scholarly journals Molecular Analysis of Carbon Monoxide-Oxidizing Bacteria Associated with Recent Hawaiian Volcanic Deposits

2004 ◽  
Vol 70 (7) ◽  
pp. 4242-4248 ◽  
Author(s):  
Kari E. Dunfield ◽  
Gary M. King
Keyword(s):  
Carbon Monoxide ◽  
Lava Flow ◽  
Large Subunit ◽  
Pcr Amplification ◽  
Pcr Primers ◽  
Clone Libraries ◽  
Tephra Deposit ◽  
Volcanic Deposits ◽  
Pcr Products ◽  
Phylogenetic Lineages

ABSTRACT Genomic DNA extracts from four sites at Kilauea Volcano were used as templates for PCR amplification of the large subunit (coxL) of aerobic carbon monoxide dehydrogenase. The sites included a 42-year-old tephra deposit, a 108-year-old lava flow, a 212-year-old partially vegetated ash-and-tephra deposit, and an approximately 300-year-old forest. PCR primers amplified coxL sequences from the OMP clade of CO oxidizers, which includes isolates such as Oligotropha carboxidovorans, Mycobacterium tuberculosis, and Pseudomonas thermocarboxydovorans. PCR products were used to create clone libraries that provide the first insights into the diversity and phylogenetic affiliations of CO oxidizers in situ. On the basis of phylogenetic and statistical analyses, clone libraries for each site were distinct. Although some clone sequences were similar to coxL sequences from known organisms, many sequences appeared to represent phylogenetic lineages not previously known to harbor CO oxidizers. On the basis of average nucleotide diversity and average pairwise difference, a forested site supported the most diverse CO-oxidizing populations, while an 1894 lava flow supported the least diverse populations. Neither parameter correlated with previous estimates of atmospheric CO uptake rates, but both parameters correlated positively with estimates of microbial biomass and respiration. Collectively, the results indicate that the CO oxidizer functional group associated with recent volcanic deposits of the remote Hawaiian Islands contains substantial and previously unsuspected diversity.

scholarly journals Analysis of Facultative Lithotroph Distribution and Diversity on Volcanic Deposits by Use of the Large Subunit of Ribulose 1,5-Bisphosphate Carboxylase/Oxygenase

2004 ◽  
Vol 70 (4) ◽  
pp. 2245-2253 ◽  
Author(s):  
K. Nanba ◽  
G. M. King ◽  
K. Dunfield
Keyword(s):  
Nucleotide Diversity ◽  
Microbial Mats ◽  
Phylogenetic Analyses ◽  
Large Subunit ◽  
Hydrogen Uptake ◽  
Clone Libraries ◽  
Bisphosphate Carboxylase ◽  
Gene Coding ◽  
Volcanic Deposits ◽  
Pcr Products

ABSTRACT A 492- to 495-bp fragment of the gene coding for the large subunit of the form I ribulose 1,5-bisphosphate carboxylase/oxygenase (RubisCO) (rbcL) was amplified by PCR from facultatively lithotrophic aerobic CO-oxidizing bacteria, colorless and purple sulfide-oxidizing microbial mats, and genomic DNA extracts from tephra and ash deposits from Kilauea volcano, for which atmospheric CO and hydrogen have been previously documented as important substrates. PCR products from the mats and volcanic sites were used to construct rbcL clone libraries. Phylogenetic analyses showed that the rbcL sequences from all isolates clustered with form IC rbcL sequences derived from facultative lithotrophs. In contrast, the microbial mat clone sequences clustered with sequences from obligate lithotrophs representative of form IA rbcL. Clone sequences from volcanic sites fell within the form IC clade, suggesting that these sites were dominated by facultative lithotrophs, an observation consistent with biogeochemical patterns at the sites. Based on phylogenetic and statistical analyses, clone libraries differed significantly among volcanic sites, indicating that they support distinct lithotrophic assemblages. Although some of the clone sequences were similar to known rbcL sequences, most were novel. Based on nucleotide diversity and average pairwise difference, a forested site and an 1894 lava flow were found to support the most diverse and least diverse lithotrophic populations, respectively. These indices of diversity were not correlated with rates of atmospheric CO and hydrogen uptake but were correlated with estimates of respiration and microbial biomass.

