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1.
【目的】了解马氏珠母贝(Pinctada fucata martensii)肠道及其养殖水体可培养细菌的群落组成。【方法】采用2216E平板涂布法研究海区养殖马氏珠母贝肠道与养殖水体的可培养菌群种类及丰度。【结果与结论】马氏珠母贝肠道及其养殖水体的可培养细菌归属于2门(变形菌门和厚壁菌门)3纲7目10科23属56种。属水平上,肠道中以弧菌属(74.7%)和假交替单胞菌属(18.7%)为主;养殖水体中α-变形菌纲的FJ943236_g属(40.7%)丰度最大,弧菌属(16.7%)相对肠道丰度较低。样品共有菌属为弧菌属、假交替单胞菌属、发光杆菌属和芽孢杆菌属;肠道特有菌属为希瓦氏菌属和盐单胞菌属;养殖水体特有菌属主要为FJ943236_g、鲁杰氏菌属和Nautella。在种水平上,7个种为二者共有;马氏珠母贝肠道和养殖水体特异性菌种分别为18个和31个。虽然门水平上马氏珠母贝肠道中可培养细菌群落与其养殖水体中的细菌群落大致相似,但在属、种水平上二者差异明显。 相似文献
2.
hacteria(SRB)canbeashighastenhmesthainseahattOInsetlimentwithouSRB.Theex-perimentsinsimulatingseahattmsedimentswithdifferentconcenhations0fcultUredSRBsh0WedthatheelecthehendcalpoariZaionbehavi0ur0fsteelinseahatt()msedimentwithandwithouSRBwerefferent.SRBalteredthepoarizationbehavi0ur0fsteelsignificanilbyaciopingtheenvironments0thaaP-parenthydrogendepoallzationoccurredandacceleratedthec0meionofsteel.Keywofor:anaerohe,seab0ttomsediment,steelINTRODUCTIONAnaerobesaregenerallypresentins… 相似文献
3.
EFFECT OF SULPHATE-REDUCING BACTERIA ON ELECTRO-CHEMICAL CORROSION BEHAVIOR OF 16Mn STEEL IN SEA MUD
ＩＮＴＲＯＤＵＣＴＩＯＮＩｔｗａｓｇｅｎｅｒａｌｌｙｃｏｎｓｉｄｅｒｅｄｐｒｅｖｉｏｕｓｌｙｔｈａｔｔｈｅｃｏｒｒｏｓｉｏｎｏｆｓｔｅｅｌｉｎｓｅａｍｕｄｗａｓｎｏｔｓｅｒｉｏｕｓ.Ｈｏｗｅｖｅｒ,ｉｔｗａｓｌａｔｅｒｆｏｕｎｄｔｈａｔｔｈｅｃｏｒｒｏｓｉｏｎｒａｔｅｏｆｓｔｅｅｌｉｎｓｏｍｅｓｅａｍｕｄｗａｓｈｉｇｈｅｒｔｈａｎｔｈａｔｉｎｓｅａｗａｔｅｒ(Ｋｉｎｇ,1980;Ｓｅｈｍｉｄｅ,1982;Ｇｕｏｅｔａｌ.,1997;Ｈｏｕ,1998).Ｔｈｅｒｅａｒｅｓｏｍｅｒｅｐｏｒｔｓｔｈａｔｔｈｅｃｏｒｒｏｓｉｏｎｒ… 相似文献
4.
The bacterial flora in the digestive tube of Bullacta exarata Philippi and its rearing shoal were investigated. A to-tal of 157 strains of heterotrophic bacteria, isolated from crop, stomach intestine and other parts of the digestive tube,mainly belong to the genera Photobacterium, Bacillus, Pseudomonas Vibrio and some genera of the family Enterobacteri-aceae. There are significantly more varieties of bacteria in crop than in stomach and intestine. A total of 173 strains of bacte-ria were isolated from the rearing shoal, belonging to 13 genera. The 5 predominant genera, such as Bacillus and Photobac-terium, are the same as those in the digestive tube, but greatly differ in percentages. The number of heterotrophic bacteriaand Vibrio in rearing shoal change in line with the alteration of the temperature, and are significantly affected by the use ofpesticides. 相似文献
5.
