PMCCPMCCPMCC

Search tips
Search criteria 

Advanced

 
Logo of genannJournal InfoAuthorsPermissionsJournals.ASM.orggenomeA ArticleGenome Announcements
 
Genome Announc. 2017 March; 5(13): e00091-17.
Published online 2017 March 30. doi:  10.1128/genomeA.00091-17
PMCID: PMC5374239

Complete Genome Sequence of Lactobacillus fermentum MTCC 25067 (Formerly TDS030603), a Viscous Exopolysaccharide-Producing Strain Isolated from Indian Fermented Milk

ABSTRACT

Lactobacillus fermentum MTCC 25067 (formerly TDS030603) is capable of producing a highly viscous slime exopolysaccharide. We report here the complete genome sequence of the strain, which was deciphered by using PacBio single-molecule real-time sequencing technology.

GENOME ANNOUNCEMENT

Exopolysaccharide (EPS)-producing lactic acid bacteria (LAB) are of particular interest to the dairy industry, because EPSs can act as natural biothickeners that improve the taste and texture of fermented dairy products (1). Lactobacillus fermentum MTCC 25067 (formerly TDS030603) was isolated from a traditional Indian fermented milk, dahi (2). The strain produces approximately 100 mg [bullet] L−1 of EPS, which is a polymer of a repeating unit composed of three glucose residues and one galactose residue (3). The EPS is expected to be a novel viscosifier originated from LAB, as it showed high viscosity comparable to a commercial viscosifier, xanthan gum (4). A partial structure of the functional EPS gene cluster (accession no. AB519644) in the strain has already been reported to harbor several transposable elements (5).

The genomic DNA of L. fermentum MTCC 25067 was prepared from mid-exponential cultures by the conventional manual extraction method. Sequencing was implemented on the PacBio platform (Pacific Biosciences, Menlo Park, CA, USA). A 20-kb library was prepared using the PacBio DNA template prep kit 1.0, PacBio DNA/polymerase binding kit P6, and BluePippin size selection (Sage Science, Beverly, MA, USA), and then sequenced on a PacBio RSII sequencer using P6-C4 chemistry with one single-molecule real-time (SMRT) cell. After filtering by quality, 107,751 sequences of Q20 accuracy were obtained with a mean read length of 11,144 bp. The filtered sequences were de novo assembled and circularized using the hierarchical genome assembly process (HGAP) protocol version 2.0 in the PacBio SMRT Analysis software package version 2.3.0. As a consequence, two contigs were obtained with around 560× coverage: one represented a circular chromosome with a length of 1,954,694 bp and a G+C content of 51.46%, and another was suggested as a potential linear plasmid (pLF25067) of 57,722 bp with a G+C content of 40.22%.

The assembled genomic sequences were annotated using the DFAST bacterial genome annotation pipeline dedicated to LAB (6). The chromosomal DNA of L. fermentum MTCC 25067 was composed of 2,041 genes, including 1,967 protein-coding genes (CDSs), 15 rRNA operons, 58 tRNAs, and one tmRNA. One clustered regularly interspaced short palindromic repeat cluster (class 1) was found in the chromosome (7). The pLF25067 plasmid contained 53 CDSs, in which triplicate genes encoding RepB and heavy metal transport-related proteins were found, but no RNAs were present. The spaCBA-srtC pilus gene cluster (8, 9) was not found in either the chromosome or the plasmid.

The single slime-like EPS-related gene cluster was found in the chromosome with a size of 20.25 kb encoding one transcriptional regulator LytR ortholog (10), five putative proteins comprising EPS secretion machinery (a tyrosine-protein kinase, a tyrosine-protein phosphatase, Wzx, Wzy, and Wzz) (11), five putative glycosyltransferases, one hypothetical protein, and eight transposable elements. The absence of the transcriptional regulator gene in a previous report (5) seems to be a result of a problem with the genome walking procedure used in that study. The complete genome sequence of L. fermentum MTCC 25067 will aid in further understanding the molecular basis of highly viscous EPS biosynthesis.

Accession number(s).

This whole-genome project has been deposited at DDBJ/EMBL/GenBank under the accession numbers AP017973 and AP017974.

Footnotes

Citation Aryantini NPD, Prajapati JB, Urashima T, Fukuda K. 2017. Complete genome sequence of Lactobacillus fermentum MTCC 25067 (formerly TDS030603), a viscous exopolysaccharide-producing strain isolated from Indian fermented milk. Genome Announc 5:e00091-17. https://doi.org/10.1128/genomeA.00091-17.