Two main clusters within Trypanosoma cruzi zymodeme 3 are defined by distinct regions of the ribosomal RNA cistron

Parasitology ◽  
2002 ◽  
Vol 124 (2) ◽  
pp. 177-184 ◽  
Author(s):  
M. B. A. MENDONÇA ◽  
N. S. NEHME ◽  
S. S. SANTOS ◽  
E. CUPOLILLO ◽  
N. VARGAS ◽  
...  
Keyword(s):  
Trypanosoma Cruzi ◽  
Ribosomal Rna ◽  
Southern Blotting ◽  
Pcr Amplification ◽  
Rrna Gene ◽  
Pcr Products ◽  
Phylogenetic Lineages ◽  
Definition Of ◽  
Ribosomal Cistron ◽  
Panstrongylus Geniculatus

Trypanosoma cruzi is currently classified into 2 major phylogenetic lineages, T. cruzi I and II, that correlate with the formerly described zymodeme 1 and 2, respectively. Another isoenzymic group (zymodeme 3–Z3) was also described. In this study, we analysed the genetic diversity among Z3 isolates of the Brazilian Amazon by restriction fragment length polymorphism of the intergenic transcribed spacers (ITSs) of the ribosomal RNA cistron and the size of the divergent domain D7 of the 24Sα rRNA gene. DNAs from 12 T. cruzi Z3 isolates obtained from humans (2), Panstrongylus geniculatus (1), and Rhodnius brethesi (9) were submitted to PCR amplification of the ITSs plus the 5·8S rDNA. The PCR products were digested with 4 distinct endonucleases and the profiles analysed by a numerical methodology. The phenetic dendrogram revealed a clear dichotomy in the Z3 group, defining 2 groups that were named Z3-A and Z3-B. Dimorphism was also found in the band sizes of the amplified D7 divergent domain of the 24Sα rDNA, which showed a perfect correlation with the ITSs clustering. The organization of the ribosomal cistron was investigated by Southern blotting and shown to be conserved in the genome of the 2 Z3 groups. This study shows that the rDNA cistron allows the definition of 2 distinct subclusters in Z3 isolates.

scholarly journals Length polymorphisms of simple sequence repeat DNA in soybean.

Genetics ◽  
1992 ◽  
Vol 132 (4) ◽  
pp. 1131-1139 ◽  
Author(s):  
M S Akkaya ◽  
A A Bhagwat ◽  
P B Cregan
Keyword(s):  
Genetic Markers ◽  
Simple Sequence Repeat ◽  
Pcr Amplification ◽  
Pcr Primers ◽  
F1 Hybrids ◽  
Sequence Repeat ◽  
Pcr Products ◽  
Soybean Genotypes ◽  
Ssr Loci ◽  
Simple Sequence

Abstract The objective of this work was to ascertain the presence and degree of simple sequence repeat (SSR) DNA length polymorphism in the soybean [Glycine max (L.) Merr.]. A search of GenBank revealed no (CA)n or (GT)n SSRs with n greater than 8 in soybean. In contrast, 5 (AT)n and 1 (ATT)n SSRs with n ranging from 14 to 27 were detected. Polymerase chain reaction (PCR) primers to regions flanking the six SSR loci were used in PCR amplification of DNA from 43 homozygous soybean genotypes. At three loci, amplification produced one PCR product per genotype and revealed 6, 7 and 8 product length variants (alleles) at the three loci, respectively. F1 hybrids between parents carrying different alleles produced two PCR products identical to the two parents. Codominant segregation of alleles among F2 progeny was demonstrated at each locus. A soybean DNA library was screened for the presence of (CA/GT)n SSRs. Sequencing of positive clones revealed that the longest such SSR was (CA)9. Thus, (CA)n SSRs with n of 15 or more are apparently much less common in soybean than in the human genome. In contrast to humans, (CA)n SSRs will probably not provide an abundant source of genetic markers in soybean. However, the apparent abundance of long (AT)n sequences should allow this SSR to serve as a source of highly polymorphic genetic markers in soybean.

