细菌性阴道病肠道菌群与阴道菌群16S rDNA测序分析

目的通过对细菌性阴道病(BV)患者肠道菌群及阴道菌群16S rDNA扩增子测序,分析其结构、多样性、相关性以及BV对肠道菌群的影响,为今后治疗BV提供新的思路。方法选取符合纳入标准的BV患者11例(BV组),健康者9例(C组),留存阴道分泌物及新鲜粪便进行16S rDNA基因检测分析。结果C组阴道菌群以乳杆菌属为主,BV与加德纳菌属、普雷沃菌属、Sneathia、窄食单胞菌属(Stenotrophomonas)、阿托波菌属、Shuttleworthia、巨型球菌属密切相关。BV组肠道、阴道菌群丰富度均高于C组。Alpha多样性分析中C组和BV组肠道菌群、阴道菌群的Shannon指数组间比较,χ²值为29.137, P=0.000<0.05,两组阴道菌群Shannon指数组间比较差异具有统计学意义(P<0.05),BV组高于C组。物种多样性曲线反映本研究样本测序数据量的合理性,表明BV组的肠道菌群多样性、丰富度均高于C组,主坐标分析表明C组肠道与阴道的菌群结构差距较大,BV组肠道与阴道的菌群结构有相似之处,且两组肠道菌群结构接近。BV组阴道菌群中厚壁菌门丰度较C组低,放线菌门、拟杆菌门较C组高;BV组肠道菌群中拟杆菌门丰度较C组低;C组肠道中拟杆菌门明显高于阴道,厚壁菌门明显低于阴道; BV组阴道菌群中放线菌门丰度高于C组,差异均具有统计学意义(P<0.05)。结论BV阴道菌群与肠道菌群具有相关性,BV可能引起肠道菌群结构比例和多样性的改变。     

赫哲族和汉族健康人群肠道细菌群落分析

目的 对汉族和赫哲族健康人群肠道菌群进行研究,探讨遗传背景和饮食习惯对肠道菌群多样性以及组成的影响.方法 以佳木斯市区20例健康汉族人群、佳木斯街津口赫哲族聚居地的20例健康赫哲族志愿者及20例健康汉族人群粪便样本为研究对象,应用基于16S rDNA V3-V4可变区的高通量测序技术测定肠道菌群多样性以及核心菌群的组成...     

山西省东南部地区胃癌患者肠道菌群分布的配对病例对照研究

目的 观察胃癌患者肠道菌群的变化,为研究其发病机制和治疗措施提供依据.方法 按照1∶1配对原则(年龄、性别、民族、居住地等)在长治某医院根据胃镜检查结果分别选取尚未进行过治疗的10例胃癌患者(胃癌组)和10例健康人群(对照组),面对面调查填写基本信息表,留取粪便样本,采用微生物16S rDNA扩增子测定技术检测粪便菌群...     

家蚕肠道产蛋白酶细菌的分离筛选与分子鉴定

目的肠道细菌对家蚕具有重要的生理作用,探明家蚕肠道产蛋白酶细菌菌群对家蚕肠道细菌的高效开发与利用具有十分重要的意义。方法从菁松×皓月品种4龄家蚕肠液中分离与纯化肠道细菌,获得一株产高活力蛋白酶细菌,对该菌菌落进行形态学鉴定及菌体的显微镜检并结合16S rDNA方法进行了鉴定。结果该菌为革兰阴性杆菌,属于嗜麦芽寡养单胞菌(Stenotrophom onas maltophilia)。结论该产蛋白酶细菌产酶能力较高,可进一步开发研究并用作微生态制剂。     

Quantitative analysis of the intestinal bacterial community in one- to three-week-old commercially reared broiler chickens fed conventional or antibiotic-free vegetable-based diets

