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Sun Z,
Harris HM,
McCann A,
Guo C,
Argimón S,
Zhang W,
Yang X,
Jeffery IB,
Cooney JC,
Kagawa TF,
Liu W,
Song Y,
Salvetti E,
Wrobel A,
Rasinkangas P,
Parkhill J,
Rea MC,
O'Sullivan O,
Ritari J,
Douillard FP,
Paul Ross R,
Yang R,
Briner AE,
Felis GE,
de Vos WM,
Barrangou R,
Klaenhammer TR,
Caufield PW,
Cui Y,
Zhang H,
O'Toole PW,
( 2015 ) Expanding the biotechnology potential of lactobacilli through comparative genomics of 213 strains and associated genera. PMID : 26415554 : DOI : 10.1038/ncomms9322 PMC : PMC4667430 Abstract >>
Lactobacilli are a diverse group of species that occupy diverse nutrient-rich niches associated with humans, animals, plants and food. They are used widely in biotechnology and food preservation, and are being explored as therapeutics. Exploiting lactobacilli has been complicated by metabolic diversity, unclear species identity and uncertain relationships between them and other commercially important lactic acid bacteria. The capacity for biotransformations catalysed by lactobacilli is an untapped biotechnology resource. Here we report the genome sequences of 213 Lactobacillus strains and associated genera, and their encoded genetic catalogue for modifying carbohydrates and proteins. In addition, we describe broad and diverse presence of novel CRISPR-Cas immune systems in lactobacilli that may be exploited for genome editing. We rationalize the phylogenomic distribution of host interaction factors and bacteriocins that affect their natural and industrial environments, and mechanisms to withstand stress during technological processes. We present a robust phylogenomic framework of existing species and for classifying new species.
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Llamas-Arriba MG,
Pérez-Ramos A,
Puertas AI,
López P,
Dueñas MT,
Prieto A,
( 2018 ) Characterization of Pediococcus ethanolidurans CUPV141: A �]-D-glucan- and Heteropolysaccharide-Producing Bacterium. PMID : 30233527 : DOI : 10.3389/fmicb.2018.02041 PMC : PMC6131198 Abstract >>
Pediococcus ethanolidurans CUPV141 is an exopolysaccharide (EPS)-producing lactic acid bacterium, first isolated from Basque Country cider (Spain). Physicochemical analysis of the EPS synthesized by the bacterium revealed that CUPV141 produces mostly a homopolysaccharide (HoPS), characterized as a 2-substituted (1,3)-�]-D-glucan, together with a small quantity of a heteropolysaccharide (HePS) composed of glucose, galactose, glucosamine, and glycerol-3-phosphate, this being the first Pediococcus strain described to produce this kind of polymer. On the contrary, an isogenic strain CUPV141NR, generated by chemical mutagenesis of CUPV141, produced the HePS as the main extracellular polysaccharide and a barely detectable amount of 2-substituted (1,3)-�]-D-glucan. This HoPS is synthesized by the transmembrane GTF glycosyltransferase (GTF), encoded by the gtf gene, which has been previously reported to be located in the pPP2 plasmid of the Pediococcus parvulus 2.6 strain. Southern blot hybridization revealed that in CUPV141 the gtf gene is located in a plasmid designated as pPE3, whose molecular mass (34.4 kbp) is different from that of pPP2 (24.5 kbp). Analysis of the influence of the EPS on the ability of the producing bacteria to adhere to the eukaryotic Caco-2 cells revealed higher affinity for the human enterocytes of CUPV141NR compared to that of CUPV141. This result indicates that, in contrast to the 2.6 strain, the presence of the HoPS does not potentiate the binding ability of P. ethanolidurans. Moreover, it supports that the phosphate-containing bacterial HePS improved the interaction between P. ethanolidurans and the eukaryotic cells.
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