1. |
Scheirlinck I,
Van der Meulen R,
Van Schoor A,
Vancanneyt M,
De Vuyst L,
Vandamme P,
Huys G,
( 2007 ) Influence of geographical origin and flour type on diversity of lactic acid bacteria in traditional Belgian sourdoughs. PMID : 17675431 : DOI : 10.1128/AEM.00894-07 PMC : PMC2075033 Abstract >>
A culture-based approach was used to investigate the diversity of lactic acid bacteria (LAB) in Belgian traditional sourdoughs and to assess the influence of flour type, bakery environment, geographical origin, and technological characteristics on the taxonomic composition of these LAB communities. For this purpose, a total of 714 LAB from 21 sourdoughs sampled at 11 artisan bakeries throughout Belgium were subjected to a polyphasic identification approach. The microbial composition of the traditional sourdoughs was characterized by bacteriological culture in combination with genotypic identification methods, including repetitive element sequence-based PCR fingerprinting and phenylalanyl-tRNA synthase (pheS) gene sequence analysis. LAB from Belgian sourdoughs belonged to the genera Lactobacillus, Pediococcus, Leuconostoc, Weissella, and Enterococcus, with the heterofermentative species Lactobacillus paralimentarius, Lactobacillus sanfranciscensis, Lactobacillus plantarum, and Lactobacillus pontis as the most frequently isolated taxa. Statistical analysis of the identification data indicated that the microbial composition of the sourdoughs is mainly affected by the bakery environment rather than the flour type (wheat, rye, spelt, or a mixture of these) used. In conclusion, the polyphasic approach, based on rapid genotypic screening and high-resolution, sequence-dependent identification, proved to be a powerful tool for studying the LAB diversity in traditional fermented foods such as sourdough.
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2. |
Bounaix MS,
Robert H,
Gabriel V,
Morel S,
Remaud-Siméon M,
Gabriel B,
Fontagné-Faucher C,
( 2010 ) Characterization of dextran-producing Weissella strains isolated from sourdoughs and evidence of constitutive dextransucrase expression. PMID : 20722740 : DOI : 10.1111/j.1574-6968.2010.02067.x Abstract >>
The study of exopolysaccharide production by heterofermentative sourdough lactic acid bacteria has shown that Weissella strains isolated from sourdoughs produce linear dextrans containing �\-(1��6) glucose residues with few �\-(1��3) linkages from sucrose. In this study, several dextran-producing strains, Weissella cibaria and Weissella confusa, isolated from sourdough, were characterized according to carbohydrate fermentation, repetitive element-PCR fingerprinting using (GTG)(5) primers and glucansucrase activity (soluble or cell-associated). This study reports, for the first time, the characterization of dextransucrase from Weissella strains using sodium dodecyl sulfate-polyacrylamide gel electrophoresis and in situ polymer production (after incubation with sucrose) from enzymatic fractions harvested from both sucrose and glucose culture media. Results demonstrate that dextransucrase activity was mainly soluble and associated with a constitutive 180-kDa protein. In addition, microsequencing of the active dextransucrase from W. cibaria LBAE-K39 allowed the design of specific primers that could detect the presence of glucansucrase encoding genes similar to GTFKg3 of Lactobacillus fermentum Kg3 and to DSRWC of W. cibaria CMU. This study hence indicates that sourdough Weissella strains synthesize original dextransucrase.
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3. |
De Bruyne K,
Camu N,
De Vuyst L,
Vandamme P,
( 2010 ) Weissella fabaria sp. nov., from a Ghanaian cocoa fermentation. PMID : 19801391 : DOI : 10.1099/ijs.0.019323-0 Abstract >>
Two lactic acid bacteria, strains 257(T) and 252, were isolated from traditional heap fermentations of Ghanaian cocoa beans. 16S rRNA gene sequence analysis of these strains allocated them to the genus Weissella, showing 99.5 % 16S rRNA gene sequence similarity towards Weissella ghanensis LMG 24286(T). Whole-cell protein electrophoresis, fluorescent amplified fragment length polymorphism fingerprinting of whole genomes and biochemical tests confirmed their unique taxonomic position. DNA-DNA hybridization experiments towards their nearest phylogenetic neighbour demonstrated that the two strains represent a novel species, for which we propose the name Weissella fabaria sp. nov., with strain 257(T) (=LMG 24289(T) =DSM 21416(T)) as the type strain. Additional sequence analysis using pheS gene sequences proved useful for identification of all Weissella-Leuconostoc-Oenococcus species and for the recognition of the novel species.
