Evaluation of DNA Extraction and Purification Methods for Corn Straw Biogas Slurry

2013 ◽  
Vol 773 ◽  
pp. 113-117
Author(s):  
Jiang Tao Qiao ◽  
Rong Bo Guo ◽  
Xiao Shuang Shi ◽  
Yan Ling Qiu

Corn straw biogas slurry always contains humic substances, which poses particular challenges in obtaining PCR-amplifiable DNA for analysis of microbial community. To establish an efficient and reliable DNA extraction method for straw biogas slurry, four approaches: i.e., direct SDS-based method, direct bead-based method, indirect SDS-based method, and indirect bead-based method were evaluated by comparing DNA yield, humic acid contamination, PCR amplifiability, and restriction fragment length polymorphisms (RFLP) of amplified 16S rRNA genes. Direct DNA extraction methods yielded 3-fold higher amounts of DNA than indirect procedures, but its DNA purity was lower. The A260/A230 ratio of DNA from indirect methods (0.8-0.85) were higher than that of DNA from direct methods (0.5-0.6), indicating DNA from direct methods contained high levels of humate contamination. PCR amplification was successful with crude DNA from indirect methods, but not with crude DNA from direct methods. PCR products could also be obtained with purified DNA from direct bead-based method, whereas not direct SDS-based method. Among the four methods, direct bead-based method, indirect SDS-based method and indirect bead-based method could obtain high-quality DNA extracts from corn straw biogas slurry. RFLP analysis further demonstrated the restriction patterns of amplified 16S rRNA genes from three methods were relatively identical microbial diversity.

2012 ◽  
Vol 56 ◽  
pp. S266
Author(s):  
S. Krohn ◽  
J. Hartmann ◽  
A. Brodzinski ◽  
A. Chatzinotas ◽  
S. Bohm ◽  
...  

1999 ◽  
Vol 122 (2) ◽  
pp. 323-328 ◽  
Author(s):  
M. T. E. P. ALLSOPP ◽  
C. M. HATTINGH ◽  
S. W. VOGEL ◽  
B. A. ALLSOPP

A panel of 16S ribosomal RNA gene probes has been developed for the study of the epidemiology of heartwater; five of these detect different cowdria genotypes, one detects five distinct genotypes; one detects any Group III Ehrlichia species other than Cowdria and one detects any Group II Ehrlichia species. These probes have been used on PCR-amplified rickettsial 16S rRNA genes from over 200 Amblyomma hebraeum ticks. Control ticks were laboratory-reared and either uninfected or fed on sheep experimentally infected with different cowdria isolates, field ticks were collected from animals in heartwater-endemic areas. All tick-derived DNA samples were also examined by PCR amplification and probing for two other cowdria genes (map1 and pCS20) which have previously been used for heartwater epidemiology. This paper describes the first direct comparison of all currently available DNA probes for heartwater-associated organisms.


2004 ◽  
Vol 70 (3) ◽  
pp. 1787-1794 ◽  
Author(s):  
Vanessa M. Conn ◽  
Christopher M. M. Franco

ABSTRACT The endophytic actinobacterial population in the roots of wheat grown in three different soils obtained from the southeast part of South Australia was investigated by terminal restriction fragment length polymorphism (T-RFLP) analysis of the amplified 16S rRNA genes. A new, validated approach was applied to the T-RFLP analysis in order to estimate, to the genus level, the actinobacterial population that was identified. Actinobacterium-biased primers were used together with three restriction enzymes to obtain terminal restriction fragments (TRFs). The TRFs were matched to bacterial genera by the T-RFLP Analysis Program, and the data were analyzed to validate and semiquantify the genera present within the plant roots. The highest diversity and level of endophytic colonization were found in the roots of wheat grown in a dark loam from Swedes Flat, and the lowest were found in water-repellent sand from Western Flat. This molecular approach detected a greater diversity of actinobacteria than did previous culture-dependent methods, with the predominant genera being Mycobacterium (21.02%) in Swedes Flat, Streptomyces (14.35%) in Red Loam, and Kitasatospora (15.02%) in Western Flat. This study indicates that the soil that supported a higher number of indigenous organisms resulted in wheat roots with higher actinobacterial diversity and levels of colonization within the plant tissue. Sequencing of 16S rRNA clones, obtained using the same actinobacterium-biased PCR primers that were used in the T-RFLP analysis, confirmed the presence of the actinobacterial diversity and identified a number of Mycobacterium and Streptomyces species.


2002 ◽  
Vol 68 (10) ◽  
pp. 5064-5081 ◽  
Author(s):  
Alexander Loy ◽  
Angelika Lehner ◽  
Natuschka Lee ◽  
Justyna Adamczyk ◽  
Harald Meier ◽  
...  