Song Xiaoyue Zeng Jiangning Zhou Yi Chen Quanzhen Yang Hongsheng Shou Lu Liao Yibo Huang Wei Du Ping Liu Qiang 《中国海洋湖沼学报》2021,39(1):185-197
Sulfate-reducing bacteria(SRB) are ubiquitous anaerobic microorganisms that play significant roles in the global biogeochemical cycle.Coastal wetlands,one of the major habitats of SRB,exhibit high sulfate-reducing activity and thus play significant roles in organic carbon remineralization,benthic geochemical action,and plant-microbe interactions.Recent studies have provided credible evidence that the functional rather than the taxonomic composition of microbes responds more closely to environmental factors.Therefore.in this study,functional gene prediction based on PacBio single molecular real-time sequencing of 16 S rDNA was applied to deterrmine the sulfate-reducing and organic substrate-decomposing activities of SRB in the rhizospheres of two typical coastal wetland plants in North and South China:Zostera japonica and Scirpus mariqueter.To this end,some physicochemical characteristics of the sediments as well as the phylogenetic structure,community composition,diversity,and proportions of several functional genes of the SRB in the two plant rhizosphere s were analyzed.The Z.japonica meadow had a higher dis similatory sulfate reduction capability than the S.mariqueter-comprising saltmarsh,owing to its larger proportion of SRB in the microbial community,larger proportions of functional genes involved in dissimilatory sulfate reduction,and the stronger ability of the SRB to degrade organic substrates completely.This study confirmed the feasibility of applying microbial community function prediction in research on the metabolic features of SRB,which will be helpful for gaining new knowledge of the biogeochemical and ecological roles of these bacteria in coastal wetlands. 相似文献
6.
New terrestrial habitats have emerged and a primary succession has developed in the retreat area(29°34'N, 102°00'E, 2951–2886 m) after the retreat of the Hailuogou glacier. To investigate soil microbial changes along the primary successional chronosequence, mixed soil samples were collected at six sites at different ages(2 young sites, 2 mid-aged sites, and 2 old sites). The RNA was extracted and amplified. Bacterial 16 S r RNA and fungal 18 S r RNA were analyzed using high-throughput 454 pyrosequencing analysis. Overall, pyrosequencing showed that Proteobacteria, Acidobacteria, Bacteroidetes and Actinobacteria were the main bacterial phyla, and the fungal communities were strongly dominated by the phyla Ascomycota and Basidiomycota in the retreat area. The Shannon diversity index(Hshannon) of bacteria was 6.5 – 7.9, and that of fungi was 2.2 – 4.1 in these sites. For the bacterial communities, diversity and evenness values were highest on the mid-age sites and wererelatively low on the young and old sites. A similar trend was observed for the fungal communities. In contrast, soil properties showed significant linear distributional trends(increase or decrease) with the age of the site. Combining the linear change patterns of soil properties, the highest values of bacterial and fungal evenness and diversity in the mid-aged sites indicated that there was less environmental stress and more niches for microbial communities in the middle successional stage compare with other stages. In addition, our analysis showed that microbial communities were the main drivers that build a soil organic matter pool to expedite pedogenesis for ecosystem succession. This primary succession in the Hailuogou glacier retreat area is developing rapidly compared with that in other glacier retreats. 相似文献
7.
Studies on the diversity and distribution of bacterial populations will improve the overall understanding of the global patterns of marine bacteria and help to comprehend local biochemical processes and environments. We evaluated the composition and the dynamics of bacterial communities in the sediment of Jiaozhou Bay (China) using PCR-denaturing gradient gel electrophoresis (DGGE). Sediment samples were collected from 10 different sites in May, August, and November 2008 and in February 2009. There was significant temporal variation in bacterial community composition at all sites. However, the spatial variation was very small. The DGGE analyses of bacterial communities were used to divide the 10 stations into three types. Canonical correspondence analysis (CCA) revealed that the changes in bacterial communities were driven by sediment properties. Sequence analysis of DGGE band-derived 16S rRNA gene fragments revealed that the dominant bacterial groups in the sediment were of the classes γ-proteobacteria and δ-proteobacteria and phyla Bacteroidetes and Nitrospirae. Our results provide considerable insight into the bacterial community structure in Jiaozhou Bay, China. 相似文献
8.