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4. |
Kang HK,
Oh JS,
Kim D,
( 2009 ) Molecular characterization and expression analysis of the glucansucrase DSRWC from Weissella cibaria synthesizing a alpha(1-->6) glucan. PMID : 19222580 : DOI : 10.1111/j.1574-6968.2008.01460.x Abstract >>
Weissella cibaria isolated from human saliva produces a soluble glucan that predominantly has alpha-1,6-glucosidic type linkages. Using degenerated primers that were selected based on the amino acid sequences of conserved regions from known glucansucrases, a single 2.7-kb fragment was isolated. In subsequent steps, a 4969-bp product was obtained using inverse PCR. The coding region for the glucansucrase gene (dsrWC) consisted of a 4419-bp ORF that encoded a 1472-amino acid protein with a calculated molecular mass of 161.998 Da. The produced DSRWC glucansucrases exhibited similarity with the enzymes of the glucosylhydrolase family 70, which includes the Lactobacillus fermentum glucansucrase. The expressed recombinant DSRWC (rDSRWC) synthesized oligosaccharides in the presence of maltose or isomaltose as an acceptor and the synthesized products included alpha-1,6-linked glucosyl residues in addition to the maltosyl or isomaltosyl residue. rDSRWC synthesized water-soluble polymers using sucrose as substrate. According to the (13)C-nuclear magnetic resonance analysis, the polymer that was synthesized by rDSRWC was a linear dextran, which formed predominately alpha-1,6-glucosidic linkages. This is the first report on the molecular characterization of glucansucrase from a W. cibaria strain.
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5. |
Park JY,
Jeong SJ,
Sa HD,
Lee JY,
Liu X,
Cho MJ,
Lee KW,
Kim JH,
( 2015 ) Construction of a shuttle vector based on the small cryptic plasmid pJY33 from Weissella cibaria 33. PMID : 25882072 : DOI : 10.1016/j.plasmid.2015.03.008 Abstract >>
A cryptic plasmid, pJY33, from Weissella cibaria 33 was characterized. pJY33 was 2365 bp in size with a GC content of 41.27% and contained two putative open reading frames (ORFs). orf1 encoded a putative hypothetical protein of 134 amino acids. orf2 was 849 bp in size, and its putative translation product exhibited 87% identity with a replication initiation factor from a plasmid from W. cibaria KLC140. A Weissella-Escherichia coli shuttle vector, pJY33E (6.5 kb, Em(r)), was constructed by ligation of pJY33 with pBluescript II SK(-) and an erythromycin resistance gene (Em(r)). pJY33E replicated in Lactococcus lactis, Leuconostoc citreum, Lactobacillus brevis, Lactobacillus plantarum, and Weissella confusa. A single-stranded DNA intermediate was detected from Lb. brevis 2.14 harbouring pJY33E, providing evidence for rolling-circle replication of pJY33. Most Lb. brevis 2.14 cells (85.9%) retained pJY33E after one week of daily culturing in MRS broth without Em. An aga gene encoding �\-galactosidase (�\-Gal) from Leuconostoc mesenteroides was successfully expressed in Lb. brevis 2.14 using pJY33E, and the highest level of �\-Gal activity (36.13 U/mg protein) was observed when cells were grown on melibiose.
