scholarly journals Native and Invading Yellow Starthistle (Centaurea solstitialis) Microbiomes Differ in Composition and Diversity of Bacteria

mSphere ◽  
2019 ◽  
Vol 4 (2) ◽  
Author(s):  
Patricia Lu-Irving ◽  
Julia G. Harenčár ◽  
Hailey Sounart ◽  
Shana R. Welles ◽  
Sarah M. Swope ◽  
...  

ABSTRACTInvasive species could benefit from being introduced to locations with more favorable species interactions, including the loss of enemies, the gain of mutualists, or the simplification of complex interaction networks. Microbiomes are an important source of species interactions with strong fitness effects on multicellular organisms, and these interactions are known to vary across regions. The highly invasive plant yellow starthistle (Centaurea solstitialis) has been shown to experience more favorable microbial interactions in its invasions of the Americas, but the microbiome that must contribute to this variation in interactions is unknown. We sequenced amplicons of 16S rRNA genes to characterize bacterial community compositions in the phyllosphere, ectorhizosphere, and endorhizosphere of yellow starthistle plants from seven invading populations in California, USA, and eight native populations in Europe. We tested for the differentiation of microbiomes by geography, plant compartment, and plant genotype. Bacterial communities differed significantly between native and invading plants within plant compartments, with consistently lower diversity in the microbiome of invading plants. The diversity of bacteria in roots was positively correlated with plant genotype diversity within both ranges, but this relationship did not explain microbiome differences between ranges. Our results reveal that these invading plants are experiencing either a simplified microbial environment or simplified microbial interactions as a result of the dominance of a few taxa within their microbiome. Our findings highlight several alternative hypotheses for the sources of variation that we observe in invader microbiomes and the potential for altered bacterial interactions to facilitate invasion success.IMPORTANCEPrevious studies have found that introduced plants commonly experience more favorable microbial interactions in their non-native range, suggesting that changes to the microbiome could be an important contributor to invasion success. Little is known about microbiome variation across native and invading populations, however, and the potential sources of more favorable interactions are undescribed. Here, we report one of the first microbiome comparisons of plants from multiple native and invading populations, in the noxious weed yellow starthistle. We identify clear differences in composition and diversity of microbiome bacteria. Our findings raise new questions about the sources of these differences, and we outline the next generation of research that will be required to connect microbiome variation to its potential role in plant invasions.

2017 ◽  
Author(s):  
Patricia Lu-Irving ◽  
Julia Harenčár ◽  
Hailey Sounart ◽  
Shana R Welles ◽  
Sarah M Swope ◽  
...  

SUMMARYInvasive species could benefit from introduction to locations with favorable species interactions. Microbiomes are an important source of interactions that vary across regions. We examine whether bacterial communities could explain more favorable microbial interactions in highly invasive populations of yellow starthistle.We sequenced amplicons of prokaryotic 16S rRNA genes to characterize bacterial community composition in the phyllosphere, ectorhizosphere, and endorhizosphere of plants from seven invading populations in California, USA and eight native populations in Europe. We tested for differentiation of microbiomes by geography, plant compartment, and plant genotype.Bacterial communities differed significantly between native and invaded ranges within plant compartments, with consistently lower diversity in plants from the invaded range. Genera containing known plant pathogens also showed lower diversity in invaded range plants. The diversity of bacteria in roots was positively correlated with plant genotype diversity within both ranges, but this relationship did not explain microbial differences between ranges.Our findings reveal changes in the composition and diversity of bacterial interactions in invading plants, consistent with observations of altered soil interactions in this invasion. These results call for further study of the sources of variation in microbiomes and the potential for bacteria to facilitate invasion success.


2014 ◽  
Vol 64 (Pt_5) ◽  
pp. 1501-1506 ◽  
Author(s):  
Bacem Mnasri ◽  
Tian Yan Liu ◽  
Sabrine Saidi ◽  
Wen Feng Chen ◽  
Wen Xin Chen ◽  
...  

Three microbial strains isolated from common beans, 23C2T (Tunisia), Gr42 (Spain) and IE4868 (Mexico), which have been identified previously as representing a genomic group closely related to Rhizobium gallicum , are further studied here. Their 16S rRNA genes showed 98.5–99 % similarity with Rhizobium loessense CCBAU 7190BT, R. gallicum R602spT, Rhizobium mongolense USDA 1844T and Rhizobium yanglingense CCBAU 71623T. Phylogenetic analysis based on recA, atpD, dnaK and thrC sequences showed that the novel strains were closely related and could be distinguished from the four type strains of the closely related species. Strains 23C2T, Gr42 and IE4868 could be also differentiated from their closest phylogenetic neighbours by their phenotypic and physiological properties and their fatty acid contents. All three strains harboured symbiotic genes specific to biovar gallicum. Levels of DNA–DNA relatedness between strain 23C2T and the type strains of R. loessense , R. mongolense , R. gallicum and R. yanglingense ranged from 58.1 to 61.5 %. The DNA G+C content of the genomic DNA of strain 23C2T was 59.52 %. On the basis of these data, strains 23C2T, Gr42 and IE4868 were considered to represent a novel species of the genus Rhizobium for which the name Rhizobium azibense is proposed. Strain 23C2T ( = CCBAU 101087T = HAMBI3541T) was designated as the type strain.


2016 ◽  
Vol 82 (10) ◽  
pp. 3022-3031 ◽  
Author(s):  
Ayako Fujiwara ◽  
Katsuhiro Kawato ◽  
Saori Kato ◽  
Kiyoshi Yasukawa ◽  
Ryota Hidese ◽  
...  

ABSTRACTDNA/RNA helicases, which are enzymes for eliminating hydrogen bonds between bases of DNA/DNA, DNA/RNA, and RNA/RNA using the energy of ATP hydrolysis, contribute to various biological activities. In the present study, theEuryarchaeota-specific helicase EshA (TK0566) from the hyperthermophilic archaeonThermococcus kodakarensis(Tk-EshA) was obtained as a recombinant form, and its enzymatic properties were examined.Tk-EshA exhibited maximal ATPase activity in the presence of RNA at 80°C. Unwinding activity was evaluated with various double-stranded DNAs (forked, 5′ overhung, 3′ overhung, and blunt end) at 50°C.Tk-EshA unwound forked and 3′ overhung DNAs. These activities were expected to unwind the structured template and to peel off misannealed primers whenTk-EshA was added to a PCR mixture. To examine the effect ofTk-EshA on PCR, various target DNAs were selected, and DNA synthesis was investigated. When 16S rRNA genes were used as a template, several misamplified products (noise DNAs) were detected in the absence ofTk-EshA. In contrast, noise DNAs were eliminated in the presence ofTk-EshA. Noise reduction byTk-EshA was also confirmed whenTaqDNA polymerase (a family A DNA polymerase, PolI type) and KOD DNA polymerase (a family B DNA polymerase, α type) were used for PCR. Misamplified bands were also eliminated duringtoxAgene amplification fromPseudomonas aeruginosaDNA, which possesses a high GC content (69%).Tk-EshA addition was more effective than increasing the annealing temperature to reduce misamplified DNAs duringtoxAamplification.Tk-EshA is a useful tool to reduce noise DNAs for accurate PCR.IMPORTANCEPCR is a technique that is useful for genetic diagnosis, genetic engineering, and detection of pathogenic microorganisms. However, troubles with nonspecific DNA amplification often occur from primer misannealing. In order to achieve a specific DNA amplification by eliminating noise DNAs derived from primer misannealing, a thermostableEuryarchaeota-specific helicase (Tk-EshA) was included in the PCR mixture. The addition ofTk-EshA has reduced noise DNAs in PCR.


2013 ◽  
Vol 63 (Pt_4) ◽  
pp. 1471-1478 ◽  
Author(s):  
Morio Ishikawa ◽  
Kazuhide Yamasato ◽  
Kayo Kodama ◽  
Hinako Yasuda ◽  
Mioko Matsuyama ◽  
...  

Nine novel strains of halophilic and alkaliphilic lactic acid bacteria isolated from European soft and semi-hard cheeses by using a saline, alkaline medium (7 % NaCl, pH 9.5) were taxonomically characterized. The isolates were Gram-stain-positive, non-sporulating and non-motile. They lacked catalase and quinones. Under anaerobic cultivation conditions, lactate was produced from d-glucose with the production of formate, acetate and ethanol with a molar ratio of approximately 2 : 1 : 1. Under aerobic cultivation conditions, acetate and lactate were produced from d-glucose. The isolates were slightly halophilic, highly halotolerant and alkaliphilic. The optimum NaCl concentration for growth ranged between 2.0 % and 5.0 % (w/v), with a growth range of 0–1 % to 15–17.5 %. The optimum pH for growth ranged between 8.5 and 9.5, with a growth range of 7.0–7.5 to 9.5–10.0. Comparative sequence analysis of the 16S rRNA genes revealed that the isolates occupied a phylogenetic position within the genus Alkalibacterium , showing the highest sequence similarity (98.2 %) to Alkalibacterium kapii T22-1-2T. The isolates constituted a single genomic species with DNA–DNA hybridization values of 79–100 % among the isolates and <29 % between the isolates and other members of the genus Alkalibacterium , from which the isolates were different in motility and flagellation, growth responses to NaCl concentrations and pH, and profiles of sugar fermentation. The DNA G+C contents were between 36.0 and 37.6 mol%. The cell-wall peptidoglycan was type A4β, Orn-d-Asp. The major components of cellular fatty acids were C14 : 0, C16 : 0 and C16 : 1ω9c. Based on the phenotypic characteristics and genetic distinctness, the isolates are classified as a novel species within the genus Alkalibacterium , for which the name Alkalibacterium gilvum sp. nov. is proposed. The type strain is 3AD-1T ( = DSM 25751T = JCM 18271T).