The sulfate-reducing bacteria (SRB) community in the deep-sea sediments of the west Pacific Warm Pool (WP) was surveyed by molecular phylogenetic analyses using primers targeting the 16S rRNA gene fragments of SRB. Specific 16S rRNA gene libraries from five sediment layers (1-cm, 3-cm, 6-cm, 10-cm and 12-cm layer) of the 12-cm core of WP-0 were constructed. The clones in the five libraries were differentiated by restriction fragment length polymorphism (RFLP) and representative clones were selected to sequence. It was found that the clones fell into four groups, which were closest related to Desulfotomaculum, Desul- facinum, Desulfomonile and Desulfanuticus. Desulfacinum-like clones were only detected in the upper layers of the sediment core, whereas Desulfomonile-like clones were only present in the deeper layers. Fluorescence in situ hybridization (FISH) was further carried out to visualize and count the SRB and bacteria in the five sediment layers. It was found that SRB constituted only a small proportion of the bacteria community (0.34%-1.95%), it had the highest content in the 3-cm layer (1.95%) and had a depth- related decreasing tendency along the 12- cm core. 相似文献
9.
Cao Pan Liu De Liu Yuhan Wang Huming Zhang Chao Yuan Chengqing Liu Xiaodan 《中国海洋湖沼学报》2023,41(1):174-188
Marine biofouling causes serious harms to surfaces of marine devices in transportation, aquaculture, and offshore construction. Traditional antifouling methods pollute the environment. A novel and green antifouling strategy was developed to prevent effectively the adhesion of bacteria and microalgae. An antifouling surface was fabricated via coating Turgencin BMox2 (TB) onto dopamine-modified 304 stainless steel (304 SS). The surface physical and chemical properties before and after modification were characterized by Fourier transform infrared spectrometer (FTIR), X-ray photoelectron spectrometer (XPS), contact angle measurement (CA), 3D optical profilometer, ellipsometer, and atomic force microscope (AFM). Antimicrobial peptide was coated onto the surface of 304 SS successfully, and the surface morphology and wettability of the modified sample were modified. Moreover, cytocompatibility of the peptide was evaluated by co-culture of peptide and cells, indicating promising cell biocompatibility at the modified sample surface. At last, antifouling performance and electrochemical corrosion were tested. Results show that the adhesion rates of Vibrio natriegens and Phaeodactylum tricornutum on the antifouling surface were reduced by 99.85% and 67.93%, respectively from those of untreated samples. Therefore, the modified samples retained superior corrosion resistance. The study provide a simply and green way against biofouling on ship hulls and marine equipment.
相似文献10.