AIMS: To explore the effect of drug-free poultry production on the intestinal microflora of broiler chickens, the bacterial community of this environment was quantitatively profiled in both conventionally reared birds and birds reared without antibiotic growth promotants (AGPs) on a vegetable-based diet. METHODS AND RESULTS: Quantitative, real-time PCR with group-specific 16S rDNA primer sets was used to enumerate the abundance of the following chicken gastrointestinal (GI) tract phylogenetic groups: the Clostridium leptum-Faecalibacterium prausnitzii subgroup (Clostridium genus cluster IV), the Clostridium coccoides - Eubacterium rectale subgroup (Clostridium cluster XIVa and XIVb), the Bacteroides group (including Prevotella and Porphyromonas), Bifidobacterium spp., the Enterobacteriaceae, the Lactobacillus group (including the genera Leuconostoc, Pediococcus, Aerococcus and Weissella), the Clostridium perfringens subgroup (Clostridium cluster I), Enterococcus spp., Veillonella spp., Atopobium spp., Campylobacter spp. and the domain Bacteria. A species-specific 5'-nuclease (Taqman) assay was also employed to specifically assess Cl. perfringens abundance. Ten birds were sampled from each of two commercial chicken houses, one in which feed was supplemented with AGPs and exogenous animal protein, and the other vegetable-based and drug-free, at 7, 14 and 21 days of age. The ileal community was dominated by two large populations, the lactobacilli and the Enterobacteriaceae, with those taxa much more numerous in drug-free vegetable-based diet fed birds than those conventionally reared at the 7- and 14-day time periods. The progressive changes in microflora in both the conventional and drug-free caeca were similar to each other, with the Enterobacteriaceae sequences dominating at day 7, but being replaced by obligate anaerobe signature sequences by day 14. Of note was the finding that all the day 14 and day 21 replicate caecal samples from the drug-free house were positive for Campylobacter spp. averaging >10(8) 16S rDNA gene copies per gram wet weight. CONCLUSIONS: Quantitative, real-time PCR indicates that the effects of drug-free rearing on the chicken GI tract microbial community are most pronounced in the ileal region, but AGPs may be important in controlling Campylobacter colonization of the caecum. SIGNIFICANCE AND IMPACT OF THE STUDY: A quantitative taxonomic understanding of the shifting microbial ecology of the broiler chicken gut microbiota is important in the light of AGP withdrawal. AGP withdrawal has occurred in response to concerns over the transfer of antimicrobial-resistant bacteria to humans via the food production chain.     

乙型肝炎肝硬化腹水合并自发性细菌性腹膜炎患者肠道菌群特征

初步分析乙型肝炎肝硬化腹水合并自发性细菌性腹膜炎（SBP）患者肠道菌群特征,为该类患者的治疗提供参考。

选取我院符合纳入标准的乙型肝炎肝硬化腹水患者45例为研究对象,其中24例合并SBP的患者为SBP组、21例未合并SBP的患者为NSBP组,另选同期20例健康人为HC组。应用16S rDNA测序技术检测患者肠道菌群,并使用生物信息学方法分析各组对象肠道菌群变化。

SBP组、NSBP组及HC组相比,其肠道菌群的物种多样性及丰富度差异均无统计学意义（均P＜0.05）。PCoA分析显示,NSBP组与HC组患者肠道菌群结构相似,SBP组与其他两组相比菌群结构较为不同。与NSBP组相比,SBP组患者肠道菌群中变形菌门（Proteobacteria,5.45% vs 13.50%,U = 161.000,P = 0.038）、软壁菌门（Tenericutes,0.019% vs 0.073%,U = 162.000,P = 0.035）、埃希—志贺菌属（Escherichia-Shigella,0.24% vs 9.53%,U = 103.000,P = 0.001）、柠檬酸杆菌属（Citrobacter,LDA＞2）等丰度均增加;酸杆菌门（Acidobacteria,0.026% vs 0.015%,U = 152.000,P = 0.023）、罗氏菌属（Roseburia,2.55% vs 2.00%,U = 152.000,P = 0.023）、粪球菌属（Coprococcus,LDA＞2）等丰度下降。