scholarly journals Molecular and Culture-Based Analyses of Aerobic Carbon Monoxide Oxidizer Diversity†

2003 ◽  
Vol 69 (12) ◽  
pp. 7257-7265 ◽  
Author(s):  
Gary M. King
Keyword(s):  
Carbon Monoxide ◽  
Bradyrhizobium Japonicum ◽  
Large Subunit ◽  
Terrestrial Plants ◽  
Co Dehydrogenase ◽  
Mesorhizobium Loti ◽  
Pcr Products ◽  
Pcr Assays ◽  
High Degree ◽  
First Time

ABSTRACT Isolates belonging to six genera not previously known to oxidize CO were obtained from enrichments with aquatic and terrestrial plants. DNA from these and other isolates was used in PCR assays of the gene for the large subunit of carbon monoxide dehydrogenase (coxL). CoxL and putative coxL fragments were amplified from known CO oxidizers (e.g., Oligotropha carboxidovorans and Bradyrhizobium japonicum), from novel CO-oxidizing isolates (e.g., Aminobacter sp. strain COX, Burkholderia sp. strain LUP, Mesorhizobium sp. strain NMB1, Stappia strains M4 and M8, Stenotrophomonas sp. strain LUP, and Xanthobacter sp. strain COX), and from several well-known isolates for which the capacity to oxidize CO is reported here for the first time (e.g., Burkholderia fungorum LB400, Mesorhizobium loti, Stappia stellulata, and Stappia aggregata). PCR products from several taxa, e.g., O. carboxidovorans, B. japonicum, and B. fungorum, yielded sequences with a high degree (>99.6%) of identity to those in GenBank or genome databases. Aligned sequences formed two phylogenetically distinct groups. Group OMP contained sequences from previously known CO oxidizers, including O. carboxidovorans and Pseudomonas thermocarboxydovorans, plus a number of closely related sequences. Group BMS was dominated by putative coxL sequences from genera in the Rhizobiaceae and otherα -Proteobacteria. PCR analyses revealed that many CO oxidizers contained two coxL sequences, one from each group. CO oxidation by M. loti, for which whole-genome sequencing has revealed a single BMS-group putative coxL gene, strongly supports the notion that BMS sequences represent functional CO dehydrogenase proteins that are related to but distinct from previously characterized aerobic CO dehydrogenases.

scholarly journals Genome size and microsatellites: the effect of nuclear size on amplification potential

Genome ◽  
2002 ◽  
Vol 45 (1) ◽  
pp. 212-215 ◽  
Author(s):  
Trenton WJ Garner
Keyword(s):  
Genome Size ◽  
Microsatellite Dna ◽  
Pcr Amplification ◽  
Pcr Primers ◽  
Amplification Success ◽  
Pcr Products ◽  
Negative Effect ◽  
C Value ◽  
Primer Sets ◽  
Using Data

Although the frequency of microsatellite DNA regions generally increases with increasing genome size, genome size has a negative effect on polymerase chain reaction (PCR) amplification. Thus, researchers developing sets of PCR primers, as is commonly done for microsatellite DNA regions, may encounter greater difficulty when working with species that have larger genomes. I investigated the effect of genome size on overall amplification success using data from nine different metazoan taxa. The proportion of primer sets that did not amplify PCR products was strongly and positively correlated with the haploid C value of the target species. Increasing genome size may affect amplification success negatively because of a decrease in target:nontarget DNA or by dilution of the available primer pool by nonspecific binding.Key words: microsatellites, genome size, amplification success.

scholarly journals Quantification of Burkholderia coxL Genes in Hawaiian Volcanic Deposits

2010 ◽  
Vol 76 (7) ◽  
pp. 2212-2217 ◽  
Author(s):  
C. F. Weber ◽  
G. M. King
Keyword(s):  
Carbon Monoxide ◽  
16S Rrna ◽  
16S Rrna Gene ◽  
Large Subunit ◽  
Dry Weight ◽  
Gene Copy ◽  
Rrna Gene ◽  
Copy Numbers ◽  
Volcanic Deposits ◽  
Gene Copy Numbers

