Genome-wide correlation analysis found that acetic kinases and peptide enzymes were hydrolyzed with the Swiss Lactobacillus protein

。 Original title:
Whole Genome Association Analysis Finds Acetic Kinase and Peptide Enzymes Linked to Swiss Lactobacillus Protein Hydrolysis CapacityRecently, the Key Laboratory of the Ministry of Dairy Biotechnology and Engineering of Inner Mongolia Agricultural University was published in Food Microbiology, a top journal of food microbiology Academic paper entitled "Acetate kinase and peptidases are associated with the proteolytic activity
Lactobacillus helveticus
isolated from fermented food".background:
Swiss Lactobacillus helveticus
,
L. helveticus
) is an important lactic acid bacteria, widely used in the food industry. Its high protein hydrolytic activity can reduce the maturation time of fermentation, promote the production of flavor, reduce the bitter taste in milk fermentation.
properties of
L. helveticus make it an important heat-addicted fermentation agent in industry and are widely used in the production of dairy products such as cheese and fermented milk. During milk fermentation, many important bioactive peptides are released by
L. helveticus
protein hydrolysing.However, the protein hydrolysis capacity of Lactobacillus Of Switzerland varies widely between strains, and the factors that regulate the hydrolysis activity strength of the
L. helveticus
protein are not clear, which hinders the efficiency of screening isolated strains suitable for industrial use.
L. helveticus
high-efficiency protein hydrolysis system consists of cell envelope protease (CEPs), substrate transport system and intracellular peptide enzyme. Some studies have concluded that the heterogeneity and in-plant diversity of CEPs are the main factors that determine
the hydrolytic activity
proteins in cetin. With the development of high-volume sequencing technology, the analysis of
L. helveticus
protein hydrolytic system at the genomic level is helpful to reveal the regulatory mechanism of its protein hydrolytic activity. In this study, the genomes of
L. helveticus
from 60 fermented food sources were sequenced and the factors that influenced the hydrolytic activity of proteins were systematically studied.: Thisanalyzed 60
of L. helveticus
. The strains were collected from Inner Mongolia, Xinjiang, Gansu, Qinghai, Tibet, Yunnan and other places from 2002 to 2009 by the Key Laboratory of the Ministry of Dairy Biotechnology and Engineering of Inner Mongolia Agricultural University. Using high-flung sequencing technology, genome-wide sequencing was performed on 60
L. helveticus
and systematically developed, compared genome and genome-wide association studies (GWAS) to systematically study factors related to protein hydrolytic activity in
L. helveticus
.results of the study: 1.
results of the comparative genome show that
The strength of protein hydrolysis activity
L. helveticus is independent of the source of separation, geographical location, strain affinity, and distribution of cell envelope protease (CEPs).。 The results of the system development tree 2.GWAS analysis based on the core gene of
L. helveticus
isolated strain showed a negative correlation between the protein hydrolytic activity of
L. helveticus
and
ack
A) and positive correlation with 15 identified SNPs.GWAS identified protein hydrolytic activity-related genes and single nucleotide polymorphisms3.
ack
。 A and two cysteine peptidease encoded genes (
pep
C and
srt
A) were associated with protein hydrolyzed activity levels, while high heterogeneity and intrastoplasmic CEPs were not associated with protein hydrolyzed activity levels.。 Using GTAS to analyze the protein hydrolytic activity of isolated strains with/without two protein hydrolytic activity-related genes 4.
protein hydrolytic activity is also associated with the SNP spectrum, with the sequence type (ST) determined by the SNP analysis showing a total of 10 ST, of which the protein hydrolytic activity in the ST2 isolated strain was significantly weaker.。 Based on the protein hydrolysis activity and its clustering pattern (B)summary and prospect of different sequence types (STS) (A) strains based on the single nucleotide polymorphism (SNPs) map this study used 60
L. helveticus
to analyze the factors that affect the strength of protein hydrolysis activity. The results showed that the type, geographical location, strain kinship and distribution of CEPs were not the main factors that determined the difference in hydrolysis activity of
L. helveticus
protein. GWAS results showed a negative correlation between the protein hydrolysis activity of Lactobacillus Suisse and
ack
A) and positive correlation with 15 identified SNPs. In addition, protein hydrolytic activity is also associated with the SNP spectrum. The research provides a theoretical basis for the future screening of Swiss Lactobacillus, which has strong protein hydrolysis activity.The study was published online in November 2020 in Food Microbiology, a top journal of food microbiology (IF2019: 4.155, a regional top journal of the Chinese Academy of Sciences), an associate researcher at First Zhongzhi, Hu Zhicha (a doctoral student); and Chen Yongfu, a researcher in communication.original link: