. D.; Khijniak, T. V.; Gentry, T. J.; Novak, M. T.; Sowder, A. G.; Zhou, J. Z.; Bertsch, P. M.; Morris, P. J.

Microbial communities from riparian sediments contaminated with high levels of Ni and U were examined for metal-tolerant microorganisms. Isolation of four aerobic Ni-tolerant, Gram-positive heterotrophic bacteria indicated selection pressure from Ni. These isolates were identified as Arthrobacter oxydans NR-1, Streptomyces galbus NR-2, Streptomyces aureofaciens NR-3, and Kitasatospora cystarginea NR-4 based on partial 16S rDNA sequences. A functional gene microarray containing gene probes for functions associated with biogeochemical cycling, metal homeostasis, and organic contaminant degradation showed little overlap among the four isolates. Fifteen of the genes were detected in all four isolates with only two of these related to metal resistance, specifically to tellurium. Each of the four isolates also displayed resistance to at least one of six antibiotics tested, with resistance to kanamycin, gentamycin, and ciprofloxacin observed in at least two of the isolates. Further characterization of S. aureofaciens NR-3 and K. cystarginea NR-4 demonstrated that both isolates expressed Ni tolerance constitutively. In addition, both were able to grow in higher concentrations of Ni at pH 6 as compared with pH 7 (42.6 and 8.5 mM Ni at pH 6 and 7, respectively). Tolerance to Cd, Co, and Zn was also examined in these two isolates; a similar pH-dependent metal tolerance was observed when grown with Co and Zn. Neither isolate was tolerant to Cd. These findings suggest that Ni is exerting a selection pressure at this site for metal-resistant actinomycetes.

• Research Organization: Savannah River Ecology Laboratory (SREL), Aiken, SC
• Sponsoring Organization: USDOE
• DOE Contract Number: FC09-07SR22506
• OSTI ID: 908664
• Report Number(s): SREL-3033
• Journal Information: Microbial Ecology, Journal Name: Microbial Ecology Vol. 53; ISSN MCBEBU; ISSN 0095-3628
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
60 APPLIED LIFE SCIENCES
ANTIBIOTICS
BACTERIA
COMMUNITIES
FUNCTIONALS
GENES
HOMEOSTASIS
MICROORGANISMS
PROBES
SEDIMENTS
STREPTOMYCES
TELLURIUM
TOLERANCE