Shanghai Jiao Da Onlly Company Ltd

Shanghai, China

Shanghai Jiao Da Onlly Company Ltd

Shanghai, China
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Luo C.,Shanghai JiaoTong University | Hang X.,Shanghai Jiao Da Onlly Company Ltd | Liu X.,Shanghai JiaoTong University | Zhang M.,Shanghai JiaoTong University | And 3 more authors.
Annals of Microbiology | Year: 2015

Forty-six strains from a collection of human bifidobacteria stored in our lab, each belonging to Bifidobacterium longum subsp. longum species and displaying unique Multilocus sequencing typing (MLST) profiles, were chosen to assess an antibiotic resistance pattern. Three B. longum strains were found to be macrolide-lincosamide-streptogramin B (MLS)-resistant; erm(X) determinants were detected in genomic DNA, and two acquired erm(X) determinants by Tn5432 transposition. A complete sequence of Tn5432 in the bifidobacteria genome was obtained for the first time. The transposon Tn5432 in the Bifidobacterium longum subsp. longum SQS4-63 genome was located between the NTP pyrophosphatase and pyruvate kinase genes, and the insertion created an 8 bp duplication of the target sequence (GATAACGA). © 2015, Springer-Verlag Berlin Heidelberg and the University of Milan.


Wang N.,Shanghai JiaoTong University | Hang X.,Shanghai Jiao Da Onlly Company Ltd | Zhang M.,Shanghai JiaoTong University | Zhang M.,Shanghai Jiao Da Onlly Company Ltd | And 2 more authors.
Scientific Reports | Year: 2017

Due to tetracycline abuse, the safe bifidobacteria in the human gastrointestinal intestinal tract (GIT) may serve as a reservoir of tetracycline resistance genes. In the present investigation of 92 bifidobacterial strains originating from the human GIT, tetracycline resistance in 29 strains was mediated by the tet(W), tet(O) or tet(S) gene, and this is the first report of tet(O)- and tet(S)-mediated tetracycline resistance in bifidobacteria. Antibiotic resistance genes harbored by bifidobacteria are transferred from other bacteria. However, the characteristics of the spread and integration of tetracycline resistance genes into the human intestinal bifidobacteria chromosome are poorly understood. Here, conserved sequences were identified in bifidobacterial strains positive for tet(W), tet(O), or tet(S), including the tet(W), tet(O), or tet(S) and their partial flanking sequences, which exhibited identity with the sequences in multiple human intestinal pathogens, and genes encoding 23 S rRNA, an ATP transporter, a Cpp protein, and a membrane-spanning protein were flanking by the 1920-bp tet(W), 1920-bp tet(O), 1800-bp tet(O) and 252-bp tet(S) in bifidobacteria, respectively. These findings suggest that tetracycline resistance genes harbored by human intestinal bifidobacteria might initially be transferred from pathogens and that each kind of tetracycline resistance gene might tend to insert in the vicinity of specific bifidobacteria genes. © 2017 The Author(s).


Liu Q.,Shanghai JiaoTong University | Hang X.,Shanghai Jiao Da Onlly Company Ltd | Liu X.,Shanghai JiaoTong University | Tan J.,Shanghai JiaoTong University | And 2 more authors.
Annals of Microbiology | Year: 2012

Many of the species of Lactobacillus can be considered to be "probiotics" with a variety of benefits, including imparting antioxidative effects to the host. Lactobacillus species evolve different mechanisms to defend themselves against oxygen toxicity, such as superoxide dismutases (SODs), hydroperoxidases and high intracellular levels of metal ions. The SODs provide a cellular defense mechanism against oxidative stress by scavenging O 2 -. Most Lactobacillus species appear to lack a sod gene. To date, only two species of Lactobacillus (Lactobacillus casei and L. sakei) may have sod genes, as evidenced by sequence analysis of the genome, but no experimental verification, including cloning and heterologous expression of the Lactobacillus sod gene, has been reported. It is therefore unknown whether these sod genes can express SOD or are functional. We have PCR-amplified the gene from L. casei Lc18 that encodes the SOD using primers designed according to the genome of L. casei ATCC 334 and ligated it into the vector pET-28a(+) for heterologous expression in Escherichia coli BL21(DE3). After being induced with IPTG, the fusion protein was efficiently expressed in a soluble form. The superoxide radical scavenging activity of the recombinant strain was found to be increased relative to that of the control strain. The SOD was also purified by nickel ion affinity chromatography and found to consist of a single band, as determined by SDS-PAGE analysis, with an activity of 39.97 U/mg. N-terminal amino acid sequence analysis indicated that it may be a manganese-containing SOD. This is the first report of a sod gene from Lactobacillus spp. being expressed in other prokaryotes. © Springer-Verlag and the University of Milan 2011.


Liao Q.,Shanghai JiaoTong University | Hang X.,Shanghai Jiao Da Onlly Company Ltd | Liu X.,Shanghai JiaoTong University | Pan J.,Shanghai JiaoTong University | And 2 more authors.
Annals of Microbiology | Year: 2010

The influence of pH on the heat stress response of a human-derived probiotic strain of Lactobacillus plantarum, LP-Onlly, was investigated. The heat resistance of mid-log- and stationary-phase cells that were heatadapted (45°C) in cultures that were or were not pH adjusted (pH 4.3-7.0) was evaluated at a lethal temperature of 55°C. The results demonstrated that the heat resistance of heat-adapted stationary-phase cells increased sharply as the pH for heat adaptation in cultures was adjusted from pH 4.3 (non-adjusted pH) to pH 7.0 step by step (pH 5.0, 5.5, 6.0, 6.5, and 7.0); however, the mid-log-phase cells did not show the similar pH-related trend. The optimal adjusted pH for heat adaptation in cultures was found to be 6.5, with stationary-phase cells that were heat-adapted at pH 6.5 exhibiting a 3.4-log-cycle increase in heat resistance and 6-fold greater storage stability than controls. Real-time reverse transcription PCR analysis of five major heat shock protein genes (dnak, dnaJ, grpE, groES, and groEL) revealed that the heat-inductive expression of these genes after heat adaptation was up-regulated in stationary-phase cells when the pH in cultures for heat adaptation was adjusted from 4.3 (non-adjusted pH) to 6.5. Nevertheless, the transcription levels of these genes after heat adaptation was down-regulated in mid-log-phase cells when the pH in cultures for heat adaptation was shifted from 6.0 (nonadjusted pH) to 6.5. © Springer-Verlag and the University of Milan 2010.


Jiang J.,Shanghai JiaoTong University | Hang X.,Shanghai Jiao da Onlly Co. | Zhang M.,Shanghai Jiao da Onlly Co. | Liu X.,Shanghai JiaoTong University | And 2 more authors.
Annals of Microbiology | Year: 2010

This study was conducted to evaluate the diversity of bile salt hydrolase (BSH) activities in eight species of lactobacilli. BSH activities were quantified based on the amount of taurine or glycine liberated from six main human bile sodium salts [glycocholic, glycodeoxycholic, glycochenodeoxycholic, taurocholic (TC), taurochenodeoxycholic, taurodeoxycholic] and a mixture of bile salts that resembled human bile. The eight species differed in their BSH activities. Specifically, Lactobacillus helveticus, Lactobacillus fermentum and Lactobacillus gallinarum had the ability to deconjugate taurine-conjugated bile salts, but not glycine-conjugated bile salts, which suggested that microbial BSHs recognize bile salts on both the cholate steroid nucleus and the amino acid moiety. Of the eight species evaluated, Lactobacillus acidophilus strains exhibited the highest specific BSH activity toward human bile salts, with the exception of TC. In addition, the L. acidophilus specific BSH activity toward glycine-conjugated bile salts was ten times higher than that toward taurine-conjugated bile salts. Moreover, the specific BSH activity of Lactobacillus plantarum did not vary significantly toward different bile salts, and Lactobacillus gasseri Am1 exhibited higher specific BSH activity toward TC than other lactobacilli. A comparison of bsh genes indicated that the LA-bshA, LA-bshB, LG-bsh and LP-bsh1 genes that encode the BSH enzymes are highly homologous (higher than 45%), while the LP-bsh2, LP-bsh3 and LP-bsh4 genes, which might not encode BSH enzymes, had lower similarity (lower than 26.3%). © 2009 Springer-Verlag and the University of Milan.


Zhang M.,Shanghai JiaoTong University | Zhang M.,Shanghai Jiao Da Onlly Company Ltd | Hang X.,Shanghai Jiao Da Onlly Company Ltd | Tan J.,Shanghai JiaoTong University | Yang H.,Shanghai JiaoTong University
Applied and Environmental Microbiology | Year: 2015

To investigate the influences of host genotype and environment on Bifidobacterium longum subsp. longum inhabiting human intestines at the strain level, six pairs of twins, divided into two groups (children and adults), were recruited. Each group consisted of two monozygotic (MZ) twin pairs and one dizygotic (DZ) twin pair. Child twins had been living together from birth, while adult twins had been living separately for 5 to 10 years. A total of 345 B. longum subsp. longum isolates obtained from 60 fecal samples from these twins were analyzed by multilocus sequence typing (MLST), and 35 sequence types (STs) were finally acquired. Comparison of strains within and between the twin pairs showed that no strains with identical STs were observed between unrelated individuals or within adult DZ twin pairs. Eight STs were found to be monophyletic, existing within MZ twins and child DZ twins. The similarity of strain types within child cotwins was significantly higher than that within adult cotwins, which indicated that environment was one of the important determinants in B. longum subsp. longum strain types inhabiting human intestines. However, although these differences between MZ and DZ twins were observed, it is still difficult to reach an exact conclusion about the impact of host genotype. This is mainly because of the limited number of subjects tested in the present study and the lack of strain types tracing in the same twin pairs from birth until adulthood. © 2015, American Society for Microbiology.


