Identification, classification, and clinical relevance of catalase-negative, gram-positive cocci, excluding the streptococci and enterococci

Abstract

Several new genera and species of gram-positive, catalase-negative cocci that can cause infections in humans have been described. Although these bacteria were isolated in the clinical laboratory, they were considered nonpathogenic culture contaminants and were not thought to be the cause of any diseases. Isolation of pure cultures of these bacteria from normally sterile sites has led to the conclusion that these bacteria can be an infrequent cause of infection. This review describes the new bacteria and the procedures useful for clinical laboratories to aid in their identification. The clinical relevance and our experience with the various genera and species are reviewed and discussed.

The genus Pediococcus

“…They may cause infections in individuals debilitated as a result of trauma or underlying disease (Mastro et al, 1990;Facklam & Elliot, 1995;Sarma & Mohanty, 1998;Barton et al, 2001). Some strains are resistant to vancomycin and teicoplanin (Swenson et al, 1990;Tankovic et al, 1993;Ammor et al, 2007;Haakensen et al, 2009), which may give them a competitive advantage in medical care environments (Colman & Efstratiou, 1987;Ruoff et al, 1988;Golledge et al, 1990;Mastro et al, 1990;Swenson et al, 1990;Green et al, 1991).…”

Production of Nisin Z by Lactococcus lactis Isolated from Dahi

“…lactis ATCC 19435, the isolate, however, utilized L-arabinose, sucrose, amygdalin, and D-xylose. On the basis of acid production from 49 carbohydrates, the isolate was tentatively identified as L. lactis [19]. The strain was further characterized by sequencing of its PCR-amplified 16S rRNA gene.…”

“…The bacteriocin-producing isolate was identified by its colony morphology, Gram-staining, and biochemical tests [18,19], as well as by 16S rRNA gene sequencing [20]. The isolate was examined for acid production from 49 compounds as sole carbon source using API 50 CH Test kit (BioMerieux, Crappone, France) according to the manufacturer's instructions.…”

Catheter-related Leuconostoc bacteremia secondary to pulmonary Mycobacterium xenopi infection

“…The API 20 strep code was 5214450. Although we were not able to use DNA sequence analysis to confirm this diagnosis, we gave special attention to various biochemical tests to exclude other vancomycin-resistant streptococci, Pediococcus and lactobacilli, using the criteria published in the literature [9,10]: the present strain was pyrrolidonyl arylamidase negative and lacked the enzyme leucine aminopeptidase, whereas arabinose was positive. The strain was not able to hydrolyze arginine.…”