《中国海洋大学学报(英文版)》2016,(6)
Bacterial community presumably plays an essential role in inhibiting pathogen colonization and maintaining the health of scallop larvae, but limiting data are available for Yesso scallop(Patinopecten yessoensisis Jay, 1857) larval development stages. The aim of this study was to characterize and compare the bacterial communities associating with Yesso scallop larval development at fertilized egg S1, trochophora S2, D-shaped larvae S3, umbo larvae S4, and juvenile scallop S5 stages by Illumina high-throughput sequencing. Genomic DNA was extracted from the larvae and their associating bactera, and a gene segment covering V3-V4 region of 16 S r RNA gene was amplified and sequenced using an Illumina Miseq sequencer. Overall, 106760 qualified sequences with an average length of 449 bp were obtained. Sequences were compared with those retrieved from 16 S r RNA gene databases, and 4 phyla, 7 classes, 15 orders, 21 families, 31 genera were identified. Proteobacteria was predominant phylum, accounting for more than 99%, at all 5 larval development stages. At genus level, Pseudomonas was dominant at stages S1(80.60%), S2(87.77%) and S5(68.71%), followed by Photobacterium(17.06%) and Aeromonas(1.64%) at stage S1, Serratia(6.94%), Stenotrophomonas(3.08%) and Acinetobacter(1.2%) at stage S2, Shewanella(25.95%) and Pseudoalteromonas(4.57%) at stage S5. Moreover, genus Pseudoalteromonas became dominant at stages S3(44.85%) and S4(56.02%), followed by Photobacterium(29.82%), Pseudomonas(11.86%), Aliivibrio(8.60%) and Shewanella(3.39%) at stage S3, Pseudomonas(18.16%), Aliivibrio(14.29%), Shewanella(4.11%), Psychromonas(4.04%) and Psychrobacter(1.81%) at stage S4. From the results, we concluded that the bacterial community changed significantly at different development stages of Yesso Scallop larvae. 相似文献
11.
Sulfate-reducing bacteria (SRB), which obtain energy from dissimilatory sulfate reduction, play a vital role in the carbon and sulfur cycles. The dissimilatory sulfite reductase (Dsr), catalyzing the last step in the sulfate reduction pathway, has been found in all known SRB that have been tested so far. In this study, the diversity of SRB was investigated in the surface sediments from the adjacent area of Changjiang Estuary by PCR amplification, cloning and sequencing of the dissimilatory sulfite reductase beta subunit gene (dsrB). Based on dsrB clone libraries constructed in this study, diversified SRB were found, represented by 173 unique OTUs. Certain cloned sequences were associated with Desulfobacteraceae, Desulfobulbaceae, and a large fraction (60%) of novel sequences that have deeply branched groups in the dsrB tree, indicating that novel SRB inhabit the surface sediments. In addition, correlations of the SRB assemblages with environmental factors were analyzed by the linear model-based redundancy analysis (RDA). The result revealed that temperature, salinity and the content of TOC were most closely correlated with the SRB communities. More information on SRB community was obtained by applying the utility of UniFrac to published dsrB gene sequences from this study and other 9 different kinds of marine environments. The results demonstrated that there were highly similar SRB genotypes in the marine and estuarine sediments, and that geographic positions and environmental factors influenced the SRB community distribution. 相似文献
12.
Bacterial diversity in sea ice brine samples which collected from four stations located at the Canada Basin, Arctic Ocean was analyzed by PCR-DGGE. Twenty-three 16S rDNA sequences of bacteria obtained from DGGE bands were cloned and sequenced. Phylogenetic analysis clustered these sequences within γ-proteobacteria, Cytophaga-Flexlbacter-Bacteroides （CFB） group, Firmicutes and Actinobacteria. The phylotype of Pseudoalteromonas in the γ-proteobacteria was predominant and members of the CFB group and γ-proteobacteria were highly abundant in studied sea ice brine samples. 相似文献
13.
Reduced graphene sheets (RGSs) mediate electron transfer between sulfate-reducing bacteria (SRB) and solid electrodes, and promote the development of microbial fuel cells (MFC). We have investigated RSG-promoted electron transfer between SRB and a glassy carbon (GC) electrode. The RGSs were produced at high yield by a chemical sequence involving graphite oxidation, ultrasonic exfoliation of nanosheets, and N2H4 reduction. Cyclic voltammetric testing showed that the characteristic anodic peaks (around 0.3 V) might arise from the combination of bacterial membrane surface cytochrome c3 and the metabolic products of SRB. After 6 d, another anodic wave gradually increased to a maximum current peak and a third anodic signal became visible at around 0 V. The enhancements of two characteristic anodic peaks suggest that RSGs mediate electron-transfer kinetics between bacteria and the solid electrode. Manipulation of these recently-discovered electron-transport mechanisms will lead to significant advances in MFC engineering. 相似文献
14.
