The objective of this study was to verify the supposition that efflux might be involved in the drug resistance of Riemerella anatipestifer isolates. Two broad-spectrum effiux pump inhibitors, carbonyl cyanide 3-chloro...The objective of this study was to verify the supposition that efflux might be involved in the drug resistance of Riemerella anatipestifer isolates. Two broad-spectrum effiux pump inhibitors, carbonyl cyanide 3-chlorophenylhydrazone （CCCP） and Phe-Arg-β-naphthylamide （PAL3N）, on the contribution of minimum inhibitory concentrations of amikacin, streptomycin, chloramphenicol, tetracycline, ceftdaxone, ceftazidime, nalidixic acid, levofloxacin, enrofloxacin, as well as ciprofloxacin against 69 clinical R. anatipestifer isolates were investigated. We first reported that the two efflux pump inhibitors could restore the antimicrobial susceptibility of R. anatipestiferisolates. It is suggested that active efflux system is possible to be linked with the development of resistance in R. anatipestifer isolates.展开更多
A small armed dinoflagellate bloomed in the aquaculture ponds off the coast of Liaodong Bay, Bohai Sea of China, resulting in heavy mortalities of the cultured prawns （Penaeusjaponicus） and larvae of Chinese mitten ...A small armed dinoflagellate bloomed in the aquaculture ponds off the coast of Liaodong Bay, Bohai Sea of China, resulting in heavy mortalities of the cultured prawns （Penaeusjaponicus） and larvae of Chinese mitten handed crabs （Eriocheir sinensis）. The bloom-forming species was successfully isolated, and cellular morphology of the specimen was consequently investigated through light, fluorescent and electron microscopy. The small （（14.4±1.6） μm in length） ellipsoid cells show typical Heterocapsa thecal plate arrangement （Po, cp, 5′, 3a, 7″, 6c, 5s, 5′″, 2″″）. The episome is evidently bigger than the hyposome. One to three spherical pyrenoids are located above or beside the large elongated nucleus. The body scale is characterized by a triangle basal plate with one central upright and nine peripheral spines. Above all, Heterocapsa bohaiensis could be distinguished from other Heterocapsa species by the combination of the cell size, morphology, cellular structure and body scale. Sequence analyses of both ITS and LSU regions reveal the significant genetic divergence between H. bohaiensis and other established species in this genus, further supporting novelty of this species. Noticeably, different sample treatment methods resulted in morphological variation of the apical pore complex （APC） of H. bohaiensis, which needs to be taken into account in future study.展开更多
基金supported by the Program for Changjiang Scholars and Innovative Research Team in University of Ministry of Education of China (IRT13063)the National Natural Science Foundation of China (31072169)
文摘The objective of this study was to verify the supposition that efflux might be involved in the drug resistance of Riemerella anatipestifer isolates. Two broad-spectrum effiux pump inhibitors, carbonyl cyanide 3-chlorophenylhydrazone （CCCP） and Phe-Arg-β-naphthylamide （PAL3N）, on the contribution of minimum inhibitory concentrations of amikacin, streptomycin, chloramphenicol, tetracycline, ceftdaxone, ceftazidime, nalidixic acid, levofloxacin, enrofloxacin, as well as ciprofloxacin against 69 clinical R. anatipestifer isolates were investigated. We first reported that the two efflux pump inhibitors could restore the antimicrobial susceptibility of R. anatipestiferisolates. It is suggested that active efflux system is possible to be linked with the development of resistance in R. anatipestifer isolates.
基金The NSFC-Shandong Joint Funded Project under contract No.U1406403the National Natural Science Foundation of China under contract Nos 41506191 and 41306171
文摘A small armed dinoflagellate bloomed in the aquaculture ponds off the coast of Liaodong Bay, Bohai Sea of China, resulting in heavy mortalities of the cultured prawns （Penaeusjaponicus） and larvae of Chinese mitten handed crabs （Eriocheir sinensis）. The bloom-forming species was successfully isolated, and cellular morphology of the specimen was consequently investigated through light, fluorescent and electron microscopy. The small （（14.4±1.6） μm in length） ellipsoid cells show typical Heterocapsa thecal plate arrangement （Po, cp, 5′, 3a, 7″, 6c, 5s, 5′″, 2″″）. The episome is evidently bigger than the hyposome. One to three spherical pyrenoids are located above or beside the large elongated nucleus. The body scale is characterized by a triangle basal plate with one central upright and nine peripheral spines. Above all, Heterocapsa bohaiensis could be distinguished from other Heterocapsa species by the combination of the cell size, morphology, cellular structure and body scale. Sequence analyses of both ITS and LSU regions reveal the significant genetic divergence between H. bohaiensis and other established species in this genus, further supporting novelty of this species. Noticeably, different sample treatment methods resulted in morphological variation of the apical pore complex （APC） of H. bohaiensis, which needs to be taken into account in future study.
