Assess The Characters Of Campylobacter Jejuni Under Non-ideal Conditions In Vitro

Objective:1.To observe the morphological change of Campylobacterjejuni under different conditions in Columbia agar and Brucella broth fordifferent time.2. To study the survival ability of Campylobacter jejuni underaerobic atmosphere in Columbia agar and Brucella broth.Methods:1. Recover Campylobacter jejuni strains stored in thelaboratory and culture them under micro-aerobic conditions at42℃,5%O₂，10%CO₂，85%N₂for24hours.2. Transfer and culture Campylobacter jejuniunder micro-aerobic condition and aerobic condition respectively.3.Campylobacter jejuni which was cultured under aerobic condition wasinoculated in new Columbia agar under micro-aerobic condition.4. Observethe morphological changes of Campylobacter jejuni which was cultured undermicro-aerobic condition or aerobic condition respectively for different time byusing Gram’s stain, scanning electron microscopes （SEM） and transmissionelectron microscopy （TEM）.5.Bacteria turbidity meter was utilized to test theturbidity of Campylobacter jejuni which was cultured under aerobic conditionfor different time.6. Identify Campylobacter jejuni strains, which was culturedunder different conditions by VITEK-2compact.Results:1.The spiral forms of Campylobacter jejuni which was culturedunder micro-aerobic condition for24hours was observed by SEM, and themorphology of Campylobacter jejuni changed when it was cultured underaerobic condition for10hours, which shortened, shriveled and liked a matchhead; the irregular coccid form of Campylobacter jejuni which was culturedunder aerobic condition for24hours was observed.2. Gram-negative coccoidform of Campylobacter jejuni which was cultured under micro-aerobiccondition for34hours was observed by Gram stain; but it was observed whenit was cultured under aerobic condition for14hours, with only a few Campylobacter jejuni remaining in a spiral form until84hours; Furthermore,we can observe very long bacteria.3.When the morphological changes inCampylobacter jejuni was inoculated in new Columbia agar undermicro-aerobic condition, it can still grow and revert to the spiral form.4. Thestructure of Campylobacter jejuni was observed by TEM. And whenCampylobacter jejuni was cultured under micro-aerobic condition for24hours,the structure was integrated, the density intracellular was uniform; but underaerobic condition for24hours, the structure was asymmetric, the densityintracellular was uneven with occasionally a spheroplast and ghost cells.5.Campylobacter jejuni which was cultured in Columbia agar under aerobiccondition for22days still can grow when it was inoculated in new Columbiaagar under micro-aerobic condition.6. Gram-negative bacilli was observedwhen Campylobacter jejuni was cultured in Brucella broth under differentconditions for different time. And Campylobacter jejuni which was cultured inBrucella broth under aerobic condition for20days still can grow when it wasinoculated in new Columbia agar under micro-aerobic condition, also it cangrow when it was inoculated in new Brucella broth under aerobic condition.7.Campylobacter jejuni which was cultured in Columbia agar undermicro-aerobic condition for24hours was identified as gram-negative bacilliby the gram staining, and then it was identified as Campylobacter jejuni byVITEK-2compact. But when Campylobacter jejuni cultured in Columbia agarunder aerobic condition for24hours was identified as Gram-negative cocci bythe gram staining, it was identified as Other bacteria by VITEK-2compact.Conclusions:1. The morphology of Campylobacter jejuni changed whenit was cultured under different conditions.2.The interior structure and enzymeof Campylobacter jejuni also changed when the morphology changed.3.Campylobacter jejuni was sensitive to environmental changes, and had astrong abilitiy to adapt to environmental changes.