2013 ◽  
Vol 63 (Pt_3) ◽  
pp. 861-866 ◽  
Author(s):  
Hirokazu Shimoshige ◽  
Tomoaki Yamada ◽  
Hiroaki Minegishi ◽  
Akinobu Echigo ◽  
Yasuhiro Shimane ◽  
...  

Two extremely halophilic archaea, strains MGY-184T and MGY-205, were isolated from sea salt produced in Japan and rock salt imported from Bolivia, respectively. Both strains were pleomorphic, non-motile, Gram-negative and required more than 5 % (w/v) NaCl for growth, with optimum at 9–12 %, in the presence of 2 % (w/v) MgCl2 . 6H2O. In the presence of 18 % (w/v) MgCl2 . 6H2O, however, both strains showed growth even at 1.0 % (w/v) NaCl. Both strains possessed two 16S rRNA genes (rrnA and rrnB), and they revealed closest similarity to Halobaculum gomorrense JCM 9908T, the single species with a validly published name of the genus Halobaculum , with similarity of 97.8 %. The rrnA and rrnB genes of both strains were 100 % similar. The rrnA genes were 97.6 % similar to the rrnB genes in both strains. DNA G+C contents of strains MGY-184T and MGY-205 were 67.0 and 67.4 mol%, respectively. Polar lipid analysis revealed that the two strains contained phosphatidylglycerol and phosphatidylglycerol phosphate methyl ester derived from C20C20 archaeol. The DNA–DNA hybridization value between the two strains was 70 % and both strains showed low levels of DNA–DNA relatedness (48–50 %) with Halobaculum gomorrense JCM 9908T. Physiological and biochemical characteristics allowed differentiation of strains MGY-184T and MGY-205 from Halobaculum gomorrense JCM 9908T. Therefore, strains MGY-184T and MGY-205 represent a novel species of the genus Halobaculum , for which the name Halobaculum magnesiiphilum sp. nov. is proposed; the type strain is MGY-184T ( = JCM 17821T = KCTC 4100T).


2017 ◽  
Vol 83 (16) ◽  
Author(s):  
Daniel S. Jones ◽  
Kim A. Lapakko ◽  
Zachary J. Wenz ◽  
Michael C. Olson ◽  
Elizabeth W. Roepke ◽  
...  

ABSTRACT The Duluth Complex in northeastern Minnesota hosts economically significant deposits of copper, nickel, and platinum group elements (PGEs). The primary sulfide mineralogy of these deposits includes the minerals pyrrhotite, chalcopyrite, pentlandite, and cubanite, and weathering experiments show that most sulfide-bearing rock from the Duluth Complex generates moderately acidic leachate (pH 4 to 6). Microorganisms are important catalysts for metal sulfide oxidation and could influence the quality of water from mines in the Duluth Complex. Nevertheless, compared with that of extremely acidic environments, much less is known about the microbial ecology of moderately acidic sulfide-bearing mine waste, and so existing information may have little relevance to those microorganisms catalyzing oxidation reactions in the Duluth Complex. Here, we characterized the microbial communities in decade-long weathering experiments (kinetic tests) conducted on crushed rock and tailings from the Duluth Complex. Analyses of 16S rRNA genes and transcripts showed that differences among microbial communities correspond to pH, rock type, and experimental treatment. Moreover, microbial communities from the weathered Duluth Complex rock were dominated by taxa that are not typically associated with acidic mine waste. The most abundant operational taxonomic units (OTUs) were from the genera Meiothermus and Sulfuriferula, as well as from diverse clades of uncultivated Chloroflexi, Acidobacteria, and Betaproteobacteria. Specific taxa, including putative sulfur-oxidizing Sulfuriferula spp., appeared to be primarily associated with Duluth Complex rock, but not pyrite-bearing rocks subjected to the same experimental treatment. We discuss the implications of these results for the microbial ecology of moderately acidic mine waste with low sulfide content, as well as for kinetic testing of mine waste. IMPORTANCE Economic sulfide mineral deposits in the Duluth Complex may represent the largest undeveloped source of copper and nickel on Earth. Microorganisms are important catalysts for sulfide mineral oxidation, and research on extreme acidophiles has improved our ability to manage and remediate mine wastes. We found that the microbial assemblages associated with weathered rock from the Duluth Complex are dominated by organisms not widely associated with mine waste or mining-impacted environments, and we describe geochemical and experimental influences on community composition. This report will be a useful foundation for understanding the microbial biogeochemistry of moderately acidic mine waste from these and similar deposits.


