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ANALYSIS OF THE COMPLETE GENOME SEQUENCE OF OENOLOGICAL LACTOBACILLUS PLANTARUM UNQLP 11 ISOLATED FROM PATAGONIAN RED WINE

IGLESIAS, Gabriel | BRIZUELA, Natalia | TYMCZYSZYN, Emma Elizabeth | VALDES LA HENS, Danay |

HOLLMANN, Axel | SEMORILE, Liliana | BRAVO FERRADA, Barbara UNIVERSIDAD NACIONAL DE QUILMES

Introduction and objectives: Malolactic fermentation (MLF) is the process responsible for the conversion of L-malic acid to L-lactic acid and CO2, which reduces total acidity, improves biological stability and modifies the aroma profile of the wine. MLF takes place during or after alcoholic fermentation and is carried out by one or more species of lactic acid bacteria (LAB) present in grapes and cellars, or inoculated as malolactic starters. The UNQLp 11 genome is the first complete sequence of a Lb. plantarum isolated from red wines from the southern region of the American Continent. The available genomic information provides us with new opportunities to study the flavor forming potential of this LAB and other important technological properties. We aim to illustrate the natural genomic architecture and the metabolic consequences of UNQLp 11 that is essential to evaluate the potential of this strain as a malolactic starter. Materials and methods: To obtain DNA, 1 mg/ml of lysozyme with 1% sodium dodecyl sulfate was used. Proteins were removed with 0.1 g/ml of proteinase K, followed by phenol-chloroform-isoamyl alcohol (25:24:1) extraction. A total of 16 μg of high-quality genomic DNA was required for library preparation and sequencing. A whole-genome shotgun library was constructed using a 20-kb SMRTbell version 1.0 template prep kit, followed by single-molecule real-time (SMRT) sequencing conducted on an RS II (Pacific Biosciences) sequencer (Macrogen). A total of 1,268,593,327 reads (383,24 -fold coverage and a polymerase read N50 size of 21,044 bp), with an average length of 14,480 bp and an estimated accuracy of 85.5 %, were used as input for de novo assembly with the Canu package. The Canu output consisted of a single circular contig without gaps. Prediction and annotation of coding sequences were conducted with Gene MarkS. Genome annotation was done using the NCBI Prokaryotic Genome Annotation Pipeline. Protein function prediction were done using Blast2GO 5.1.1 Results: UNQLp 11 genome analysis showed the ability for the production of enzymatic activities and metabolites of oenological interest. The importance of our in silico analysis is in guiding future genomics sequencing and experimentation and there by validating our predictions. Conclusions: The chromosomal sequence of the Lb plantarum UNQLp 11 reveals numerous responsible genes for production of metabolites important in the formation of aromas in the production of wine. In addition, the analysis indicates that this strain has the possible to be associated with a wide variety of environments, being able to use different substrates for its growth. That is why, UNQLp11 has the opportunity of being a player as a starter of the MLF. Although the presence of genes does not guarantee its expression during a vinification process, the genome analyses screening allows knowing which strains have the chance to synthesizing enzymes related to aroma production in wine. Finally, the complete genome sequence of Lb. plantarum UNQLp11 may improve our understanding on the FML effects of and extend its potential applications in food fermentation