This study was conducted to evaluate the impact of hazy and foggy weather on the bacterial communities in bioaerosols, for which samples were collected from the Qingdao coastal region on sunny, foggy, and hazy days in January and March 2013. Bacterial community compositions were determined using polymerase chain reaction denaturing gradient gel electrophoresis (PCRDGGE). The bacterial community diversity was found to be high on foggy and hazy days, and the dominant species differed during hazy weather. The Shannon-Wiener index revealed that the bacterial community diversity of coarse particles was higher than that of fine particles in the bioaerosols. The bacterial community diversity of fine particles significantly correlated with relative humidity (RH; r2 = 0.986). The cluster analysis results indicated that the bacterial communities on sunny days differed from those on hazy and foggy days. Compared with sunny days, the bacterial communities in the fine particles during hazy weather exhibited greater changes than those in the coarse particles. Most of the sequenced bacteria were found to be closely affiliated with uncultured bacteria. During hazy weather, members of the classes Bacilli and Gammaproteobacteria (Pseudomonas and Acinetobacter) were dominant. The DGGE analysis revealed that Proteobacteria and Firmicutes were the predominant phyla, and their relative percentages to all the measured species changed significantly on hazy days, particularly in the fine particles. Haze and fog had a significant impact on the bacterial communities in bioaerosols, and the bacterial community diversity varied on different hazy days. 相似文献
15.
The Drake Passage is located between the Antarctic Peninsula and Tierra del Fuego in the south of South America. Surface seawater samples were collected at seven sites in the Drake Passage during the austral summer of 2012. The 16S rRNA sequences were analyzed from 187 isolated bacterial strains. Three phyla, 29 genera and 56 species were identified. The three phyla were Actinobacteria, Firmicutes and Proteobacteria; the Proteobacteria included α-Proteobacteria, β-Proteobacteria and γ-Proteobacteria. γ-Proteobacteria, Actinobacteria and Firmicutes were the dominant class or phyla in terms of quantity and species. Gram-positive bacteria (Actinobacteria and Firmicutes) accounted for 57.8% of all types identified. There were nine dominant genera, including Curtobacterium, Staphylococcus, and Halomonas, and 14 dominant species including Curtobacterium flaccumfaciens, Curtobacterium pusillum, and Staphylococcus sciuri. Of the strains identified, 87.2% were catalase positive or weakly positive. 相似文献
16.
lNTRODUCTI0NSincetheoonceptofrnarinesplashzone(MSZ)wasfirstproposedbyHumble,rnanyresearchesprovedthatthecorrosionofsteelinthesplashzoneisthemostseriousinthemarineenvironninetandthatthisMSZcorrosionhasapeak(Zhu,l995).Howevertheenvironmentalfactorscatisingthecorrosionpeakwasnotkn0wnthen(Niat0,l975,Atsushi,l994)andtherangeoftheMSZwasnotyetdeariydefinedopzkaki,l985).ThispaperexplainsthemaincauseofthecormsionpeakanddefinestheexaCtrangeoftheMSZinsomeofChina'sharbours.MATERIALSANDMET… 相似文献
17.
We investigated the bacterioplankton abundance,community composition and the associated Vibrio clades of natural seawater in Bohai Sea coastal waters.Seawater samples(10 L in triplicate)were collected at 0.5,3,and 5 m depths near the coastal aquaculture zone of the Bohai Sea on May 12,2016.Real-time PCR and 16 S rRNA gene amplicon high-throughput sequencing methods were employed by which 485 operational taxonomic units(OTUs)at a 97% sequence similarity level were generated.Gammaproteobacteria,Alphaproteobacteria,and Bacteroidetes were the most abundant groups,accounting for 49.5%,23.5%,and 18.9% ofthe total assemblage,respectively.Obvious variations in Pseudoalteromonas,Vibrio,and Octadecabacter,which were the most abundant genera,could be observed among different samples.Notably,the results of Vibrio-specific real-time PCR indicated that Vibrio had extremely high 16 S rRNA gene copy numbers.The 16 S rRNA gene sequencing results across all the samples also indicated that they occupied a large proportion of the total assemblage.Both the alpha diversity and major bacterioplankton group Pseudoalteromonas had significant correlations with the concentration of PO43-.Overall,studies on bacterioplankton communities with highly abundant Vibrio clades can provide interesting insight into the microbial function and health assessment of the Bohai Sea coastal ecosystem. 相似文献
18.