2011 ◽  
Vol 77 (14) ◽  
pp. 5009-5017 ◽  
Author(s):  
Ilaria Pizzetti ◽  
Bernhard M. Fuchs ◽  
Gunnar Gerdts ◽  
Antje Wichels ◽  
Karen H. Wiltshire ◽  
...  

ABSTRACTMembers of the bacterial phylumPlanctomycetesare reported in marine water samples worldwide, but quantitative information is scarce. Here we investigated the phylogenetic diversity, abundance, and distribution ofPlanctomycetesin surface waters off the German North Sea island Helgoland during different seasons by 16S rRNA gene analysis and catalyzed reporter deposition fluorescencein situhybridization (CARD-FISH). GenerallyPlanctomycetesare more abundant in samples collected in summer and autumn than in samples collected in winter and spring. Statistical analysis revealed thatPlanctomycetesabundance was correlated to theCentralesdiatom bloom in spring 2007. The analysis of size-fractionated seawater samples and of macroaggregates showed that ∼90% of thePlanctomycetesreside in the >3-μm size fraction. Comparative sequence analysis of 184 almost full-length 16S rRNA genes revealed three dominant clades. The clades, namedPlanctomyces-related group A, unculturedPlanctomycetesgroup B, andPirellula-related group D, were monitored by CARD-FISH using newly developed oligonucleotide probes. All three clades showed recurrent abundance patterns during two annual sampling campaigns. UnculturedPlanctomycetesgroup B was most abundant in autumn samples, whilePlanctomyces-related group A was present in high numbers only during late autumn and winter. The levels ofPirellula-related group D were more constant throughout the year, with elevated counts in summer. Our analyses suggest that the seasonal succession of thePlanctomycetesis correlated with algal blooms. We hypothesize that the niche partitioning of the different clades might be caused by their algal substrates.


2019 ◽  
Vol 85 (11) ◽  
Author(s):  
Mustapha Mohammed ◽  
Sanjay K. Jaiswal ◽  
Felix D. Dakora

ABSTRACTKersting’s groundnut [Macrotyloma geocarpum(Harms) Marechal & Baudet] is a neglected indigenous African legume adapted to growth in N-deficient soils due to its ability to fix atmospheric N2via symbiosis with rhizobia. Despite its nutritional and medicinal uses, to date there is little information on the phylogeny and functional traits of its microsymbionts, aspects that are much needed for its conservation and improvement. This study explored the morphogenetic diversity, phylogenetic relationships, and N2-fixing efficiency of Kersting’s groundnut rhizobial isolates from contrasting environments in Ghana, South Africa, and Mozambique. BOX-PCR fingerprinting revealed high diversity among the rhizobial populations, which was influenced by geographic origin. Of the 164 isolates evaluated, 130 BOX-PCR types were identified at a 70% similarity coefficient, indicating that they were not clones. Soil pH and mineral concentrations were found to influence the distribution of bradyrhizobial populations in African soils. Phylogenetic analysis of 16S rRNA genes and multilocus sequence analysis of protein-coding genes (atpD,glnII,gyrB, andrpoB) and symbiotic genes (nifHandnodC) showed that Kersting’s groundnut is primarily nodulated by members of the genusBradyrhizobium, which are closely related toBradyrhizobium vignae7-2T,Bradyrhizobium kavangense14-3T,Bradyrhizobium subterraneum58-2-1T,Bradyrhizobium pachyrhiziPAC48T, the type strain ofBradyrhizobium elkanii, and novel groups ofBradyrhizobiumspecies. The bradyrhizobial populations identified exhibited high N2fixation and induced greater nodulation, leaf chlorophyll concentration, and photosynthetic rates in their homologous host than did the 5 mM KNO3-fed plants and/or the commercialBradyrhizobiumsp. strain CB756, suggesting that they could be good candidates for inoculant formulations upon field testing.IMPORTANCERhizobia play important roles in agroecosystems, where they contribute to improving overall soil health through their symbiotic relationship with legumes. This study explored the microsymbionts nodulating Kersting’s groundnut, a neglected orphan legume. The results revealed the presence of different bradyrhizobial populations with high N2-fixing efficiencies as the dominant symbionts of this legume across diverse agroecologies in Africa. Our findings represent a useful contribution to the literature in terms of the community of microsymbionts nodulating a neglected cultivated legume and its potential for elevation as a major food crop. The presence of potentially novel bradyrhizobial symbionts of Kersting’s groundnut found in this study offers an opportunity for future studies to properly describe, characterize, and delineate these isolates functionally and phylogenetically for use in inoculant production to enhance food/nutritional security.