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6. |
Lynch KM,
Lucid A,
Arendt EK,
Sleator RD,
Lucey B,
Coffey A,
( 2015 ) Genomics of Weissella cibaria with an examination of its metabolic traits. PMID : 25678547 : DOI : 10.1099/mic.0.000053 Abstract >>
Weissella is a genus of lactic acid bacteria (LAB) consisting of species formerly included in the Leuconostoc paramesenteroides group. Similar to other LAB, they are commonly found in fermented foods but have also been isolated from environmental and human samples. Currently there are 20 recognized species. Herein, three Weissella cibaria genomes were sequenced using Illumia Mi-Seq and Roche 454 technologies. Annotation was performed using the Prokka and JGI IMG pipelines. A thorough analysis of the genomics of the W. cibaria strains was performed, in addition to brief comparative analyses of the genus Weissella as a whole. Genomic sequence data from the newly sequenced W. cibaria strains and data available in GenBank for other Weissella strains was used (n = 10; four Weissella cibaria, one Weissella ceti, one Weissella confusa, one Weissella halotolerans, two Weissella koreensis and one Weissella paramesenteroides). The genomes had sizes varying from 1.3 to 2.4 Mb. DNA G+C contents ranged from 35 to 45 mol%. The core- and pan-proteome at genus and species levels were determined. The genus pan-proteome was found to comprise 4712 proteins. Analysis of the four W. cibaria genomes indicated that the core-proteome, consisting of 729 proteins, constitutes 69 % of the species pan-proteome. This large core-set may explain the divergent niches in which this species has been found. In W. cibaria, in addition to a number of phosphotransferase systems conferring the ability to assimilate plant-associated polysaccharides, an extensive proteolytic system was identified.
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7. |
Malang SK,
Maina NH,
Schwab C,
Tenkanen M,
Lacroix C,
( 2015 ) Characterization of exopolysaccharide and ropy capsular polysaccharide formation by Weissella. PMID : 25475311 : DOI : 10.1016/j.fm.2014.08.022 Abstract >>
With their broad functional properties, lactic acid bacteria derived high molar mass exopolysaccharides (EPS) and oligosaccharides are of great interest for food, medical and pharmaceutical industry. EPS formation by 123 strains of Weissella cibaria and Weissella confusa, was evaluated. Dextran formation from sucrose was observed for all tested strains while 18 strains produced fructan in addition to dextran. Six isolates synthesized a highly ropy polymer from glucose associated with the formation of a cell-bound, capsular polysaccharide (CPS) composed of glucose, O-acetyl groups and two unidentified monomer components. The soluble EPSs of nine strains were identified as low �\-1,3-branched dextran, levan and inulin type polymers using NMR. In addition to glucan and fructan, W. confusa produced gluco- and fructooligosaccharides. Partial dextransucrase and fructansucrase sequences were characterized in the selected Weissella strains. Our study reports the first structural characterization of fructan type EPS from Weissella as well as the first Weissella strain producing inulin. Production of more than one EPS-type by single strains may have high potential for development of applications combining EPS technological and nutritional benefits.
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8. |
Lee KW,
Park JY,
Jeong HR,
Heo HJ,
Han NS,
Kim JH,
( 2012 ) Probiotic properties of Weissella strains isolated from human faeces. PMID : 22200451 : DOI : 10.1016/j.anaerobe.2011.12.015 Abstract >>
Three Weissella confusa and five Weissella cibaria strains were previously isolated from human faeces and their potential as probiotics was examined in this work. Resistance to low pHs (pH 2.0 and 3.0) and 0.3% bile salt were examined. Enzyme activities, susceptibilities to heat treatment and various antibiotics, and adhesion capacities to Caco-2 cells were also examined. All Weissella strains were killed when exposed to pH 2.0 for 2 h but survived at pH 3.0 with different survival ratios. W. confusa 31 survived best (20.2%) and W. confusa 31 was also quite resistant against 0.3% bile salt (128.8%). All strains except one grew well at temperature between 15 and 45 �XC and all strains grew in the presence of 6.5% NaCl. W. confusa 20 showed the highest �]-galactosidase activity (527.3 �� 23.66 unit/mg protein) and W. cibaria 31 had the highest �]-glucosidase activity (115.12 �� 5.3 unit/mg protein) in MRS broth. All strains adhered to Caco-2 cells better than Lactobacillus rhamnosus GG and W. confusa 20 was the best adhesive strain (85 CFU/cell). These results show that some strains such as W. confusa 31 and W. confusa 20 are fully qualified as probiotics and deserve further application studies.