乙型肝炎肝硬化腹水的发生发展与肠道菌群密切相关,在SBP患者肠道菌群中发现潜在病原体数量显著增加,并伴随有益细菌数量的减少。

     

Bacteria abundance and diversity of different life stages of Plutella xylostella (Lepidoptera: Plutellidae), revealed by bacteria culture‐dependent and PCR‐DGGE methods

Microbial abundance and diversity of different life stages (fourth instar larvae, pupae and adults) of the diamondback moth, Plutella xylostella L., collected from field and reared in laboratory, were investigated using bacteria culture‐dependent method and PCR‐DGGE analysis based on the sequence of bacteria 16S rRNA V3 region gene. A large quantity of bacteria was found in all life stages of P. xylostella. Field population had higher quantity of bacteria than laboratory population, and larval gut had higher quantity than pupae and adults. Culturable bacteria differed in different life stages of P. xylostella. Twenty‐five different bacterial strains were identified in total, among them 20 strains were presented in larval gut, only 8 strains in pupae and 14 strains in adults were detected. Firmicutes bacteria, Bacillus sp., were the most dominant species in every life stage. 15 distinct bands were obtained from DGGE electrophoresis gel. The sequences blasted in GenBank database showed these bacteria belonged to six different genera. Phylogenetic analysis showed the sequences of the bacteria belonged to the Actinobacteri, Proteobacteria and Firmicutes. Serratia sp. in Proteobacteria was the most abundant species in larval gut. In pupae, unculturable bacteria were the most dominant species, and unculturable bacteria and Serratia sp. were the most dominant species in adults. Our study suggested that a combination of molecular and traditional culturing methods can be effectively used to analyze and to determine the diversity of gut microflora. These known bacteria may play important roles in development of P. xylostella.     

Molecular Phylogenetic Analysis of Archaea and Bacteria in Wind Cave,South Dakota

The diversity of bacteria and archaea was characterized from sediments collected from Wind Cave located in Wind Cave National Park in the Black Hills of South Dakota. Wind Cave is a limestone dissolution cave with strata that started forming over 300 million years ago, making it one of the oldest in the world. Previous work suggested that the cave was largely a detritus based system ultimately dependent upon allochthonous energy and carbon from photosynthesis of the overlying vegetation, and algae growing near lights along the tour routes. In this work, we used a molecular phylogenetic approach to characterize the microbial structure and infer a corresponding ecosystem function where appropriate. Four bacterial divisions and subdivisions were found in the culture collection, which represented 14 phylotypes, whereas 12 divisions and subdivisions were identified in the clonal analysis comprising 49 phylotypes. The predominant groups were the γ-Proteobacteria and Acidobacteria. Although a few of the clones resembled sequences from other cave and subterranean systems, no cave-specific bacterial community was evident in this work. Archaeal phylotypes (20 Crenarchaeota and 2 Euryarchaeota) were detected, with a large proportion of the Crenarchaeota resembling sequences from a South African gold mine. One archaeal cluster in particular appears to be specific to the subterranean environment. Most of the microbial sequences were not related to known chemolithoautotrophs, therefore we conclude that this particular community is likely detritus based where allochthonous energy and carbon are transported into the cave by infiltrating waters.     

