Degradation Of Phenol By Fusarium Spp.QHM And BWC1 At Genomics And Transcriptomics Levels

In this study,two Fusarium strains were isolated from Qinghemen Coalminel water and Benxi Water Cave that were identified by building an evolutionary tree based on multi-gene method.Finally two strains were identified as Fusarium subglutinans?Fusarium sp.BWC1?and a member of Fusarium?Fusarium sp.QHM?.After genome sequencing on Illumina platform,bioinformatical analysis on genomics revealed that both of them had the potentiality of phenol declination.In addition,RNA sequencing on Fusarium sp.BWC1 under phenol stress at400mg/L concentration was performed by transcriptomical technique.By means of analyzing the differential expression and enrichment of different genes,the phenol degradation pathway was inferred,as well as the response of Fusarium subglutinans under phenol stress.The detailed results are as follows:?1?Two strains of Fusarium were genomically analyzed using DNA sequencing technology,and 14814 and 15295 genes of Fusarium spp.QHM and BWC1 were obtained.Genes of these two strains of fungi were categorized into six aspects by functional annotation.These two strains possessed the genes of xenobiotics degradation,such as phenol,as well as its complete phenol degradation pathway?KO00362?.?2?According to the biochemical analysis of phenol degradation,Fusarium spp.QHM and BWC1 achieved the optimal degradation at phenol concentration of 300 mg/L,and PDR?phenol degradation rate?were 43.65%and 39.91%,respectively between the concentration of 300?500mg/L.In the sewage simulation experiment,PDR was from 44.15%to 65.55%at phenol concentrations of 300 mg/L?700 mg/L and Fusarium sp.BWC1 had better degradability comparatively.Both Fusarium spp.QHM and BWC1 could degrade phenol under acidic or neutral conditions.?3?In transcriptome analysis,the following key genes of phenol metabolic pathway are up-regulated:phenol 2-monooxygenase?the initial metabolic catalytic enzyme??catechol1,2-dioxygenase?key enzyme??tricarboxylic acid cycle?acetyl Co A,malate dehydrogenase,citrate synthase,D-lactate dehydrogenase,succinate-semialdehyde dehydrogenase?.Accordingly,a conclusion was draw that the only metabolic pathway of phenol degradation under aerobic conditions by Fusarium subglutinans is:phenol?catechol?cis,cis-muconate?tricarboxylic acid cycle?H₂O+CO_2.?4?2050 differentially expressed genes were obtained through transcriptome analysis on Fusarium subglutinans.The genes that up-regulated in the process were found to be involved in chemotaxis,ABC transporters,pigments,heat shock proteins,stress response,efflux pump,and cellular stress response to oxidation by enrichment of differential genes.Furthermore,some activities in relation with the synthesis or metabolism of fatty acids,various amino acids and glycolysis of sugars were also strengthened as well.The results showed that under the stress of phenol,Fusarium subglutinans achieved degradation and tolerance to phenol by a positive response through genes regulation in advance.There are 27 figures,12 tables and 154 references in this paper.