No abstract

Lactobacillus algidus sp. nov. is described on the basis of 40 strains isolated as one of the predominant bacteria from five specimens of vacuum-packaged beef collected from different meat shops and stored at 2 SC for 3 weeks. These strains were quite uniform in the overall characteristics examined. They are facultatively anaerobic, psychrophilic, Gram-positive, non-spore-forming, nonmotile, lactic acid-homofermentative rods. The cells occurred singly and in pairs on agar media and in rather long chains in broth media. They differed in several cultural and biochemical characteristics from the authentic mesodiaminopimelic acid-positive or psychrophilic lactic acid bacteria in the genera Lactobacillus, Carnobacterium and Brochothrix. The SDS-PAGE whole-cell protein pattern was clearly distinctive. DNA-DNA hybridization and phylogenetic analysis of 16S rDNA also failed to associate these strains closely with any of the validly described organisms used. The phylogenetic analysis showed that these strains are rather remotely but most closely related to Lactobacillus mali (93 % sequence similarity), which belongs to the Lactobacillus casei/Pediococcus group. Therefore, these strains should be included in the genus Lactobacillus and considered to represent a new species, Lactobacillus algidus sp. nov. The type strain is M6A9 T (l JCM 10491 T ).

Aims: To characterize Gram‐positive, catalase‐negative, psychrotrophic, lactic acid‐homofermentative, non‐motile cocci isolated from vacuum‐packaged refrigerated beef using phenotypic and genotypic methods. Methods and Results: A total of 89 strains was isolated at 2 and 6 weeks as one of the predominant microflora of five samples of vacuum‐packaged beef stored at 2°C. The strains were compared with reference strains of some Gram‐positive, catalase‐negative cocci using SDS‐PAGE whole‐cell protein pattern analysis, biochemical characterization and 16S rDNA sequencing. The biochemical and physiological characteristics of the isolates resembled those of Lactococcus piscium GTC 552T. Numerical analysis of the SDS‐PAGE whole‐cell protein patterns resulted in close clustering of the strains with L. piscium GTC 552T (r > 0·68). Other Lactococcus and Leuconostoc species could be distinguished from the isolates using SDS‐PAGE whole‐cell protein patterns (r < 0·58) and biochemical characteristics. The 16S rDNA sequencing of four randomly selected strains showed that the strains differed from L. piscium GTC 552T by two to three bases in the highly variable region of the sequence. This is the first report on the isolation of L. piscium from vacuum‐packaged beef. Conclusions: The Gram‐positive catalase‐negative cocci isolated from vacuum‐packaged refrigerated beef have been identified as L. piscium. Significance and Impact of the Study: The findings of this work contribute to the knowledge of the microflora of vacuum‐packaged refrigerated beef.

No abstract