Characterization of the Adaptive Amoxicillin Resistance of Lactobacillus casei Zhang by Proteomic Analysis

Abstract

Amoxicillin is one of the most commonly prescribed antibiotics for bacterial infections and gastrointestinal disorders. To investigate the adaptation of Lactobacillus (L.) casei Zhang to amoxicillin stress, an iTRAQ-based comparative proteomic analysis was performed to compare the protein profiles between the parental L. casei Zhang and its amoxicillin-resistant descendent strains. Our results revealed a significant increase in the relative expression of 38 proteins (>2.0-folds, P < 0.05), while the relative expression of 34 proteins significantly decreased (<−2.0-folds, P < 0.05). The amoxicillin-resistant descendent strain exhibited marked alterations in carbohydrate and amino acid metabolism. Moreover, certain components involving in membrane metabolism were activated. The differences in the proteomic profiles between the two strains might explain the enhanced stress resistance of the adapted bacteria.

Antibiotic Resistance in Lactic Acid Bacteria

“…The genus Lactobacillus is an excellent receptor for exogenous genes by conjugation, as demonstrated by Abriouel et al [45] for the conjugative pAMβ1 plasmid found in Lactobacillus plantarum that could be obtained from enterococci and streptococci. Lactobacillus are commonly susceptible to antibiotics, such as penicillins (ampicillin, oxacillin, and piperacillin), inhibitors of β-lactamase, and cephalosporins (cephalothin and cefuroxime, ceftriaxone and cefoxitin), but in recent years some authors have reported resistance to penicillin G in some strains of Lactobacillus rhamnosus, Lactobacillus reuteri, and Lactobacillus plantarum [45,56]. Other studies demonstrated that Lactobacillus rhamnosus is safe to use as a starter or probiotic culture, despite having resistance genes to vancomycin, as these resistance is encoded into the chromosome [45,48,54].…”

The local transcriptional regulators SacR1 and SacR2 act as repressors of fructooligosaccharides metabolism in Lactobacillus plantarum

“…1). We assumed that the presence of glucose might induce global regulation [30,31], which would mask the effect of local regulation [32]. To investigate whether SacR1 and SacR2 play regulatory roles, we selected a nonrapidly utilized sugar-ribose as a carbon source and studied the differential expression of relevant genes in comparison with growth on FOS alone through an RT-qPCR analysis.…”

“…These deletion plasmids were transfected into L. plantarum ST-III cells via electroporation, and deletion mutants were screened as described previously [12,32]. Candidate double-crossover clones were confirmed by PCR analysis.…”

The local transcriptional regulators SacR1 and SacR2 act as repressors of fructooligosaccharides metabolism in Lactobacillus plantarum

“…1). We assumed that the presence of glucose might induce global regulation [30,31], which would mask the effect of local regulation [32].…”

“…The resultant DNA fragments were cloned into the suicide vector pNZ5319 to yield the pNZ5319-up-down-1 and pNZ5319-up-down-2 plasmid constructs. These deletion plasmids were transfected into L. plantarum ST-III cells via electroporation, and deletion mutants were screened as described previously [12,32]. Candidate double-crossover clones were con rmed by PCR analysis.…”