ABSTRACT Isolation of multiple carbon monoxide (CO)-oxidizing Burkholderia strains and detection by culture-independent approaches suggest that Burkholderia may be an important component of CO-oxidizing communities in Hawaiian volcanic deposits. The absolute and relative abundance of the bacteria in these communities remains unknown, however. In this study, a quantitative PCR (Q-PCR) approach has been developed to enumerate Burkholderia coxL genes (large subunit of carbon monoxide dehydrogenase). This represents the first attempt to enumerate coxL genes from CO oxidizers in environmental samples. coxL copy numbers have been determined for samples from three sites representing a vegetation gradient on a 1959 volcanic deposit that included unvegetated cinders (bare), edges of vegetated sites (edge), and sites within tree stands (canopy). Q-PCR has also been used to estimate copy numbers of Betaproteobacteria 16S rRNA gene copy numbers and total Bacteria 16S rRNA. coxL genes could not be detected in the bare site (detection limit, ≥4.7 � 103 copies per reaction) but average 1.0 � 108 � 2.4 � 107 and 8.6 � 108 � 7.6 �107 copies g−1 (dry weight) in edge and canopy sites, respectively, which differ statistically (P = 0.0007). Average Burkholderia coxL gene copy numbers, expressed as a percentage of total Bacteria 16S rRNA gene copy numbers, are 6.2 and 0.7% for the edge and canopy sites, respectively. Although the percentage of Burkholderia coxL is lower in the canopy site, significantly greater gene copy numbers demonstrate that absolute abundance of coxL increases in vegetated sites and contributes to the expansion of CO oxidizer communities during biological succession on volcanic deposits.

scholarly journals Diversity of Basidiomycetes in Michigan Agricultural Soils

2006 ◽  
Vol 72 (11) ◽  
pp. 7050-7056 ◽  
Author(s):  
Michael D. J. Lynch ◽  
R. Greg Thorn
Keyword(s):  
Agricultural Soils ◽  
Sequence Similarity ◽  
Large Subunit ◽  
Pcr Amplification ◽  
Soil Dna ◽  
Long Term Ecological Research ◽  
Pcr Products ◽  
Fungal Dna ◽  
Multiple Species ◽  
Almost All

ABSTRACT We analyzed the communities of soil basidiomycetes in agroecosystems that differ in tillage history at the Kellogg Biological Station Long-Term Ecological Research site near Battle Creek, Michigan. The approach combined soil DNA extraction through a bead-beating method modified to increase recovery of fungal DNA, PCR amplification with basidiomycete-specific primers, cloning and restriction fragment length polymorphism screening of mixed PCR products, and sequencing of unique clones. Much greater diversity was detected than was anticipated in this habitat on the basis of culture-based methods or surveys of fruiting bodies. With “species” defined as organisms yielding PCR products with ≥99% identity in the 5′ 650 bases of the nuclear large-subunit ribosomal DNA, 241 “species” were detected among 409 unique basidiomycete sequences recovered. Almost all major clades of basidiomycetes from basidiomycetous yeasts and other heterobasidiomycetes through polypores and euagarics (gilled mushrooms and relatives) were represented, with a majority from the latter clade. Only 24 of 241 “species” had 99% or greater sequence similarity to named reference sequences in GenBank, and several clades with multiple “species” could not be identified at the genus level by phylogenetic comparisons with named sequences. The total estimated “species” richness for this 11.2-ha site was 367 “species” of basidiomycetes. Since >99% of the study area has not been sampled, the accuracy of our diversity estimate is uncertain. Replication in time and space is required to detect additional diversity and the underlying community structure.