基于16S rDNA测序技术分析功能性便秘患者粪便菌群

运用16S rDNA测序技术分析功能性便秘（FC）患者粪便菌群特征,以期寻找FC特征菌,为FC诊治寻找新的治疗靶点。

收集福建中医药大学附属第二人民医院60例实验组（FC患者）和30例正常组的粪便,采用16S rDNA测序技术分析粪便菌群结构,并进行基因功能的预测。

两组在门水平上,主要由厚壁菌门和拟杆菌门组成;在属水平上,主要优势菌以粪杆菌属和拟杆菌属为主。实验组粪便菌群丰富度指数Chao1、Observed_OTUs较正常组升高（P＜0.05）,多样性指数Shannon指数和Simpson指数虽有上升趋势,但差异无统计学意义（P＞0.05）。布劳特菌属、罗氏菌属、Ruminococcus_gnavus_group、Ruminococcus_gauvreauii_group、Eubacterium_hallii_group、Anaerostipes、Lachnospiraceae_ND3007_group、Dorea、乳球菌属在实验组中丰度均显著降低（P＜0.01）。实验组特征菌为小杆菌属,正常组为布劳特菌属和埃希菌−志贺菌属。实验组蔗糖降解Ⅲ（PWY-621）、丙酮酸发酵成乙酸和乳酸（PWY-5100）和琥珀酸发酵成丁酸盐（PWY-5677）功能下降（P＜0.05）。

功能性便秘患者主要表现为肠道菌群丰度与多样性升高,FC的发病可能与菌群结构发生改变有关。

     

Characterization of benthic bacterial assemblages in a polluted stream using denaturing gradient gel electrophoresis

To study differences in bacterial assemblages among sites with different environmental conditions, sediment samples were collected from three sites along a South Carolina (U.S.A.) coastalplain stream with varying levels of anthropogenic perturbation. The objective of this study was to compare the bacterial assemblages among these sites to detect possible impacts from the disturbance. To accomplish this comparison, DNA was extracted from the samples and subjected to the polymerase chain reaction using primers designed to amplify bacterial 16S rRNA genes. Relative measures of bacterial genetic diversity, assessed using denaturing gradient gel electrophoresis (DGGE), revealed greater numbers of unique sequences at the disturbed sites. The number of bands, which is analogous to species richness, did not vary predictably among sites. Similarity indices revealed a high level of similarity among replicate samples from each site and low similarity between samples from different sites. This study demonstrated that bacterial assemblages differed among sites and that the presence or absence of certain species, represented by unique DGGE bands, differed among sites; unique bands were most commonly encountered at the disturbed sites. Based on the evidence gathered, we conclude that benthic bacterial assemblages vary longitudinally and that anthropogenic disturbance may alter the bacterial component of streams.     

植物叶际固氮菌研究进展

固氮菌广泛存在于植物叶际,能固定空气中的氮气,满足自身或植物的部分氮素需求。基于纯种分离和培养的传统生物学方法已经研究了部分叶际固氮菌的特性,但对叶际固氮菌的物种组成、群落结构及生态功能等方面的认识还非常有限。随着分子生物学技术的发展、微生物分子生态学研究方法的逐步成熟,人们对叶际微生物的多样性和生态功能的研究越来越深入。叶际固氮菌具有丰富的多样性,温度、湿度、光照等环境因素及植物种类和微生物互作均会影响叶际固氮菌的组成。不同于根际固氮菌,叶际固氮菌具有非专一性,且不易受化肥的影响,其在农业生产上已经表现出潜在的应用价值。为此,本文综述了农作物、森林、海域生态系统中叶际固氮菌的群落结构组成及生态功能,以及外界因素对叶际固氮系统的影响。     

Bacterial diversity associated with the Brazilian endemic reef coral Mussismilia braziliensis

Aims:  We performed the first characterization of the microbiota associated with the reef coral Mussismilia braziliensis by means of a culture-independent approach.
Methods and Results:  The main groups were Proteobacteria , Cyanobacteria and unclassified bacteria according to the 16S rDNA libraries. Most of the sequences of the mucus of healthy and diseased M. braziliensis did not find close matches in GenBank (i.e. >97% 16S rDNA similarity). Most of the sequences of seawater and mucus of healthy coral fell into tight clusters (17 and 15 clusters respectively). In contrast, most of the sequences of mucus of diseased coral did not form clusters. The rarefaction curves indicate saturation in the recovery of higher taxa (approximately 40 phyla). However, the number of species in the coral mucus ( n  = 130–170) and seawater ( n  = 170) did not reach a plateau.
Conclusions:  The coral microbiota encompasses several potentially novel species and higher taxa. The microbiota of M. braziliensis appears to be species-specific. Diseased coral may have provided a suitable place for colonization by opportunistic bacteria, resulting in a greater bacterial diversity.
Significance and Impact of the Study:  The first study on the diversity of the microbiota of the endemic and endangered of extinction coral M. braziliensis .     

