title: Chromium accumulation by two Streptomyces spp. isolated from riverine sediments.
abstract: Strains designated R22 and R25, isolated from Salí River sediments, Argentina, were highly resistant to chromium. These strains were shown by 16S rRNA sequencing studies to be Streptomyces spp.; this affiliation was consistent with morphological and chemical characteristics. Growth of strains R22 and R25 in medium containing 100 mg l(-1) chromate was reduced by only 23% and 34%, respectively, compared with growth in medium without added chromium. Streptomyces sp. strains R22 and R25 both accumulated chromium with yields of 10.0 and 5.6 mg Cr g(-1) of dry weight, respectively, and a chromate concentration of 50 mg ml(-1). Cell fractionation studies with strain R22 showed that the great majority of the chromium were associated with the cell wall fraction. Streptomyces strains R22 and R25 may have applications in bioremediation of chromium contamination.
authors.affiliation: Instituto de Microbiología, Facultad de Bioquímica, Química y Farmacia, Universidad Nacional de Tucumán, Ayacucho 491, Tucumán 4000, Argentina.
authors.forename: M J
authors.initials: MJ
authors.lastname: Amoroso
authors.forename: G R
authors.initials: GR
authors.lastname: Castro
authors.forename: A
authors.initials: A
authors.lastname: Durán
authors.forename: O
authors.initials: O
authors.lastname: Peraud
authors.forename: G
authors.initials: G
authors.lastname: Oliver
authors.forename: R T
authors.initials: RT
authors.lastname: Hill
mesh_terms: D001673:Biodegradation, Environmental; D002857:Chromium / Q000378:metabolism* / Q000633:toxicity; D004269:DNA, Bacterial / Q000032:analysis / Q000235:genetics; D016521:Electrophoresis, Gel, Pulsed-Field; D005618:Fresh Water / Q000382:microbiology; D019015:Geologic Sediments / Q000382:microbiology*; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D013302:Streptomyces / Q000235:genetics / Q000254:growth & development / Q000302:isolation & purification* / Q000378:metabolism*; D014871:Water Microbiology; D014877:Water Pollution, Chemical
chemical_list: D004269:DNA, Bacterial; D012336:RNA, Ribosomal, 16S; D002857:Chromium