REFERENCES

1. Ruas-Madiedo P, de los Reyes-Gavilán CG 2005. Invited review: methods for the screening, isolation, and characterization of exopolysaccharides produced by lactic acid bacteria. J Dairy Sci 88:843–856. doi:.10.3168/jds.S0022-0302(05)72750-8 [PubMed] [Cross Ref]
2. Leo F, Hashida S, Kumagai D, Uchida K, Motoshima H, Arai I, Asakuma S, Fukuda K, Urashima T 2007. Studies on a neutral exopolysaccharide of Lactobacillus fermentum TDS030603. J Appl Glycosci 54:223–229. doi:.10.5458/jag.54.223 [Cross Ref]
3. Gerwig GJ, Dobruchowska JM, Shi T, Urashima T, Fukuda K, Kamerling JP 2013. Structure determination of the exopolysaccharide of Lactobacillus fermentum TDS030603-a revision. Carbohydr Res 378:84–90. doi:.10.1016/j.carres.2013.04.026 [PubMed] [Cross Ref]
4. Fukuda K, Shi T, Nagami K, Leo F, Nakamura T, Yasuda K, Senda A, Motoshima H, Urashima T 2010. Effects of carbohydrate source on physicochemical properties of the exopolysaccharide produced by Lactobacillus fermentum TDS030603 in a chemically defined medium. Carbohydr Polym 79:1040–1045. doi:.10.1016/j.carbpol.2009.10.037 [Cross Ref]
5. Dan T, Fukuda K, Sugai-Bannai M, Takakuwa N, Motoshima H, Urashima T 2009. Characterization and expression analysis of the exopolysaccharide gene cluster in Lactobacillus fermentum TDS030603. Biosci Biotechnol Biochem 73:2656–2664. doi:.10.1271/bbb.90502 [PubMed] [Cross Ref]
6. Tanizawa Y, Fujisawa T, Kaminuma E, Nakamura Y, Arita M 2016. DFAST and DAGA: web-based integrated genome annotation tools and resources. Biosci Microbiota Food Health 35:173–184. doi:.10.12938/bmfh.16-003 [PMC free article] [PubMed] [Cross Ref]
7. Makarova KS, Wolf YI, Alkhnbashi OS, Costa F, Shah SA, Saunders SJ, Barrangou R, Brouns SJ, Charpentier E, Haft DH, Horvath P, Moineau S, Mojica FJ, Terns RM, Terns MP, White MF, Yakunin AF, Garrett RA, van der Oost J, Backofen R, Koonin EV 2015. An updated evolutionary classification of CRISPR-Cas systems. Nat Rev Microbiol 13:722–736. doi:.10.1038/nrmicro3569 [PubMed] [Cross Ref]
8. Douillard FP, Ribbera A, Järvinen HM, Kant R, Pietilä TE, Randazzo C, Paulin L, Laine PK, Caggia C, von Ossowski I, Reunanen J, Satokari R, Salminen S, Palva A, de Vos WM 2013. Comparative genomic and functional analysis of Lactobacillus casei and Lactobacillus rhamnosus strains marketed as probiotics. Appl Environ Microbiol 79:1923–1933. doi:.10.1128/AEM.03467-12 [PMC free article] [PubMed] [Cross Ref]
9. Aleksandrzak-Piekarczyk T, Koryszewska-Bagińska A, Grynberg M, Nowak A, Cukrowska B, Kozakova H, Bardowski J 2015. Genomic and functional characterization of the unusual pLOCK 0919 plasmid harboring the spaCBA pili cluster in Lactobacillus casei LOCK 0919. Genome Biol Evol 8:202–217. doi:.10.1093/gbe/evv247 [PMC free article] [PubMed] [Cross Ref]
10. Lebeer S, Verhoeven TL, Francius G, Schoofs G, Lambrichts I, Dufrêne Y, Vanderleyden J, De Keersmaecker SC 2009. Identification of a gene cluster for the biosynthesis of a long, galactose-rich exopolysaccharide in Lactobacillus rhamnosus GG and functional analysis of the priming glycosyltransferase. Appl Environ Microbiol 75:3554–3563. doi:.10.1128/AEM.02919-08 [PMC free article] [PubMed] [Cross Ref]
11. Islam ST, Lam JS 2014. Synthesis of bacterial polysaccharides via the Wzx/Wzy-dependent pathway. Can J Microbiol 60:697–716. doi:.10.1139/cjm-2014-0595 [PubMed] [Cross Ref]

Articles from Genome Announcements are provided here courtesy of American Society for Microbiology (ASM)