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9. |
( 2013 ) Sequence analysis of a cryptic plasmid pKW2124 from Weissella cibaria KLC140 and construction of a surface display vector. PMID : 23568210 : Abstract >>
Plasmid isolation of kimchi-derived Weissella cibaria KLC140 revealed six different plasmids. The smallest plasmid, pKW2124, was DNA sequenced and characterized, showing 2,124 bp with a GC content of 36.39% and five putative open reading frames (ORFs). In silico analysis of these ORFs showed ORF1 encodes a putative replication protein similar to rolling circular replication proteins from other lactic acid bacteria. However, a single-stranded intermediate was not detected when S1 nuclease was treated, suggesting it may follow theta replication. Interestingly, the replication initiation site of this plasmid is 100% identical to other plasmids from lactic acid bacteria, suggesting it may function for replication initiation. To construct a surface layer expression vector, pTSLGFP, slpA encoding the surface layer protein from Lactobacillus acidophilus was PCR amplified and fused with the gfp gene, forming a SLGFP fused gene. The plasmid pKW2124 was cloned into the XbaI site of pUC19, forming an Weissella-E. coli shuttle vector pKUW22. NheI-linearized pTSLGFP was ligated into pKUWCAT containing pKUW22 and the chloramphenicol acetyltransferase gene from pEK104, resulting in an 8.6 kb pKWCSLGFP surface layer expression vector. After transformation of this vector into W. cibaria KLC140, a GFP fluorescence signal was detected on the surface of the transformant, substantiating production of SLGFP fused protein and its secretion. This is the first report for construction of a Weissella surface layer expression vector, which may be useful for surface layer production of beneficial proteins in Weissella.
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10. |
Linares-Pastén JA,
Falck P,
Albasri K,
Kjellström S,
Adlercreutz P,
Logan DT,
Karlsson EN,
( 2017 ) Three-dimensional structures and functional studies of two GH43 arabinofuranosidases from Weissella sp. strain 142 and Lactobacillus brevis. PMID : 28485897 : DOI : 10.1111/febs.14101 Abstract >>
Arabinofuranosidases degrade arabinose-containing oligo and polysaccharides, releasing l-arabinose, which is a potentially useful sugar, shown to reduce glycemic response under certain conditions. Arabinofuranosidases (Arafs) are frequently found in GH43, one of the most common GH-families encoded in genomes in gut microbiota, and hence it is of interest to increase understanding of the function of these enzymes in species occurring in the gut. Here we have produced, characterized and solved the three-dimensional structures, at 1.9 and 2.0 ? resolution respectively, of two homologous GH43 enzymes, classified under subfamily 26, from Lactobacillus brevis DSM1269 (LbAraf43) and Weissella strain 142 (WAraf43), respectively. The enzymes, with 74% sequence identity to each other, are composed of a single catalytic module with a �]-propeller structure typical of GH43, and an active-site pocket with three identifiable subsites (-1, +1, and +2). According to size exclusion chromatography, native WAraf43 is a dimer, while LbAraf43 is a tetramer in solution. Both of them show activity with similar catalytic efficiency on 1,5-�\-l-arabinooligosaccharides with a degree of polymerization (DP) of 2-3. Activity is restricted to substrates of low DP, and the reason for this is believed to be an extended loop at the entrance to the active site, creating interactions in the +2 subsite. Structural data are available in the PDB under the accession numbers 5M8B (LbAraf43) and 5M8E (WAraf43).
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11. |
( 2012 ) Purification and characterization of beta-glucosidase from Weissella cibaria 37. PMID : 23221534 : Abstract >>
A gene encoding beta-glucosidase was cloned from Weissella cibaria 37, an isolate from human feces. Sequence analysis showed that the gene could encode a protein of 415 amino acids in length, and the translated amino acid sequence showed homology (34-31%) with glycosyl hydrolase family 1 beta-glucosidases. The gene was overexpressed in E. coli BL21(DE3) using pET26b(+) and a 50 kDa protein was overproduced, which matched well with the calculated size of the enzyme, 49,950.87 Da. Recombinant beta-glucosidase was purified by using a his-tag affinity column. The purified beta-glucosidase had an optimum pH and a temperature of 5.5 and 45oC, respectively. Among the metal ions (5mM concentration), Ca2+ slightly increased the activity (108.2%) whereas Cu2+ (46.1%) and Zn2+ (56.7%) reduced the activity. Among the enzyme inhibitors (1 mM concentration), SDS was the strongest inhibitor (16.9%), followed by pepstatin A (45.2%). The Km and Vmax values of purified enzyme were 4.04 mM and 0.92 micromol/min, respectively, when assayed using pNPG (p-nitrophenyl-beta- D-glucopyranoside) as the substrate. The enzyme liberated reducing sugars from carboxymethyl cellulose (CMC).
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