Ulla Margrit Rodrigues

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16S rRNA gene sequencing studies were performed on some unusual gram-positive catalase-negative cocci of unknown taxonomic position isolated from human clinical sources. Comparative analysis of the sequence data demonstrated that the clinical isolates represent a hitherto-unknown line of descent within the low-G+C-content gram-positive bacteria. On the(More)
The 16S ribosomal ribonucleic acid (rRNA) sequences of eleven Enterococcus species were determined by reverse transcription in an attempt to clarify their intrageneric relationships. Comparative analysis of the sequence data revealed the presence of several species groups within the genus. The species E. avium, E. malodoratus, E. pseudoavium and E.(More)
Gram-positive cocci which dominate in the intestinal flora of domestic pigeons were found to constitute a new species of the genus Enterococcus. The strains were most closely related to Enterococcus cecorum, originally described as Streptococcus cecorum, a carboxyphilic species from chicken intestines, and to Enterococcus avium. The pigeon strains resemble(More)
The keeping quality (KQ) of pasteurized milk samples stored at 5 degrees C and 10 degrees C was satisfactorily predicted after 18 h pre-incubation with 0.05% benzalkonium chloride at 20 degrees C, by estimating the numbers of Gram-negative psychrotrophic bacteria using the simple, cheap and rapid (5 min) assay of cytochrome c oxidase. Correlation(More)
The growth patterns of microcolonies of 59 different pure cultures were studied on eight selective solid media. A method of growing microcolonies on the surface of polycarbonate membrane filters, placed on the selective agar media, followed by staining and examination by epifluorescent microscopy was developed. The patterns of growth of the pure cultures as(More)
Taxonomic studies were performed on an anaerobic Gram-positive, spore-forming, psychrophilic bacterium originally isolated from spoiled vacuum-packed refrigerated beef. Based on the present finding it is proposed that this unknown psychrophilic bacterium be classified as a new species of the genus Clostridium, as Clostridium estertheticum sp. nov. The type(More)
A fluorescent antibody-microcolony technique was developed for the rapid detection of salmonellas in pure cultures. Examination of microcolonies made the detection of salmonellas by epifluorescence microscopy easier and more reliable than using fluorescent antibody and single cells. After a study of the most effective selective enrichment media for(More)
With the direct epifluorescent filter technique (DEFT), differentiation of bacteria was achieved by a modified Gram-staining procedure using acridine orange as the counterstain. The method enumerated viable Gram-negative and all Gram-positive bacteria. Counts of clumps of orange fluorescent cells (Gram-negative DEFT count) correlated well with colony counts(More)
The partial 16S rRNA sequences of two unknown human enterococcal isolates were determined by reverse transcription in an attempt to clarify their taxonomic position. The sequence data indicate that they belong to a hitherto unknown species of Enterococcus, for which the name Enterococcus dispar sp. nov. is proposed. The type strain is NCIMB 13000.