Chemotactic motility is involved in the virulence of many pathogenic bacteria. In order to understand the role of chemotactic motility of Vibrio harveyi in cellular processes and virulence, mini-TnlO/Kan transposon-in...Chemotactic motility is involved in the virulence of many pathogenic bacteria. In order to understand the role of chemotactic motility of Vibrio harveyi in cellular processes and virulence, mini-TnlO/Kan transposon-induced mutants with deficient chemotactic motility were constructed, screened, and iden- tified. Sequence analysis revealed that the 465-bp fragment （GenBank accession number HM630274） fank- ing the transposon insertion site in mutant TS-CM1 had the highest identity （96.9%） with a hypothetical protein gene of V. harveyiATCC BAA-1116 and the second-highest identity （91.8%） with the pgk gene of V. parahaemolyticus RIMD 2210633. In another mutant, TS-CM2, 356 bp of transposon-flanking sequence （GenBank accession number HM630275） also showed the highest identity （94.6%） with a hypothetical pro- tein gene of V. harveyi ATCC BAA-1116 and the second-highest identity （92.4%） with the flaB gene of V. alginolyticus HY9901. Studies on virulence-related biological characteristics such as growth, motility, adhe- sion, and infectivity of the mutants showed that disruption of either the flagellin gene or energy metabolism gene led to subsequent loss of chemotactic motility and changes in growth, motility, adhesion, and viru- lence of the pathogenic E harueyi. Hence, the flagellin gene and crucial energy metabolism gene played an important role in the chemotactic motility of V. harveyi.展开更多
To get a better understanding of the starvation survival strategy of pathogenic Vibrio alginolyticus, log-phase cells were inoculated into sterile natural seawater for starvation studies. The results showed that all o...To get a better understanding of the starvation survival strategy of pathogenic Vibrio alginolyticus, log-phase cells were inoculated into sterile natural seawater for starvation studies. The results showed that all of total bacteria number, viable bacteria number and CFU number of V. alginolyticus increased remarkably at the initial starvation stage; after reaching their peaks at 5 d, both total bacteria number and viable bacteria number of V. alginolyticus fell slowly, while the CFU number fell more quickly after reaching its peak at 10 d; V. alginolyticus elongated their cells at the prophase of starvation, and then shrunk their volume and turned their shapes into ovals from rods at the anaphase of starvation; starved cells showed more sensitivity to heating and UV; starved cells showed no significant difference from unstarved ones at the lowest detection limit determined by indirect enzyme-linked immu- nosorbent assay （ELISA） ; starved cells＇ ability to adhere to the skin mucus of large yellow croaker （ Pseudosciaena crocea） showed a sharp decline as the starvation time increases; the cellular protein of V. alginolyticus increased remarkably at the ariaphase of starvation. The results indicated that pathogenic V. alginolyticus could survive in starvation for relatively long periods of time （ ≥2 months） in 28℃ natural seawater due to the morphological and physiological changes; however, starved V. alginolyticus cells showed less virulence and higher sensitivity under environmental stresses.展开更多
基金The National Natural Science Foundation of China under contract Nos 31272699 and 41176115National Department Public Benefit Research Foundation of China under contract No. 200903029+1 种基金the Natural Science Foundation of Fujian Province under contract No.2011J06014the National Hi-Tech Research and Development Program of China (863 Program) under contract No. 2007AA09Z115
文摘Chemotactic motility is involved in the virulence of many pathogenic bacteria. In order to understand the role of chemotactic motility of Vibrio harveyi in cellular processes and virulence, mini-TnlO/Kan transposon-induced mutants with deficient chemotactic motility were constructed, screened, and iden- tified. Sequence analysis revealed that the 465-bp fragment （GenBank accession number HM630274） fank- ing the transposon insertion site in mutant TS-CM1 had the highest identity （96.9%） with a hypothetical protein gene of V. harveyiATCC BAA-1116 and the second-highest identity （91.8%） with the pgk gene of V. parahaemolyticus RIMD 2210633. In another mutant, TS-CM2, 356 bp of transposon-flanking sequence （GenBank accession number HM630275） also showed the highest identity （94.6%） with a hypothetical pro- tein gene of V. harveyi ATCC BAA-1116 and the second-highest identity （92.4%） with the flaB gene of V. alginolyticus HY9901. Studies on virulence-related biological characteristics such as growth, motility, adhe- sion, and infectivity of the mutants showed that disruption of either the flagellin gene or energy metabolism gene led to subsequent loss of chemotactic motility and changes in growth, motility, adhesion, and viru- lence of the pathogenic E harueyi. Hence, the flagellin gene and crucial energy metabolism gene played an important role in the chemotactic motility of V. harveyi.
基金The Hi-Tech Research and Development Program ("863"Program) of China under contract Nos 2001AA635070 and 2002AA639600the Natural Science Foundation of Fujian Province of China under contract No.B0410022
文摘To get a better understanding of the starvation survival strategy of pathogenic Vibrio alginolyticus, log-phase cells were inoculated into sterile natural seawater for starvation studies. The results showed that all of total bacteria number, viable bacteria number and CFU number of V. alginolyticus increased remarkably at the initial starvation stage; after reaching their peaks at 5 d, both total bacteria number and viable bacteria number of V. alginolyticus fell slowly, while the CFU number fell more quickly after reaching its peak at 10 d; V. alginolyticus elongated their cells at the prophase of starvation, and then shrunk their volume and turned their shapes into ovals from rods at the anaphase of starvation; starved cells showed more sensitivity to heating and UV; starved cells showed no significant difference from unstarved ones at the lowest detection limit determined by indirect enzyme-linked immu- nosorbent assay （ELISA） ; starved cells＇ ability to adhere to the skin mucus of large yellow croaker （ Pseudosciaena crocea） showed a sharp decline as the starvation time increases; the cellular protein of V. alginolyticus increased remarkably at the ariaphase of starvation. The results indicated that pathogenic V. alginolyticus could survive in starvation for relatively long periods of time （ ≥2 months） in 28℃ natural seawater due to the morphological and physiological changes; however, starved V. alginolyticus cells showed less virulence and higher sensitivity under environmental stresses.
