Freezing temperature to freeze-dry cells is a crucial factor for ensuring good wine yeast and LAB survival. These results are important for appropriately preserving micro-organisms and for improving starter production processes.

Three strains of a hitherto-unknown, Gram-stain-positive coccus were recovered from the milk of three non-related healthy women. The isolates shared 99 % 16S rRNA gene sequence similarity with sequences from uncultured members of the Lactobacillales and Streptococcus. The closest sequence corresponding to a defined species was that of Streptococcus peroris GTC 848 T , with a similarity of 98 %. A partial sequence (488 bp) of the tuf gene also showed 97 % similarity with that of S. peroris CCUG 39814 T . The combined 16S rRNA/tuf-based phylogeny revealed that all the isolates grouped in a statistically well-supported cluster separate from S. peroris. Enzyme activity profiles as well as fermentation patterns differentiated the novel bacteria from other members of the Streptococcus mitis group. Finally, phenotypic, genotypic and phylogenetic data supported the proposal of a novel species of the genus Streptococcus, for which the name Streptococcus lactarius sp. nov. is proposed. The type strain is MV1 T (5CECT 7613 T 5DSM 23027 T ).Breast milk is a source of commensal and potentially probiotic bacteria for the infant gut, including streptococci, staphylococci, bifidobacteria and lactic acid bacteria (Heikkilä & Saris, 2003;Martín et al., 2003;Perez et al., 2007; Jiménez et al., 2008a). At the time of writing, the genus Streptococcus consisted of 109 species and 15 subspecies (DSMZ, 2010), most of them belonging to one of the six phylogenetic clusters that have been established based on 16S rRNA gene sequence analysis (Kawamura et al., 1995). Streptococci isolated from human colostrum or milk of healthy women usually belong to the Streptococcus salivarius (S. bovis, S. salivarius) or Streptococcus mitis (S. mitis, S. oralis, S. parasanguinis, S. infantis, S. peroris) groups, as determined by classical phenotypic characteristics and 16S rRNA gene sequencing (Heikkilä & Saris, 2003; Jiménez et al., 2008b; Marín et al., 2009). In addition, streptococcal DNA is also commonly detected in this biological fluid by using molecular techniques such as PCR-DGGE (Delgado et al., 2008) or quantitative real-time PCR (Collado et al., 2009).The members of the mitis group, which includes 12 species (S. mitis, S. pneumoniae, S. pseudopneumoniae, S. oralis, S. infantis, S. australis, S. parasanguinis, S. sanguinis, S. gordonii, S. sinensis, S. cristatus and S. peroris), have traditionally caused considerable confusion for both clinical microbiologists and taxonomists (Facklam, 2002). They are difficult to identify by using biochemical tests due to a lack of reliable and updated biochemical traits (Kawamura et al., 1998). Furthermore, members of the mitis group are closely related to each other genetically, and it is very difficult to differentiate between them even by genetic methods, since some members display more than 99 % 16S rRNA gene sequence similarity and show 40-60 % DNA-DNA relatedness (Kawamura et al., 1995). However, sequencing of other housekeeping genes, such as sodA, rpoB or tuf, has provided useful tools for the identi...

1. Campylobacter jejuni is the most common bacterial cause of human food-borne gastroenteritis in the world. A major source of human infection is the consumption of contaminated meat, particularly poultry. New control measures to reduce or eliminate this pathogen from the animal gastrointestinal tract are urgently required, and the use of probiotics as competitive exclusion agents is a promising biocontrol measure to reduce C. jejuni in the food chain. 2. In this study, we assessed the potential of Lactobacillus johnsonii FI9785, which has shown efficacy against Clostridium perfringens, to combat C. jejuni. The effect of prophylactic administration of L. johnsonii on the ability of C. jejuni to colonise chickens was determined. 3. Two doses of L. johnsonii given a week apart led to a reduction in C. jejuni colonisation in the caecal contents, but this biocontrol seemed reliant upon a high level of initial colonisation by the probiotic. 4. The microbial composition in the chicken gut was significantly altered by the probiotic treatment, as shown by denaturing gradient gel electrophoresis of 16S rRNA gene amplicons. 5. Together these results demonstrate the potential of this probiotic strain to be tested further as a competitive exclusion agent in poultry against C. jejuni.