2015 ◽  
Vol 81 (23) ◽  
pp. 8066-8075 ◽  
Author(s):  
David Emerson ◽  
Jarrod J. Scott ◽  
Joshua Benes ◽  
William B. Bowden

ABSTRACTThe role that neutrophilic iron-oxidizing bacteria play in the Arctic tundra is unknown. This study surveyed chemosynthetic iron-oxidizing communities at the North Slope of Alaska near Toolik Field Station (TFS) at Toolik Lake (lat 68.63, long −149.60). Microbial iron mats were common in submerged habitats with stationary or slowly flowing water, and their greatest areal extent is in coating plant stems and sediments in wet sedge meadows. Some Fe-oxidizing bacteria (FeOB) produce easily recognized sheath or stalk morphotypes that were present and dominant in all the mats we observed. The cool water temperatures (9 to 11°C) and reduced pH (5.0 to 6.6) at all sites kinetically favor microbial iron oxidation. A microbial survey of five sites based on 16S rRNA genes found a predominance ofProteobacteria, withBetaproteobacteriaand members of the familyComamonadaceaebeing the most prevalent operational taxonomic units (OTUs). In relative abundance, clades of lithotrophic FeOB composed 5 to 10% of the communities. OTUs related to cyanobacteria and chloroplasts accounted for 3 to 25% of the communities. Oxygen profiles showed evidence for oxygenic photosynthesis at the surface of some mats, indicating the coexistence of photosynthetic and FeOB populations. The relative abundance of OTUs belonging to putative Fe-reducing bacteria (FeRB) averaged around 11% in the sampled iron mats. Mats incubated anaerobically with 10 mM acetate rapidly initiated Fe reduction, indicating that active iron cycling is likely. The prevalence of iron mats on the tundra might impact the carbon cycle through lithoautotrophic chemosynthesis, anaerobic respiration of organic carbon coupled to iron reduction, and the suppression of methanogenesis, and it potentially influences phosphorus dynamics through the adsorption of phosphorus to iron oxides.


2014 ◽  
Vol 64 (Pt_7) ◽  
pp. 2274-2279 ◽  
Author(s):  
Cheol Su Park ◽  
Kyudong Han ◽  
Tae-Young Ahn

A Gram-staining-negative, strictly aerobic, rod-shaped, pale-pink pigmented bacterial strain, designated TF8T, was isolated from leaf mould in Cheonan, Republic of Korea. Its taxonomic position was determined through a polyphasic approach. Optimal growth occurred on R2A agar without NaCl supplementation, at 25–28 °C and at pH 6.0–7.0. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain TF8T belongs to the genus Mucilaginibacter in the family Sphingobacteriaceae . The sequence similarity between 16S rRNA genes of strain TF8T and the type strains of other species of the genus Mucilaginibacter ranged from 92.1 to 94.7 %. The closest relatives of strain TF8T were Mucilaginibacter lutimaris BR-3T (94.7 %), M. soli R9-65T (94.5 %), M. litoreus BR-18T (94.5 %), M. rigui WPCB133T (94.0 %) and M. daejeonensis Jip 10T (93.8 %). The major isoprenoid quinone was MK-7 and the major cellular fatty acids were iso-C15 : 0 (33.0 %), summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c; 24.8 %) and summed feature 8 (C18 : 1ω7c and/or C18 : 1ω6c; 13.0 %). The major polar lipids of TF8T were phosphatidylethanolamine and three unidentified aminophospholipids. The G+C content of the genomic DNA was 46.2 mol%. On the basis of the data presented here, strain TF8T is considered to represent a novel species of the genus Mucilaginibacter , for which the name Mucilaginibacter koreensis sp. nov. is proposed. The type strain is TF8T ( = KACC 17468T = JCM 19323T).


Sign in / Sign up

Export Citation Format

Share Document