四磨汤对脾虚便秘小鼠肠道细菌丰度及功能基因的影响

目的 探讨四磨汤对脾虚便秘小鼠肠道细菌丰度及功能基因的影响,为其疗效机制提供依据。方法 采用番泻叶泄泻、饥饱失常和控制饮食等复合因素建立小鼠脾虚便秘模型,造模成功后,治疗组小鼠分别用四磨汤和枳术汤灌胃,模型组和正常组小鼠用无菌水灌胃。造模结束和治疗结束后分别提取小鼠肠道微生物总DNA,进行16S rDNA V4区测序。结果 脾虚便秘造模降低了小鼠肠道细菌丰度,四磨汤治疗后,小鼠肠道细菌丰度整体水平上与模型组比较差异不显著。基于功能基因分析,造模降低了小鼠细胞信号传导、能量代谢、脂质代谢和一些辅酶、维生素代谢等的作用,提高了核苷酸代谢、碳水化合物代谢、氨基酸代谢和酶类等的水平。四磨汤口服液治疗后,小鼠的肠道细菌功能基因碳水化合物代谢、能量代谢、氨基酸代谢、核苷酸代谢、脂质代谢、多糖生物合成、遗传信息复制、翻译和跨膜运输等方面要显著高于其余各组。结论 脾虚便秘小鼠降低了肠道细菌能量、糖类和脂质代谢,四磨汤可能通过提高肠道细菌能量和营养物质的代谢,提高遗传信息的复制、转录、翻译和跨膜转运水平来达到治疗脾虚便秘的效果。基于功能基因的角度分析为小鼠肠道细菌的改变提供了依据。     

Identification of causative pathogens in mouse eyes with bacterial keratitis by sequence analysis of 16S rDNA libraries

The clone library method using PCR amplification of the 16S ribosomal RNA (rRNA) gene was used to identify pathogens from corneal scrapings of C57BL/6-corneal opacity (B6-Co) mice with bacterial keratitis. All 10 samples from the eyes with bacterial keratitis showed positive PCR results. All 10 samples from the normal cornea showed negative PCR results. In all 10 PCR-positive samples, the predominant and second most predominant species accounted for 20.9 to 40.6% and 14.7 to 26.1%, respectively, of each clone library. The predominant species were Staphylococcus lentus, Pseudomonas aeruginosa, and Staphylococcus epidermidis. The microbiota analysis detected a diverse group of microbiota in the eyes of B6-Co mice with bacterial keratitis and showed that the causative pathogens could be determined based on percentages of bacterial species in the clone libraries. The bacterial species detected in this study were mostly in accordance with results of studies on clinical bacterial keratitis in human eyes. Based on the results of our previous studies and this study, the B6-Co mouse should be considered a favorable model for studying bacterial keratitis.     

Impact of cultivation on characterisation of species composition of soil bacterial communities