ABSTRACT For cultivation-independent detection of sulfate-reducing prokaryotes (SRPs) an oligonucleotide microarray consisting of 132 16S rRNA gene-targeted oligonucleotide probes (18-mers) having hierarchical and parallel (identical) specificity for the detection of all known lineages of sulfate-reducing prokaryotes (SRP-PhyloChip) was designed and subsequently evaluated with 41 suitable pure cultures of SRPs. The applicability of SRP-PhyloChip for diversity screening of SRPs in environmental and clinical samples was tested by using samples from periodontal tooth pockets and from the chemocline of a hypersaline cyanobacterial mat from Solar Lake (Sinai, Egypt). Consistent with previous studies, SRP-PhyloChip indicated the occurrence of Desulfomicrobium spp. in the tooth pockets and the presence of Desulfonema- and Desulfomonile-like SRPs (together with other SRPs) in the chemocline of the mat. The SRP-PhyloChip results were confirmed by several DNA microarray-independent techniques, including specific PCR amplification, cloning, and sequencing of SRP 16S rRNA genes and the genes encoding the dissimilatory (bi)sulfite reductase (dsrAB).


2000 ◽  
Vol 66 (6) ◽  
pp. 2365-2371 ◽  
Author(s):  
E. Jurkevitch ◽  
D. Minz ◽  
Barak Ramati ◽  
Gili Barel

ABSTRACT Thirty new Bdellovibrio strains were isolated from an agricultural soil and from the rhizosphere of plants grown in that soil. Using a combined molecular and culture-based approach, we found that the soil bdellovibrios included subpopulations of organisms that differed from rhizosphere bdellovibrios. Thirteen soil and seven common bean rhizosphere Bdellovibrio strains were isolated when Pseudomonas corrugata was used as prey; seven and two soil strains were isolated when Erwinia carotovora subsp.carotovora and Agrobacterium tumefaciens, respectively, were used as prey; and one tomato rhizosphere strain was isolated when A. tumefaciens was used as prey. In soil and in the rhizosphere, depending on the prey cells used, the concentrations of bdellovibrios were between 3 × 102 to 6 × 103 and 2.8 × 102 to 2.3 × 104 PFU g−1. A prey range analysis of five soil and rhizosphereBdellovibrio isolates performed with 22 substrate species, most of which were plant-pathogenic and plant growth-enhancing bacteria, revealed unique utilization patterns and differences between closely related prey cells. An approximately 830-bp fragment of the 16S rRNA genes of all of theBdellovibrio strains used was obtained by PCR amplification by using a Bdellovibrio-specific primer combination. Soil and common bean rhizosphere strains produced two and one restriction patterns for this PCR product, respectively. The 16S rRNA genes of three soil isolates and three root-associated isolates were sequenced. One soil isolate belonged to theBdellovibrio stolpii-Bdellovibrio starrii clade, while all of the other isolates clustered withBdellovibrio bacteriovorus and formed two distantly related, heterogeneous groups.


2014 ◽  
Vol 2014 ◽  
pp. 1-10 ◽  
Author(s):  
Ingo C. Starke ◽  
Wilfried Vahjen ◽  
Robert Pieper ◽  
Jürgen Zentek

In this study, the effect of different DNA extraction procedures and primer sets on pyrosequencing results regarding the composition of bacterial communities in the ileum of piglets was investigated. Ileal chyme from piglets fed a diet containing different amounts of zinc oxide was used to evaluate a pyrosequencing study with barcoded 16S rRNA PCR products. Two DNA extraction methods (bead beating versus silica gel columns) and two primer sets targeting variable regions of bacterial 16S rRNA genes (8f-534r versus 968f-1401r) were considered. The SEED viewer software of the MG-RAST server was used for automated sequence analysis. A total of 5.2×105 sequences were used for analysis after processing for read length (150 bp), minimum sequence occurrence (5), and exclusion of eukaryotic and unclassified/uncultured sequences. DNA extraction procedures and primer sets differed significantly in total sequence yield. The distribution of bacterial order and main bacterial genera was influenced significantly by both parameters. However, this study has shown that the results of pyrosequencing studies using barcoded PCR amplicons of bacterial 16S rRNA genes depend on DNA extraction and primer choice, as well as on the manner of downstream sequence analysis.


2003 ◽  
Vol 69 (5) ◽  
pp. 2555-2562 ◽  
Author(s):  
Markus Egert ◽  
Michael W. Friedrich

ABSTRACT Terminal restriction fragment length polymorphism (T-RFLP) analysis of PCR-amplified genes is a widely used fingerprinting technique in molecular microbial ecology. In this study, we show that besides expected terminal restriction fragments (T-RFs), additional secondary T-RFs occur in T-RFLP analysis of amplicons from cloned 16S rRNA genes at high frequency. A total of 50% of 109 bacterial and 78% of 68 archaeal clones from the guts of cetoniid beetle larvae, using MspI and AluI as restriction enzymes, respectively, were affected by the presence of these additional T-RFs. These peaks were called “pseudo-T-RFs” since they can be detected as terminal fluorescently labeled fragments in T-RFLP analysis but do not represent the primary terminal restriction site as indicated by sequence data analysis. Pseudo-T-RFs were also identified in T-RFLP profiles of pure culture and environmental DNA extracts. Digestion of amplicons with the single-strand-specific mung bean nuclease prior to T-RFLP analysis completely eliminated pseudo-T-RFs. This clearly indicates that single-stranded amplicons are the reason for the formation of pseudo-T-RFs, most probably because single-stranded restriction sites cannot be cleaved by restriction enzymes. The strong dependence of pseudo-T-RF formation on the number of cycles used in PCR indicates that (partly) single-stranded amplicons can be formed during amplification of 16S rRNA genes. In a model, we explain how transiently formed secondary structures of single-stranded amplicons may render single-stranded amplicons accessible to restriction enzymes. The occurrence of pseudo-T-RFs has consequences for the interpretation of T-RFLP profiles from environmental samples, since pseudo-T-RFs may lead to an overestimation of microbial diversity. Therefore, it is advisable to establish 16S rRNA gene sequence clone libraries in parallel with T-RFLP analysis from the same sample and to check clones for their in vitro digestion T-RF pattern to facilitate the detection of pseudo-T-RFs.


