title: Differential expression of virulence and stress fitness genes during interaction between Listeria monocytogenes and Bifidobacterium longum.
abstract: Bifidobacterium is well known to have an inhibitory effect on the survival, growth, and proliferation of various foodborne pathogens, but the mechanism of the molecular action of B. longum in blocking the invasion of Listeria monocytogenes is not yet well defined. In the present study, following RNA extraction and cDNA synthesis, differential expression of virulence and stress fitness genes in L. monocytogenes and B. longum was determined by real-time PCR. The results indicate that L. monocytogenes virulence factors, including actA, hly, inlA, and plcA, showed significantly downregulated expression during co-incubation of B. longum and L. monocytogenes in phosphate-buffered saline. The relative mRNA levels of oppA and serpin, two stress fitness genes in B. longum, were significantly higher than for the control group. These results indicate that downregulation of L. monocytogenes virulence factors during co-incubation with B. longum might be responsible for the inhibitory effects.
authors.affiliation: State Key Laboratory of Food Science and Technology, Nanchang University, Nanchang, China.
authors.forename: Qianglai
authors.initials: Q
authors.lastname: Tan
authors.forename: Hengyi
authors.initials: H
authors.lastname: Xu
authors.forename: Tingtao
authors.initials: T
authors.lastname: Chen
authors.forename: Peng
authors.initials: P
authors.lastname: Li
authors.forename: Zoraida P
authors.initials: ZP
authors.lastname: Aguilar
authors.forename: Di
authors.initials: D
authors.lastname: Xu
authors.forename: Xing
authors.initials: X
authors.lastname: Ming
authors.forename: Feng
authors.initials: F
authors.lastname: Xu
authors.forename: Hua
authors.initials: H
authors.lastname: Wei
mesh_terms: D000898:Antibiosis; D058491:Bacterial Load; D001426:Bacterial Proteins / Q000235:genetics* / Q000378:metabolism; D001644:Bifidobacterium / Q000235:genetics* / Q000254:growth & development; D003470:Culture Media; D004269:DNA, Bacterial / Q000235:genetics*; D018076:DNA, Complementary / Q000032:analysis; D020869:Gene Expression Profiling; D015964:Gene Expression Regulation, Bacterial; D008089:Listeria monocytogenes / Q000235:genetics* / Q000254:growth & development / Q000472:pathogenicity; D050296:Microbial Viability; D012333:RNA, Messenger / Q000096:biosynthesis*; D060888:Real-Time Polymerase Chain Reaction; D013312:Stress, Physiological / Q000235:genetics; D014774:Virulence / Q000235:genetics; D037521:Virulence Factors / Q000235:genetics* / Q000378:metabolism
chemical_list: D001426:Bacterial Proteins; D003470:Culture Media; D004269:DNA, Bacterial; D018076:DNA, Complementary; D012333:RNA, Messenger; D037521:Virulence Factors