Ecology Studies On Phosphonoacetate Degradation Bacterium In The South China Sea And The East China Sea

The South China Sea is a marginal sea of the western Pacific,and it has a vast maritime space and complex hydrological conditions.It is one kind of oligotrophic sea.The East China Sea is located in the estuary of the Yangtze River,and due to the influence of complementary terrestrial rivers and human activities,it is the highest productive sea in China.It is one kind of eutrophic sea.The organophosphate degradation microorganisms are the specific marine microorganisms which are able to degrade organophosphate.Depending on the ability of the degradation of organophosphate,these specific microorganisms offer the opportunity to reduce environmental pollution,add a phosphorus source for oligotrophic sea and provide nutrients for the marine microorganisms.Therefore,the organophosphate degradation microorganisms have become a hot research topic.Phosphonoacetate is one kind of synthetic phosphate,and it has been widely applied to the antiviral field.phnA is the particular gene which can regulate phosphonoacetate hydrolysis bacteria encoding the phosphonoacetate hydrolase.Moreover,phosphonoacetate hydrolase completes the hydrolysis of phosphonoacetate into acetate and inorganic phosphate.Consequently,the phosphonoacetate hydrolysis bacteria play a significant role in the ocean phosphorus cycle.The metabolic activity of phosphonoacetate hydrolysis bacteria require the participation of marine cellulose degradation microbial.Marine cellulose degradation microbial also participates in the ocean phosphorus cycle,and could supply the energy and phosphorus for the phosphonoacetate hydrolysis bacteria.Cellulose is the most widely distributed substance on earth.Its degradation is the core process to a natural carbon cycle.At the same time,due to closely related to the carbon cycle,based on influencing the concentration of CO2 in the atmosphere,the phosphorus cycle affects the global climate.In order to verify the diversity of the phnA gene of the South China Sea and the East China Sea,this research investigated the phosphonoacetate hydrolysis bacterial diversity,abundance,spatial distribution and community structure using phnA genes as molecular markers.The strain D-2 that was successfully isolated from the tideland soil of the East China Sea was able to degrade cellulose and hypophosphite compounds.The physiological and biochemical characteristics of the strain were studied in this research.The phnA gene sequences were obtained from the sediment of the South China Sea and the East China Sea.The phnA gene copies numbers were abundant as high as 103~108 copies in per gram sediment.The phosphonoacetate hydrolysis bacteria present uneven distribution by PCoA analysis and Jackknife Cluster analysis.Cr,As,Al,Mn,C/N,inorganic phosphorus,sorting coefficient,temperature and sediment silt content on the distribution patterns and abundance of the phosphonoacetate hydrolysis bacteria.The Strain D-2 that was isolated from the tideland soil of the East China Sea was able to degrade cellulose and hypophosphite compounds.The strain D-2 whose diameter was 0.5?m×1~3?m,in generally,came out individually or in two to four cells.The optimal conditions for the strain D-2's growth were 37?,pH 7.0 and with 20g·L-1 NaCl with Yeast Extract.Sequence analysis indicated that the percentage of similarity between 16 S rRNA genes of strain D-2 and Bacteroides reticulotermitis JCM 10512 T is 99%.Diversity,abundance and distribution of phosphonoacetate hydrolysis bacteria illustrated that the process of phosphonoacetate hydrolysis bacteria was closely linked with the marine P cycle in the South China Sea and the East China Sea.The strain D-2 that was isolated from the tideland soil of the East China Sea demonstrated the existence of the pathway that cellulose degradation bacteria metabolizes phosphorus compounds.Furthermore,this result certifies that the process of phosphorus degradation also existed in marine anaerobic conditions.