The species composition of culturable bacteria in Scottish grassland soils was investigated using a combination of Biolog and 16S rDNA analysis for characterisation of isolates. The inclusion of a molecular approach allowed direct comparison of sequences from culturable bacteria with sequences obtained during analysis of DNA extracted directly from the same soil samples. Bacterial strains were isolated on Pseudomonas isolation agar (PIA), a selective medium, and on tryptone soya agar (TSA), a general laboratory medium. In total, 12 and 21 morphologically different bacterial cultures were isolated on PIA and TSA, respectively. Biolog and sequencing placed PIA isolates in the same taxonomic groups, the majority of cultures belonging to the Pseudomonas (sensu stricto) group. However, analysis of 16S rDNA sequences proved more efficient than Biolog for characterising TSA isolates due to limitations of the Microlog database for identifying environmental bacteria. In general, 16S rDNA sequences from TSA isolates showed high similarities to cultured species represented in sequence databases, although TSA-8 showed only 92.5% similarity to the nearest relative, Bacillus insolitus. In general, there was very little overlap between the culturable and uncultured bacterial communities, although two sequences, PIA-2 and TSA-13, showed >99% similarity to soil clones. A cloning step was included prior to sequence analysis of two isolates, TSA-5 and TSA-14, and analysis of several clones confirmed that these cultures comprised at least four and three sequence types, respectively. All isolate clones were most closely related to uncultured bacteria, with clone TSA-5.1 showing 99.8% similarity to a sequence amplified directly from the same soil sample. Interestingly, one clone, TSA-5.4, clustered within a novel group comprising only uncultured sequences. This group, which is associated with the novel, deep-branching Acidobacterium capsulatum lineage, also included clones isolated during direct analysis of the same soil and from a wide range of other sample types studied elsewhere. The study demonstrates the value of fine-scale molecular analysis for identification of laboratory isolates and indicates the culturability of approximately 1% of the total population but under a restricted range of media and cultivation conditions.     

Molecular phylogenetic profiling of gut‐associated bacteria in larvae and adults of flesh flies

Flesh flies of the genus Sarcophaga (Diptera: Sarcophagidae) are carrion‐breeding, necrophagous insects important in medical and veterinary entomology as potential transmitters of pathogens to humans and animals. Our aim was to analyse the diversity of gut‐associated bacteria in wild‐caught larvae and adult flesh flies using culture‐dependent and culture‐independent methods. Analysis of 16S rRNA gene sequences from cultured isolates and clone libraries revealed bacteria affiliated to Proteobacteria, Actinobacteria, Firmicutes and Bacteroidetes in the guts of larval and adult flesh flies. Bacteria cultured from larval and adult flesh fly guts belonged to the genera Acinetobacter, Bacillus, Budvicia, Citrobacter, Dermacoccus, Enterococcus, Ignatzschineria, Lysinibacillus, Myroides, Pasteurella, Proteus, Providencia and Staphylococcus. Phylogenetic analysis showed clone sequences of the genera Aeromonas, Bacillus, Bradyrhizobium, Citrobacter, Clostridium, Corynebacterium, Ignatzschineria, Klebsiella, Pantoea, Propionibacterium, Proteus, Providencia, Serratia, Sporosarcina, Weissella and Wohlfahrtiimonas. Species of clinically significant genera such as Ignatzschineria and Wohlfahrtiimonas spp. were detected in both larvae and adult flesh flies. Sequence analysis of 16S rRNA gene libraries supported culture‐based results and revealed the presence of additional bacterial taxa. This study determined the diversity of gut microbiota in flesh flies, which will bolster the ability to assess microbiological risk associated with the presence of these flies. The present data thereby establish a platform for a much larger study.     

Ugan古河道胡杨可培养内生细菌的多样性

摘要：【目的】为了了解塔河废弃古河道胡杨可培养内生细菌的多样性。【方法】从2棵胡杨树干部抽出其内存液,采用三种不同的培养基对样品的内生细菌进行了分离纯化;对它们进行16S rDNA测定和系统进化分析。【结果】分离纯化不同表型的细菌62株,对它们的16S rDNA序列分析表明,62株菌分别属于四个大类群;厚壁菌门（Firmicutes）、放线菌门(Actinobacteria)、α-变形菌纲(Alpha Proteobacteria) 、γ-变形菌纲(Gamma Proteobacteria),18个属,32个种;芽孢杆菌属和假单胞菌属是胡杨可培养内生细菌的优势细菌种群,它们分别占已测种群的40.32%、16.13%。其中菌株KTH-63为葡萄球菌科的潜在的新属新种,它与最近源菌株的16S rDNA序列相似率为92.491%;9株菌KLH-21、KLH-1、KTH-8、KTH-14、KNA-26、KLH-18、KTH-20、KNA-3、KLH-25是潜在的新种（16S rDNA相似率为96.089 %-97.769 %）,胡杨树干内存液中潜在新种的发现率高达总分离检测菌株的16.13 % 。本研究获得的胡杨可培养内生细菌的群落结构数据给植物内生细菌新增了10个属,18个种。【结论】胡杨具有多样性极其丰富的可培养内生细菌菌种资源,土著新种的发现频率超出了预期,胡杨可培养内生细菌的群落结构极大地刷新了植物内生细菌的种群记录,极具进一步发掘的潜力。     