GAO Rongjie DU Min SUN Xiaoxia PU Yanli 《中国海洋大学学报(英文版)》2007,6(4):349-354
The corrosion resistance of electroless Ni-P deposits with phosphorous contents from 12% to 14% in sodium chloride solutions was studied. The deposits were immersed in 3.5% NaCl solutions for 29 d to obtain the electrochemical parameters and were examined in a standard salt spray test for 15 d respectively. The corrosion resistance of the deposits was studied by poten- tio-dynamic scan, electrochemical impedance spectroscopy (EIS), X-ray diffraction (XRD) and cold-field emission scanning electron microscopy (FE-SEM) equipped with an energy dispersive X-ray detector (EDX). The patterns of XRD and the results of FE-SEM showed that the prepared deposits were amorphous. But after a 15 d standard salt spray test, a few pinholes appeared on the surface of the deposit and the weight content of phosphorus on the surface of the deposit was higher (which was beneficial to the formation of the passivation films) than that before the standard salt spray test when the nickel content was lower because the dissolved weight of nickel was greater than that of phosphorus. The results from potentio-dynamic scan and EIS showed that passivation films formed on the Ni-P deposit after immersion in the NaCl solutions, which decreased the corrosion rate of Ni-P samples. The results of this work show their potential applications in marine corrosion. 相似文献
19.
The soil microbiome that plays important ecological roles in mountains and forests is influenced by anthropogenic and natural causes. Human activity, particularly harvesting or thinning, affects the soil microbiome in forests by altering environmental conditions, such as vegetation, microclimate, and soil physicochemical properties. The purpose of this study was to investigate the effects on forest thinning on the diversity and composition of the soil bacterial community. From next-generation sequencing results of the 16S rRNA gene, we examined differences in soil bacterial diversity and community composition before and after thinning at Mt. Janggunbong, South Korea. We identified 40 phyla, 103 classes, 192 orders, 412 families, 947 genera, and 3,145 species from the soil samples. Acidobacteria and Proteobacteria were the most dominant bacterial phyla in the forest soil of Mt. Janggunbong. Soil bacterial diversity measures (richness, Shannon diversity index, and evenness) at the phylum level increased after thinning, whereas species-level taxonomic richness decreased after thinning. Thinning provided new opportunities for bacterial species in Chloroflexi, Verrucomicrobia, Nitrospirae, and other nondominant bacterial taxa, especially for those not found in Mt. Janggunbong before thinning, to settle and adapt to the changing environment. Our results suggested that thinning affected the diversity and composition of soil bacterial communities in forests and mountains. 相似文献
20.
Bacterial diversity and community structure in the East China Sea by 454 sequencing of the 16S rRNA gene 总被引：1，自引：0，他引：1
The 454 sequencing method was used to detect bacterial diversity and community structure in the East China Sea. Overall, 149 067 optimized reads with an average length of 454 nucleotides were obtained from 17 seawater samples and five sediment samples sourced in May 2011. A total of 22 phyla, 34 classes, 74 orders, 146 families, and 333 genera were identified in this study. Some of them were detected for the first time from the East China Sea. The estimated richness and diversity indices were both higher in the sediment samples compared with in the seawater samples. All the samples were divided by their diversity indices into four regions. Similarity analysis showed that the seawater samples could be classified into six groups. The groups differed from each other and had unique community structure characteristics. It was found that different water masses in the sampling areas may have had some influence on the bacterial community structure. A canonical correspondence analysis revealed that seawater samples in different areas and at different depths were affected by different environmental parameters. This study will lay the foundation for future research on microbiology in the East China Sea. 相似文献