Comparative sequence analysis of a recA gene fragment brings new evidence for a change in the taxonomy of the Lactobacillus casei group.

Abstract

T form a single phylogenetic group. The taxonomic status of species and strains at issue is discussed. Keywords : Lactobacillus casei, recA, taxonomyLactobacillus casei and related species include phenotypically and genetically heterogeneous strains able to colonize various natural and man-made environments (Vescovo et al., 1995). Many strains are currently employed as probiotics or mixed cultures for dairy products. Despite its importance for the food industry, the taxonomy of the L. casei group is still unclear. Historically, the systematics of the L. casei group have been problematic and adjustments have been introduced based on new taxonomic methods that have gradually become available. Initially, Hansen & Lessel (1971) designated strain ATCC 393 T as the type strain of L. casei subsp. casei on the basis of a few phenotypic traits. However, Dellaglio et al. (1975) (Dellaglio et al., 1991). The proposal was denied (Wayne, 1994). Dicks et al. (1996) Nour (1998) proposed that 16S-23S and 23S-5S intergenic spacer region sequences might represent a useful alternative to 16S and 23S rDNA for establishing the phylogeny of closely related bacterial species, because of the higher sequence and fragment length polymorphism. Comparative analysis of the 23S-5S rRNA intergenic spacer regions of L. caseirelated strains was performed by Chen et al. (2000). Their observations supported the request of Dellaglio et al. (1991) to replace strain ATCC 393 T with strain ATCC 334 as the neotype of L. casei subsp. casei.

The status of the species Lactobacillus casei (Orla-Jensen 1916) Hansen and Lessel 1971 and Lactobacillus paracasei Collins et al. 1989. Request for an opinion.

“…Furthermore, recent genotypic evidence (Mori et al, 1997 ;Tynkkynen et al, 1999 ;Chen et al, 2000 ;Felis et al, 2001) strongly supports previous indications (Mills & Lessel, 1973 ;Dellaglio et al, 1975Dellaglio et al, , 1991Dicks et al, 1996) that strains ATCC 393 and ATCC 15820 are members of the same taxon. Even though the valid status of the species Lactobacillus zeae was recognized only in 1996 (Dicks et al, 1996), the misidentified strain ATCC 393 is closely related to the type strain of this species.…”

“…tolerans. (3) On the basis that the species Lactobacillus casei has no type strain (see Request 1), we propose strain ATCC 334 as the neotype, since it has been already proposed (Dellaglio et al, 1991 ;Dicks et al, 1996), supported (Mori et al, 1997 ;Tynkkynen et al, 1999 ;Chen et al, 2000 ;Felis et al, 2001) and used as a reference strain (Yoon et al, 2000 ;Cai et al, 1999 ;Morlon-Guyot et al, 1998) (Rule 19). Furthermore, strain LMG 9191 T may be retrieved as the type strain of the subspecies Lactobacillus casei subsp.…”

“…(11) A comparative analysis performed on partial sequences of the recA gene strongly support the view that ATCC 393 and Lactobacillus zeae ATCC 15820 T share a great degree of similarity but are clearly distinct from Lactobacillus casei ATCC 334 and Lactobacillus paracasei strains. Moreover, ATCC 334 and the Lactobacillus paracasei group are genetically very closely related and belong to the same taxon (Felis et al, 2001). …”

Textura instrumental e avaliação sensorial de queijo fresco cremoso simbiótico: implicações da adição de Lactobacillus paracasei e inulina

“…As cepas de Lactobacillus casei/paracasei têm sido amplamente estudadas com relação a suas propriedades promotoras à saú-de, sendo freqüentemente empregadas como probióticos em alimentos industrializados (Stiles, Holzapfel, 1997;Felis et al, 2001;Itsaranuwat et al, 2003;Médici et al, 2004;Vásquez et al, 2005).…”

Analysis, Characterization, and Loci of the tuf Genes in Lactobacillus and Bifidobacterium Species and Their Direct Application for Species Identification

“…In view of its demonstrated effectiveness, sequence analysis of protein-coding genes (e.g., tuf genes) as alternative phylogenetic markers could be added to the arsenal of rRNA sequence databases and to the relatively small groEL (16) and recA (9,22) sequence databases. It has been shown that species having 70% or greater DNA similarity (at the DNA-DNA hybridization or reassociation level) possess in fact more than 97% 16S rDNA sequence identity (43).…”