In Situ, Real-Time Catabolic Gene Expression: Extraction and Characterization of Naphthalene Dioxygenase mRNA Transcripts from Groundwater

1999 ◽  
Vol 65 (1) ◽  
pp. 80-87 ◽  
Author(s):  
Mark S. Wilson ◽  
Corien Bakermans ◽  
Eugene L. Madsen
Keyword(s):  
Coal Tar ◽  
Sodium Dodecyl ◽  
Pcr Amplification ◽  
Pcr Primers ◽  
Contaminated Site ◽  
Sequence Comparisons ◽  
Degrading Bacteria ◽  
Genes Encoding ◽  
Pcr Products

ABSTRACT We developed procedures for isolating and characterizing in situ-transcribed mRNA from groundwater microorganisms catabolizing naphthalene at a coal tar waste-contaminated site. Groundwater was pumped through 0.22-μm-pore-size filters, which were then frozen in dry ice-ethanol. RNA was extracted from the frozen filters by boiling sodium dodecyl sulfate lysis and acidic phenol-chloroform extraction. Transcript characterization was performed with a series of PCR primers designed to amplify nahAc homologs. Several primer pairs were found to amplify nahAc homologs representing the entire diversity of the naphthalene-degrading genes. The environmental RNA extract was reverse transcribed, and the resultant mixture of cDNAs was amplified by PCR. A digoxigenin-labeled probe mixture was produced by PCR amplification of groundwater cDNA. This probe mixture hybridized under stringent conditions with the corresponding PCR products from naphthalene-degrading bacteria carrying a variety of nahAchomologs, indicating that diverse dioxygenase transcripts had been retrieved from groundwater. Diluted and undiluted cDNA preparations were independently amplified, and 28 of the resulting PCR products were cloned and sequenced. Sequence comparisons revealed two major groups related to the dioxygenase genes ndoB anddntAc, previously cloned from Pseudomonas putida NCIB 9816-4 and Burkholderia sp. strain DNT, respectively. A distinctive subgroup of sequences was found only in experiments performed with the undiluted cDNA preparation. To our knowledge, these results are the first to directly document in situ transcription of genes encoding naphthalene catabolism at a contaminated site by indigenous microorganisms. The retrieved sequences represent greater diversity than has been detected at the study site by culture-based approaches.

scholarly journals New Arsenite Oxidase Gene (aioA) PCR Primers for Assessing Arsenite-Oxidizer Diversity in the Environment Using High-Throughput Sequencing

2021 ◽  
Vol 12 ◽  
Author(s):  
Min Hu ◽  
Fangbai Li ◽  
Jiangtao Qiao ◽  
Chaolei Yuan ◽  
Huanyun Yu ◽  
...  
Keyword(s):  
High Throughput ◽  
Sanger Sequencing ◽  
High Throughput Sequencing ◽  
Large Subunit ◽  
Amplicon Sequencing ◽  
Pcr Primers ◽  
Taxonomic Composition ◽  
Natural Environments ◽  
Clone Libraries ◽  
Oxidase Gene

Gene encoding the large subunit of As(III) oxidase (AioA), an important component of the microbial As(III) oxidation system, is a widely used biomarker to characterize As(III)-oxidizing communities in the environment. However, many studies were restricted to a few sequences generated by clone libraries and Sanger sequencing, which may have underestimated the diversity of As(III)-oxidizers in natural environments. In this study, we designed a primer pair, 1109F (5′-ATC TGG GGB AAY RAC AAY TA−3′) and 1548R (5′-TTC ATB GAS GTS AGR TTC AT−3′), targeting gene sequence encoding for the conserved molybdopterin center of the AioA protein, yielding amplicons approximately 450 bp in size that are feasible for highly parallel amplicon sequencing. By utilizing in silico analyses and the experimental construction of clone libraries using Sanger sequencing, the specificity and resolution of 1109F/1548R are approximated with two other previously published and commonly used primers, i.e., M1-2F/M3-2R and deg1F/deg1R. With the use of the 1109F/1548R primer pair, the taxonomic composition of the aioA genes was similar both according to the Sanger and next-generation sequencing (NGS) platforms. Furthermore, high-throughput amplicon sequencing using the primer pair, 1109F/1548R, successfully identified the well-known As(III)-oxidizers in paddy soils and sediments, and they also revealed the differences in the community structure and composition of As(III)-oxidizers in above two biotopes. The random forest analysis showed that the dissolved As(III) had the highest relative influence on the Chao1 index of the aioA genes. These observations demonstrate that the newly designed PCR primers enhanced the ability to detect the diversity of aioA-encoding microorganisms in environments using highly parallel short amplicon sequencing.

Sign in / Sign up

Export Citation Format

Share Document