Midgut bacterial communities in the giant Asian honeybee (Apis dorsata) across 4 developmental stages: A comparative study

Bacterial communities are known to play important roles during the developmental stages of insects, but current knowledge of bacteria associated with the midgut of Apis dorsata, the giant Asian honeybee, is limited. Using polymerase chain reaction‐denaturing gradient gel electrophoresis analysis (PCR‐DGGE) and 16S rRNA sequencing, the aim of this study was to determine the dynamics of bacterial community structure across four A. dorsata life stages in different geographical locations. The results reveal that bacterial diversity increased as the bee progressed through larval stage to newly emerged worker and old worker. However, in the pupal stage, no bands identified as bacteria could be observed. Overall, 2 bacterial phyla (Proteobacteria and Firmicutes) and 4 classes (Alphaproteobacteria, Betaproteobacteria, Gammaproteobacteria, and Bacilli) were identified, but the frequency varied among the different stages and locations. The classes of Gammaproteobacteria and Bacilli dominated among larval, newly emerged worker and old worker developmental stages.     

稻纵卷叶螟肠道细菌群落结构与多样性分析

【目的】为明确水稻主要害虫稻纵卷叶螟Cnaphalocrocis medinalis(Guenée)幼虫肠道细菌的群落结构和多样性。【方法】利用Illumina Mi Seq技术对稻纵卷叶螟4龄幼虫肠道细菌的16S r DNA V3-V4变异区序列进行测序,应用USEARCH和QIIME软件整理和统计样品序列数和操作分类单元(operational taxonomic unit,OTU)数量,分析4龄幼虫肠道细菌的物种组成、丰度和多样性。【结果】稻纵卷叶螟4个数量不同的4龄幼虫样本(1,2,3和5头)共得165 386条reads,在97%相似度下可将其聚类为604个OTUs。总共注释到22个门,43个纲,82个目,142个科,204个属,244个种。其中在门水平上,主要优势菌为变形菌门(Proteobacteria)(相对丰度26%~34%)和放线菌门(Actinobacteria)(23%~32%);在纲水平上,主要优势菌为放线菌纲(Actinobacteria)(相对丰度23%~32%)、酸杆菌纲(Acidobacteria)(9%~11%)、α-变形菌纲(Alphaproteobacteria)(10%~13%)、β-变形菌纲(Betaproteobacteria)(6%~8%)和γ-变形菌纲(Gammaproteobacteria)(6%~12%);在科水平上,共有优势菌为类诺卡氏菌科(Nocardioidaceae)、丛毛单胞菌科(Comamonadaceae)、黄单胞菌科(Xanthomonadaceae)、鞘脂单胞菌科(Sphingomonadaceae)和芽单胞菌科(Gemmatimonadaceae)等。在属水平上,4个样本前5位优势属中,类诺卡氏属Nocardioides和鞘脂单胞菌Sphingomonas为共有优势属。稻纵卷叶螟肠道细菌Simpson指数、Shannon指数、Ace指数和Chao指数分别为0.16~0.65,0.94~3.22,212~488和210~490。【结论】稻纵卷叶螟幼虫肠道细菌多样性比较丰富,个体间微生物群落结构和多样性有差异。不同数量样本数据与总体数据有助于综合反映稻纵卷叶螟种群肠道微生物状况。本研究结果为进一步研究稻纵卷叶螟肠道微生物的功能及其在防治中的应用奠定了基础。