A Lactobacillus strain, designated 203 T , previously isolated from Bobal grape must was characterized phylogenetically, genotypically and phenotypically in order to establish whether it represents a novel species. On the basis of the 16S rRNA gene sequence, strain 203 T was shown to belong to the genus Lactobacillus, falling within the Lactobacillus alimentariusLactobacillus farciminis group and being closely related to the type strains of L. alimentarius, Lactobacillus kimchii and Lactobacillus paralimentarius. DNA-DNA hybridization results confirmed the separate status of strain 203 T at the species level. To establish the similarities and differences between 203 T and the three aforementioned closest species, the following methods were used: amplified rDNA restriction analysis, analysis of the 16S-23S rDNA intergenic spacer region, random amplification of polymorphic DNA (RAPD) profiling, ribotyping, carbohydrate fermentation and physiological tests. Strain 203 T could be differentiated genetically using RAPD analysis and ribotyping. Phenotypically, it can be distinguished from its closest relatives by its ability to grow at pH 3.3, by gas production from gluconate and by certain carbohydrate fermentations. On the basis of these data, strain 203 T represents a novel species of the genus Lactobacillus, for which the name Lactobacillus bobalius sp. nov. is proposed. The type strain is 203 T (5CECT 7310 T 5DSM 19674 T ).Eighteen different species of the genus Lactobacillus have been reported to be involved in the winemaking process (Chalfan et al., 1977;Costello et al., 1983;Davis et al., 1986;Lafon-Lafourcade, 1983;Lafon-Lafourcade et al., 1983;Maret & Sozzi, 1977, 1979 Ribéreau-Gayon et al., 2000b;Rodas et al., 2005;Wibowo et al., 1985). In recent years, three of them have been described as novel species, namely Lactobacillus kunkeei (Edwards et al., 1998), Lactobacillus nagelii (Edwards et al., 2000) and Lactobacillus vini (Rodas et al., 2006). Wine lactobacilli are sometimes considered as spoilage organisms since they can produce acetic acid and/ or off-flavours Wibowo et al., 1985;Fleet, 1993;Sponholz, 1993) and biogenic amines (Lonvaud Funel, 2001; Ribéreau-Gayon et al., 2000a;Landete et al., 2005).In an earlier study, Rodas et al. (2005) carried out an extensive polyphasic analysis using genotypic and phenotypic methods to characterize 170 lactobacilli isolated from musts and wines. The dendrogram built by comparing the results obtained from the different techniques showed that strain 203 T did not cluster with any of the reference species of the genus Lactobacillus. An analysis of 16S rRNA gene sequence similarity showed that strain 203 T was most closely related to the type strains of Lactobacillus kimchii (99.3 %), Lactobacillus paralimentarius (97.8 %) and Lactobacillus alimentarius (98.2 %). However, the study results did not confirm whether strain 203 T represented a novel species or not.The phylogenetic, genotypic and phenotypic characterization of isolate 203 T and its closest phylogenetic relati...

Ten Lactobacillus strains, previously isolated from different Bobal grape wines from the UtielRequena Origin Denomination of Spain, were characterized phylogenetically, genotypically and phenotypically. The 16S rRNA genes were sequenced and phylogenetic analysis showed that they form a tight phylogenetic clade that is closely related to reference strains Lactobacillus satsumensis NRIC 0604 T , 'Lactobacillus uvarum' 8 and Lactobacillus mali DSM 20444 T . DNA-DNA hybridization results confirmed the separation of the strains from other Lactobacillus species. Genotypically, the strains could be differentiated from their closest neighbours by 16S amplified rDNA restriction analysis and random amplified polymorphic DNA patterns. The strains were Gram-staining-positive, facultatively anaerobic rods that did not exhibit catalase activity. Phenotypically, they could be distinguished from their closest relatives by several traits such as their inabilities to grow at pH 3.3, to ferment sucrose, amygdalin and arbutin or to hydrolyse aesculin. The characteristics of the ten wine isolates suggest that they represent a novel species, for which the name Lactobacillus oeni sp. nov. is proposed. The type strain is 59b T (5CECTLactobacilli are Gram-positive, non-spore-forming, catalase-negative rods belonging to the group of lactic acid bacteria. They are found in a wide variety of habitats such as fermented beverages and foods, mucosal membranes and intestinal tracts of animals and humans, sewage and plant material (Bernardeau et al., 2008). Lactobacilli play an important role in the winemaking process because they can transform a large number of the compounds that are present in wine to the final products that determine a wine's organoleptic properties and, hence, its quality (Lafon-Lafourcade, 1983;Lafon-Lafourcade et al., 1983). Some Lactobacillus species are responsible for malolactic fermentation, although the species Oenococcus oeni is most frequently associated with this process. Malolactic fermentation is a desirable process in the production of quality wines because it reduces acidity, increases microbiological stability and improves organoleptic characteristics (Agouridis et al., 2005). Nevertheless, lactobacilli can also lead to detrimental effects as they can produce acetic acid, off-flavours, ropiness and biogenic amines that can be toxic to humans (Fleet, 1993;Landete et al., 2005Landete et al., , 2007Sponholz, 1993).Because of the positive and negative effects of lactobacilli in wine, several studies have been done in recent years in order to investigate the diversity of Lactobacillus species that are associated with winemaking. As a consequence, some novel Lactobacillus species have been described (Rodas et al., 2006; Mañes-Lázaro et al., 2008a). Following a polyphasic study, Rodas et al. (2005) found a group of ten strains (59b T , 54, 59c, 80, 81, 82, 103, 209g, 376 and 420) that did not cluster with any of the known Lactobacillus species. The 16S rRNA gene of strain 59bT was sequenced and phylogenetic analys...