Study On The Microbial Diversity In The Intestine Of Gampsocleis Gratiosa

There are a lot of microorganisms in the intestines of insects,and the richness greatly depending on the host species.The microbial colonization of most insects has not been well studied,and there are still some researching spaces on that.Gampsocleis gratiosa belongs to the Tettigoniidae,Orthoptera.It is a good model organism for studying the growth and development of Orthoptera insects,the study has representative meanings for the incomplete metamorphosis or non-social insects.The main results are as follows:1?Based on the 450bp hypervariable sequence of V3-V4 in the 16S rDNA,we used Illumina MiseqTM high-throughput sequencing,analyzed the microbial composition of 1-7 instar nymphs and 4 stages of adults.We collected feces in a living state,and each group had 3 biological replicates,a total of 66 stool samples.207,913-248,223 sequences were sequenced from a single sample,finally,we had a total of 20.96 GB of raw data.2?We removed the barcode,primer and linker sequences,put the paired sequences together based on the overlap relationship between them.Then,according to the barcode tag before sequencing,each sample data can be separated from the fused data.Finally,we removed chimera and non-specific amplification sequences,obtained effective data after quality control.According to 97%similarity,a total of 576684 OTUs were obtained.3?At the level of phylum,class,order and family,the dominant species are relatively single,proportion of other flora is less than 1%.At the genus level,there are only six genus that exceeds 1%of the total quantity.We detected bacteria of 936 genus,251 family,112 order,78 class,and 44 phylum.Proteobacteria(57.62%)and Firmicutes(42.08%)in phylum level,Gammaproteobacteria(57.42%)and Bacilli(41.99%)in class level,Enterobacteriales(56.74%)and Lactobacillales(41.32%)in order level,Enterobacteriaceae(56.75%)and Lactobacillaceae(40.45%)in family level,Lactobacillus(40.37%),Hafnia(31.46%)and Kluyvera(15.79%)in genus level,are dominant.Composition of the gut microbes has differences at each developmental stages and between males and females.The dominant flora was basically consistent in each sample;however,the proportions varied greatly among the groups.The effects of different growth stages are larger than the differences caused by gender.4?The types of Gampsocleis gratiosa's gut microbes were relatively stable.The newly-bred nymphs contained a variety of bacteria in the feces,and basically had similar composition to the intestinal bacteria of their later ages.5?The colonized microbial community contributes greatly to the host's adaptation to the environment and growth.We can compare the microbes with the database through PICRUSt,and then link with biological functions to predict possible effects on host function.Based on COG,a total of 4791 genes were annotated,and 4352 were abundance.Based on KEGG,6908 genes were annotated and 5169 abundance.The basic composition is various enzymes,proteins,and regulatory factors.This proves that there is vertical transmission of microorganisms,larva eats the outer layer of the eggs to obtain the flora.The relationship between the evolutionary relationships of samples and their own characteristic is not significant.Considering Gampsocleis gratiosa is always kept under the same laboratory conditions,raised separately,and we set three biological replicates for each sample to ensures the accuracy of the results.Each sample is formed by the mixing from 6 individuals.Therefore,host plays a role in the intestinal microbial community,and may have the function of selecting a specific taxonomic group.The proportion of each intestinal microbe is related to the host development process and gender,indicating that the physiological changes in the host affect the growth of microorganisms.In addition to the dominant flora,many other types of bacteria have been discovered.However,the 44 phylum bacteria are concentrated in only two phylum.It shows that although the Gampsocleis gratiosa provides a variety of niches for the habitat of the flora,the intestinal environment also has strict limits on its survival.This results in a reduction of flora,only a small number of bacteria can adapt to life in the intestine,resulting in a reduction in the diversity of the intestinal flora,which is much smaller than the microbial diversity in the environment.Through prediction,we know that intestinal microbes involve a series of basic life functions that play a key role in the growth of Gampsocleis gratiosa,promoting development and metabolism.