Yang X.,Shanghai JiaoTong University | Hang X.,Shanghai Jiao Da Onlly Company Ltd | Tan J.,Shanghai JiaoTong University | Yang H.,Shanghai JiaoTong University
Anaerobe | Year: 2015

Bifidobacteria are common inhabitants of the human gastrointestinal tract, and their application has increased dramatically in recent years due to their health-promoting effects. The ability of bifidobacteria to tolerate acidic environments is particularly important for their function as probiotics because they encounter such environments in food products and during passage through the gastrointestinal tract. In this study, we generated a derivative, Bifidobacterium breve BB8dpH, which displayed a stable, acid-resistant phenotype. To investigate the possible reasons for the higher acid tolerance of B.breve BB8dpH, as compared with its parental strain B.breve BB8, a combined transcriptome and physiological approach was used to characterize differences between the two strains. An analysis of the transcriptome by RNA-sequencing indicated that the expression of 121 genes was increased by more than 2-fold, while the expression of 146 genes was reduced more than 2-fold, in B.breve BB8dpH. Validation of the RNA-sequencing data using real-time quantitative PCR analysis demonstrated that the RNA-sequencing results were highly reliable. The comparison analysis, based on differentially expressed genes, suggested that the acid tolerance of B.breve BB8dpH was enhanced by regulating the expression of genes involved in carbohydrate transport and metabolism, energy production, synthesis of cell envelope components (peptidoglycan and exopolysaccharide), synthesis and transport of glutamate and glutamine, and histidine synthesis. Furthermore, an analysis of physiological data showed that B.breve BB8dpH displayed higher production of exopolysaccharide and lower H+-ATPase activity than B.breve BB8. The results presented here will improve our understanding of acid tolerance in bifidobacteria, and they will lead to the development of new strategies to enhance the acid tolerance of bifidobacterial strains. © 2015 Elsevier Ltd.


Yang X.,Shanghai JiaoTong University | Hang X.,Shanghai Jiao Da Onlly Company Ltd | Zhang M.,Shanghai JiaoTong University | Zhang M.,Shanghai Jiao Da Onlly Company Ltd | And 2 more authors.
Applied Microbiology and Biotechnology | Year: 2015

The acid tolerance is particularly important for bifidobacteria to function as probiotics because they usually encounter acidic environments in food products and gastrointestinal tract passage. In this study, two acid-resistant derivatives Bifidobacterium longum JDY1017dpH and Bifidobacterium breve BB8dpH, which displayed a stable acid-resistant phenotype, were generated. The relationship between acid tolerance and cell membrane was investigated by comparing the two acid-resistant derivatives and their parental strains grown in medium with and without Tween 80. The fold increase in acid tolerance of the two acid-resistant derivatives relative to their parental strains was much higher when cells were grown in medium with Tween 80 (104 ~ 105-fold) than without Tween 80 (181- and 245-fold). Moreover, when cells were grown in medium with Tween 80, the two acid-resistant derivatives exhibited more C18:1 and cycC19:0, higher mean fatty acid chain length, lower membrane fluidity, and higher expression of cfa gene encoding cyclopropane fatty acid synthase than their parental strains. No significant differences in cell membrane were observed between the two acid-resistant derivatives and their parental strains when cells were grown in medium without Tween 80. The present study revealed that, when cells were grown in medium with Tween 80, the significant fold increase in acid tolerance of the two acid-resistant derivatives was mainly ascribed to the pronounced changes in cell membrane compared with their parental strains. Results presented here could provide a basis for developing new strategies of cell membrane modification to enhance acid tolerance in bifidobacteria. © 2015, Springer-Verlag Berlin Heidelberg.


PubMed | Shanghai Jiao Da Onlly Company Ltd and Shanghai JiaoTong University
Type: | Journal: Anaerobe | Year: 2015

Bifidobacteria are common inhabitants of the human gastrointestinal tract, and their application has increased dramatically in recent years due to their health-promoting effects. The ability of bifidobacteria to tolerate acidic environments is particularly important for their function as probiotics because they encounter such environments in food products and during passage through the gastrointestinal tract. In this study, we generated a derivative, Bifidobacterium breve BB8dpH, which displayed a stable, acid-resistant phenotype. To investigate the possible reasons for the higher acid tolerance of B.breve BB8dpH, as compared with its parental strain B.breve BB8, a combined transcriptome and physiological approach was used to characterize differences between the two strains. An analysis of the transcriptome by RNA-sequencing indicated that the expression of 121 genes was increased by more than 2-fold, while the expression of 146 genes was reduced more than 2-fold, in B.breve BB8dpH. Validation of the RNA-sequencing data using real-time quantitative PCR analysis demonstrated that the RNA-sequencing results were highly reliable. The comparison analysis, based on differentially expressed genes, suggested that the acid tolerance of B.breve BB8dpH was enhanced by regulating the expression of genes involved in carbohydrate transport and metabolism, energy production, synthesis of cell envelope components (peptidoglycan and exopolysaccharide), synthesis and transport of glutamate and glutamine, and histidine synthesis. Furthermore, an analysis of physiological data showed that B.breve BB8dpH displayed higher production of exopolysaccharide and lower H(+)-ATPase activity than B.breve BB8. The results presented here will improve our understanding of acid tolerance in bifidobacteria, and they will lead to the development of new strategies to enhance the acid tolerance of bifidobacterial strains.

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