2001 ◽  
Vol 67 (4) ◽  
pp. 1893-1901 ◽  
Author(s):  
Gesche Braker ◽  
Héctor L. Ayala-del-Rı́o ◽  
Allan H. Devol ◽  
Andreas Fesefeldt ◽  
James M. Tiedje

ABSTRACT Steep vertical gradients of oxidants (O2 and NO3 −) in Puget Sound and Washington continental margin sediments indicate that aerobic respiration and denitrification occur within the top few millimeters to centimeters. To systematically explore the underlying communities of denitrifiers,Bacteria, and Archaea along redox gradients at distant geographic locations, nitrite reductase (nirS) genes and bacterial and archaeal 16S rRNA genes (rDNAs) were PCR amplified and analyzed by terminal restriction fragment length polymorphism (T-RFLP) analysis. The suitablility of T-RFLP analysis for investigating communities of nirS-containing denitrifiers was established by the correspondence of dominant terminal restriction fragments (T-RFs) of nirS to computer-simulated T-RFs ofnirS clones. These clones belonged to clusters II, III, and IV from the same cores and were analyzed in a previous study (G. Braker, J. Zhou, L. Wu, A. H. Devol, and J. M. Tiedje, Appl. Environ. Microbiol. 66:2096–2104, 2000). T-RFLP analysis ofnirS and bacterial rDNA revealed a high level of functional and phylogenetic diversity, whereas the level of diversity ofArchaea was lower. A comparison of T-RFLPs based on the presence or absence of T-RFs and correspondence analysis based on the frequencies and heights of T-RFs allowed us to group sediment samples according to the sampling location and thus clearly distinguish Puget Sound and the Washington margin populations. However, changes in community structure within sediment core sections during the transition from aerobic to anaerobic conditions were minor. Thus, within the top layers of marine sediments, redox gradients seem to result from the differential metabolic activities of populations of similar communities, probably through mixing by marine invertebrates rather than from the development of distinct communities.


2000 ◽  
Vol 38 (11) ◽  
pp. 4193-4200 ◽  
Author(s):  
Chao-Chin Chang ◽  
Rickie W. Kasten ◽  
Bruno B. Chomel ◽  
Darren C. Simpson ◽  
Carrie M. Hew ◽  
...  

Bartonella vinsonii subsp. berkhoffii was originally isolated from a dog suffering infectious endocarditis and was recently identified as a zoonotic agent causing human endocarditis. Following the coyote bite of a child who developed clinical signs compatible with Bartonella infection in Santa Clara County, Calif., this epidemiological study was conducted. Among 109 coyotes (Canis latrans) from central coastal California, 31 animals (28%) were found to be bacteremic with B. vinsonii subsp.berkhoffii and 83 animals (76%) had B. vinsonii subsp. berkhoffii antibodies. These findings suggest these animals could be the wildlife reservoir of B. vinsonii subsp. berkhoffii. PCR-restriction fragment length polymorphism (PCR-RFLP) analysis of the gltA and 16S rRNA genes for these 31 isolates yielded similar profiles that were identical to those of B. vinsonii subsp.berkhoffii. Partial sequencing of the gltA and 16S rRNA genes, respectively, indicated 99.5 and 100% homology between the coyote isolate and B. vinsonii subsp.berkhoffii (ATCC 51672). PCR-RFLP analysis of the 16S-23S intergenic spacer region showed the existence of two different strain profiles, as has been reported in dogs. Six (19%) of 31Bartonella bacteremic coyotes exhibited the strain profile that was identified in the type strain of a canine endocarditis case (B. vinsonii subsp. berkhoffii ATCC 51672). The other 25 bacteremic coyotes were infected with a strain that was similar to the strains isolated from healthy dogs. Based on whole bacterial genome analysis by pulsed-field gel electrophoresis (PFGE) with SmaI restriction endonuclease, there was more diversity in fingerprints for the coyote isolates, which had at least 10 major variants compared to the two variants described for domestic dog isolates from the eastern United States. By PFGE analysis, threeBartonella bacteremic coyotes were infected by a strain identical to the one isolated from three healthy dog carriers. Further studies are necessary to elucidate the mode of transmission of B. vinsonii subsp. berkhoffii, especially to identify potential vectors, and to determine how humans become infected.


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