混合培养对副溶血性弧菌致病株和非致病株生长的影响

Effects of mixed culture on the growth of pathogenic and nonpathogenic V.parahaemolyticus

以9∶1和1∶1的比例对致病性副溶血性弧菌(ATCC 33847:tdh+/trh-/tlh+;ATCC 17802:tdh-/trh+/tlh+)和非致病性副溶血性弧菌(G2:tdh-/trh-/tlh+;G8:tdh-/trh-/tlh+)在TSB培养基和熟虾中分别进行了混合和37℃10 h的混合培养,通过菌落原位杂交技术和PCR技术检测致病性菌株在混合培养前后的比例。结果显示,在TSB和熟虾中,致病菌比例均出现了下降。在熟虾样品中致病菌株下降的比例更高,其中ATCC17802和G8在熟虾样品中以9∶1比例混合并混合培养10 h后,致病菌比例从90%降为0。表明混合培养对致病性副溶血性弧菌菌株生长产生不利的影响,是造成水产样品中副溶血性弧菌感染频发却很难分离到致病性菌株的原因之一。

Pathogenic（ ATCC 33847： tdh ＋/trh-/tlh ＋; ATCC 17802： tdh-/trh ＋/tlh ＋） and nonpathogenic（ G2： tdh-/trh-/tlh ＋; G8： tdh-/trh-/tlh ＋） V. parahaemolyticuss strains were mixed at 9 ∶ 1and 1 ∶ 1 ratios and cultured at 37° C in tryptic soy broth（ TSB） or cooked shrimp for 10 h. The rate of isolation of the pathogenic strains after 10 h was determined by colony hybridization and PCR method,and the results showed that the isolation rate of the pathogenic strains decreased after co-culturing in TSB and cooked shrimp. The isolation rate of the pathogenic strains was more prominent in the shrimp samples,and when the strain ATCC 17802 was mixed with strain G8 in a 9∶ 1 ratio in the shrimp samples,no pathogenic strain was detected after 10 h. Negative effects of mixed culture on the growth of pathogenic V. parahaemolyticus are one of reasons for the rare isolation of V. parahaemolyticus from seafood samples.