Analysis of the differences in microbial community structures between suspended and sessile microorganisms in rivers based on quinone profile

摘要

In this study,a quinone profiling method was applied to calarify the differences in community strucure between suspended and sessile microorganisms in rivers.The compositions of microtial quinone of 6 sites for 4 rivers were anlayzed.Ubiquinone (UQ-8),UQ-10,menaquinone (MK)-7,and plastoquinone (PQ)-9 were observd in all samples of suspended and sessile microorganisms for the sites investigated.The dominant quinone species in suspended microorganisms was ubiquinone,and that in sessile microorganism was photosynthetic quinones(namely PQ-9 and vitamin K1).This indicatd that aerobic bacteria were abundant in the suspended microorganisms,and photosynthetic microorganisms such as micro-algae and cyanobacteria dominated in the sessile microorganisms.The quinone concentration in the river waers tested,which reflects the concentration of suspended microorganisms,ranged from 0.045 to 1.813 nmol/L.The microbial diversities of suspended and seesile microorganisms calculated based on the composition of all quinones were in the range from 3.4 to 7.5,which was lower than those for activated sludge and soils.Moreover,the diversity of heterotrophic bacteria for sessile microorgansims in the rivers was higher than that for the suspended microorganisms.