Eleven environmental samples from different sources were screened for the presence of metallo-beta-lactamase-producing bacteria by using a selective enrichment medium containing a carbapenem antibiotic and subsequently testing each isolate for production of EDTA-inhibitable carbapenemase activity. A total of 15 metallo-beta-lactamase-producing isolates, including 10 Stenotrophomonas maltophilia isolates, 3 Chryseobacterium spp., one Aeromonas hydrophila isolate, and one Janthinobacterium lividum isolate (a species in which production of metallo-beta-lactamase activity was not previously reported), were obtained from 8 samples. In the J. lividum isolate, named JAC1, production of metallo-beta-lactamase activity was elicited upon exposure to beta-lactams. Screening of a JAC1 genomic library for clones showing a reduced imipenem susceptibility led to the isolation of a metallo-beta-lactamase determinant encoding a new member (named THIN-B) of the highly divergent subclass B3 lineage of metallo-beta-lactamases. THIN-B is most closely related (35.6% identical residues) to the L1 enzyme of S. maltophilia and more distantly related to the FEZ-1 enzyme of Legionella gormanii (27.8% identity) and to the GOB-1 enzyme of Chryseobacterium meningosepticum (24.2% identity). Sequences related to bla(THIN-B), and inducible production of metallo-beta-lactamase activity, were also detected in the J. lividum type strain DSM1522. Expression of the bla(THIN-B) gene in Escherichia coli resulted in decreased susceptibility to several beta-lactams, including penicillins, cephalosporins (including cephamycins and oxyimino cephalosporins), and carbapenems, revealing a broad substrate specificity of the enzyme. The results of this study indicated that metallo-beta-lactamase-producing bacteria are widespread in the environment and identified a new molecular class B enzyme in the environmental species J. lividum.
Rossolini, G.M., Condemi, M.A., Pantanella, F., Docquier, J., Amicosante, G., & Thaller, M.C. (2001). Metallo-β-lactamase producers in environmental microbiota: New molecular class B enzyme in Janthinobacterium lividum. ANTIMICROBIAL AGENTS AND CHEMOTHERAPY, 45(3), 837-844.
|Tipologia:||Articolo su rivista|
|Citazione:||Rossolini, G.M., Condemi, M.A., Pantanella, F., Docquier, J., Amicosante, G., & Thaller, M.C. (2001). Metallo-β-lactamase producers in environmental microbiota: New molecular class B enzyme in Janthinobacterium lividum. ANTIMICROBIAL AGENTS AND CHEMOTHERAPY, 45(3), 837-844.|
|IF:||Con Impact Factor ISI|
|Settore Scientifico Disciplinare:||Settore BIO/19 - Microbiologia Generale|
Settore MED/07 - Microbiologia e Microbiologia Clinica
|Revisione (peer review):||Esperti anonimi|
|Digital Object Identifier (DOI):||http://dx.doi.org/10.1128/AAC.45.3.837-844.2001|
|Stato di pubblicazione:||Pubblicato|
|Data di pubblicazione:||2001|
|Titolo:||Metallo-β-lactamase producers in environmental microbiota: New molecular class B enzyme in Janthinobacterium lividum|
|Autori:||Rossolini, GM; Condemi, MA; Pantanella, F; Docquier, J.; Amicosante, G; Thaller, MC|
|Appare nelle tipologie:||01 - Articolo su rivista|