Diversity And Spatial Variability Of Ammonia Oxidizing Bacteria Based On Mothur And ArcGIS

Chemolithoautotrophic ammonium oxidation bacteria (Ammonia-oxidizing bacteria, AOB) is a kind of important function microorganisms, which catalyses the oxidation of ammonia to hydroxylamine by ammonia monooxygenase (AMO) and is biocatalysts on the first and limiting step of the nitrification process. In recent years, due to low maximum growth rates and difficult cultivation of AOB, most of the research about AOB depends on molecular technology. With developing of sequencing technology, which lead to both less expensive and largely automated, most AOB gene sequences have been sequenced. However, as sequencing capacity of Genbank explosible increases, how to analysis data effectivec and combine environmental factors together, has become a hot topic.In this paper, we analysted richness, diversity, Community structure and spatial variation of AOB respectively in China and global scope of conventional environment. We get16and37gene libraries respectively from China(administrative districts) and the world(5°×5°), discussed the relationship between AOB and environmental factors (temperature, longitude, latitude), trying to get the spatial variability of AOB through the new view.According to the data results of the analysis, we have the following conclusions:First, OTUs type of amoA is abundant in China, and there is246OTUs totally. Among them,87OTUs contains only a clone, and the majority dominant of OTU has242clone, accession number is EU624814, which has the highest similarity value with Nitrosospira sp. Nspl2(AY123823,AY298716) at99%. Furthermore, the OTUs number base on nucleotides sequence is more than those base on amino acid sequence,which demonstrating that some differences in the nucleotide sequences do not translate into differences in the protein sequences (synonymous changes). We also found that AOB sequences of adjacent region have certain of similarity through the Mothur software and HeNan, though they close to each other. Libshuff validation of16libraries has difference, and the results show that most of the libraries has significant differences, and part of the libraries with a certain distance also shows a similarity, that means there are other factors played a role on the diversity of the AOB except regional differences.Second, chaol value of15AOB libraries has a gradient descent from47.1to8with ArcGIS geostatistic analysis. AOB in sOTUhern and central regions of China has a higher adundance than northern and western region. The Shannon diversity index has gradually reduced from2.976to1.408. Base on analysis of China’s nearly50years average temperature contour, we found that high temperature area (>10℃) has a higher abundance and diversity, and in the low temperature region (<5℃, expect HuBei), the richness and diversity are lower. In local coastal cities, there also has lower diversity, it indicate that the diversity and abundance of AOB is not only affected by temperature of earth but also affected by other factors such as temperature of air, pH and so on. The spatial distribution of AOB also has different in diverse regional.Third, the diversity of amoA and16S rRNA gene of AOB in the world is analysed by Mothur. There is477OTUs with amoA(label=0.05), the most dominant OTU is EU624820, which has the highest similarity with Nitrosospira sp. NspⅢ7(AY123809) with value99%; For16S rRNA, there is159OTUs (label=0.05), the most dominant OTU is Z69162, which has the highest similarity with Nitrosospira sp. NspⅢ7(AY123809) with value99%. Visualized analysis of AOB shows that there is similar community composition and structure in some library, such as D (37°N,107°E) and E (37°N,112°E). But in others library, there is not consistency among them, such as library X (22°N,117°E) and N (320N,137°E). The geographical position is a impotant factor which effect on community structure and composition of AOB. According to result of Libshuff analyzes to37collections, there is significant differences between each other library.Fourth, for global37libraries analysis shows that the shannon index of AOB is gradient change along the longitude. The index value gradually reduced from138°E to80°W, and increasesd from80°W to123°W. We conclude that the diversity of AOB is influence by various factors and which account for area abnormalities. Shannon index contour is drawing base on Kriging interpolation method, which show shannon index gradient change from the3.464to0.371. The spatial distribution of AOB has obviously regional, and the diversity of AOB is influence by salinity and the Output of human life fertilization and high concentration of organic pollutants such as ammonia on some level.