PubMed · 1404949
The source did not provide an abstract. Follow the original record for more information.
Explore connections, maps & timelines
C Nakahama. 1992. [Microplate hybridization method].. https://pubmed.ncbi.nlm.nih.gov/1404949/
Cite the original work for its findings. Save a collection to share your selection of sources.
KEEP EXPLORING
Explore the source record for details and available documents.
Five pathogenic strains each of Staphylococcus epidermidis, S. haemolyticus, S. lugdunensis and S. schleiferi were analysed by conventional electrophoresis and field inversion gel electrophoresis. For these coagulase-negative staphylococci, the restriction endonuclease SmaI emerged as the most suitable enzyme for pulsed-field electrophoresis by providing an adequate number of clearly separated DNA fragments. Field inversion gel electrophoresis confirmed the differences among strains already discriminated by conventional electrophoresis, and furthermore, differentiated strains which had previously appeared identical. Among the species that were studied, S. epidermidis showed great genomic diversity with a few common bands. On the contrary, S. haemolyticus, S. lugdunensis and S. schleiferi showed less diversity. Although these minor variations may be epidemiologically significant, this question has to be investigated on a larger number of strains.
Three different beta-lactamase substrate profiles were identified in 95 isolates of coagulase-negative staphylococci (CNS), of 57 different phenotypes, from 16 orthopaedic inpatients and staff members in one ward, by applying a bacterial whole-cell assay based on the hydrolysis of cefazolin, cephaloridine and nitrocefin. The typability of the assay was 93%, and 91% of the CNS isolates could be classified. To assess the discrimination between the beta-lactamase profiles obtained in the whole-cell assay, beta-lactamase extracts from 19 of the CNS isolates were used for estimation of their relative beta-lactamase substrate affinity index (RSAI). The RSAI assay was able to type previously unclassifiable or nontypable isolates. Two of the profiles obtained with the whole-cell assay were similar to those of the Staphylococcus aureus controls producing A or D and B or C beta-lactamases respectively. The distribution of beta-lactamase substrate profiles among the CNS isolates indicated an efficient spread of these drug resistance genes.