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1.
Use of Randomly Amplified Polymorphic DNA as a Means of Developing Genus- and Strain-Specific Streptomyces DNA Probes 总被引:1,自引:0,他引:1
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We have analyzed 20 randomly amplified polymorphic DNA (RAPD) primers against 36 Streptomyces strains, including 17 taxonomically undefined strains, 25 nonstreptomycete actinomycetes, and 12 outgroups consisting of gram-positive and -negative species. Most of the primers were useful in identifying unique DNA polymorphisms of all strains tested. We have used RAPD techniques to develop a genus-specific probe, one not necessarily targeting the ribosomal gene, for Streptomyces, and a strain-specific probe for the biological control agent Streptomyces lydicus WYEC108. In the course of these investigations, small-scale DNA isolations were also developed for efficiently isolating actinomycete DNA. Various modifications of isolation procedures for soil DNA were compared, and the reliability and specificity of the RAPD methodology were tested by specifically detecting the S. lydicus WYEC108 in DNA isolated from soil. 相似文献
2.
We have analyzed 20 randomly amplified polymorphic DNA (RAPD) primers against 36 Streptomyces strains, including 17 taxonomically undefined strains, 25 nonstreptomycete actinomycetes, and 12 outgroups consisting of gram-positive and -negative species. Most of the primers were useful in identifying unique DNA polymorphisms of all strains tested. We have used RAPD techniques to develop a genus-specific probe, one not necessarily targeting the ribosomal gene, for Streptomyces, and a strain-specific probe for the biological control agent Streptomyces lydicus WYEC108. In the course of these investigations, small-scale DNA isolations were also developed for efficiently isolating actinomycete DNA. Various modifications of isolation procedures for soil DNA were compared, and the reliability and specificity of the RAPD methodology were tested by specifically detecting the S. lydicus WYEC108 in DNA isolated from soil. 相似文献
3.
M. Siddique Awan Nabila Tabbasam N. Ayub M. E. Babar Mehboob-ur-Rahman Shahid Mahboob Rana M. I. Rajoka 《Molecular biology reports》2011,38(2):1367-1374
α- and β-Galactosidases find application in food processing, health and nutrition. Aspergillus niger is one of the potent producer of these enzymes and was genotypically improved using gamma-ray induced mutagenesis. The mutant-derivative
produced two-fold higher α- and β-galactosidases. For testing genetic variability and its relationship with phenotypic properties
of the two organisms, DNA samples of the mutant and parental strains of A. niger were amplified with 28 deca-nucleotide synthetic primers. RAPD analysis showed significantly different pattern between parental
and mutant cultures. The mutant derivative yielded homogeneous while parental strain formed heterogeneous amplification patterns.
Seven primers identified 42.9% polymorphism in the amplification products, indicating that these primers determined some genetic
variability between the two strains. Thus RAPD was found to be an efficient technique to determine genetic variability in
the mutant and wild organisms. Both wild and mutant strains were analyzed for their potential to produce galactosidases. Comparison
of different carbon sources on enzyme yield revealed that wheat bran is significant (P < 0.01) effective producer and economical source followed by rice bran, rice polishing and lactose. The mutant was significantly
better enzyme producer and could be considered for its prospective application in food, nutrition and health and that RAPD
can be effectively used to differentiate mutant strain from the parental strain based on the RAPD patterns. 相似文献
4.
Swedish soil isolates biochemically classified as Bacillus thuringiensis subsp. israelensis were further examined for genetic diversity by multilocus enzyme electrophoresis (MLEE), random amplified polymorphic DNA
analysis (RAPD), pulse field gel electrophoresis (PFGE), and Southern blotting, and were compared with reference strains.
All the tested strains belonging to the Bt. israelensis serotype H14 were found to be identical, as judged from the RAPD analysis. MLEE analysis gave a similar result; only one
H14 strain was found to differ from the remaining H14 strains by one null allele. PFGE analysis confirmed a very close relationship
between the H14 strains but revealed an SfiI restriction fragment of variable size. Southern blot analyses were carried out with probes for the chromosomally encoded
flagellin gene(s) and the plasmid-encoded mosquitocidal toxins. All probes gave similar hybridization patterns in the H14
strains. The mosquito toxin probes hybridized only to the H14 strains, except for one probe hybridizing to strain 6:3, which
was originally isolated from the same soil sample as strains 6:11 and 6:12. Because the RAPD, MLEE, and PFGE analyses showed
that strain 6:3 appears to be unrelated to strains 6:11 and 6:12, the presence of a mosquito toxin sequence in strain 6:3
may suggest that gene transfer has occurred.
Received: 8 July 1999 / Accepted: 9 August 1999 相似文献
5.
Chromosomal polymorphism and adaptation to specific industrial environments of Saccharomyces strains
Several industrial Saccharomyces strains, including bakers', wine, brewers' and distillers' yeasts, have been characterized with regards to their DNA content,
chromosomal polymorphism and homologies with the DNA of laboratory strains. Measurement of the DNA contents of cells suggested
that most of the industrial yeasts were aneuploids. Polymorphisms in the electrophoretic chromosomal pattern were so large
that each strain could be individually identified. However, no specific changes relating to a particular group were observed.
Hybridization using different probes from laboratory strains was very strong in all cases, indicating that all industrial
strains possess a high degree of DNA homology with laboratory yeasts. Probes URA3, CUP1, LEU2, TRP1, GAL4 or ADC1 demonstrated the presence of one or two bands, two especially in bakers' strains. Also, results indicate that all hybridized
genes are located on the same chromosomes both in laboratory and industrial strains. Translocation from chromosome VIII to
XVI seems to have occurred in a distillers' strain, judging by the location of the CUP1 probe. Finally, when the SUC2 probe is used, results indicate a very widespread presence of the SUC genes in only bakers' and molasses alcohol distillers' strains. This clearly suggests that amplification of SUC genes is an adaptive mechanism conferring better fitness upon the strains in their specific industrial conditions. The widespread
presence of Ty1 and Ty2 elements as well as Y′ subtelomeric sequences could account for the inter- and intrachromosomal changes detected.
Received: 21 July 1997 / Accepted: 25 August 1997 相似文献
6.
G. P. Gill C. F. Harvey R. C. Gardner L. G. Fraser 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1998,97(3):439-445
Two sex-linked random amplified polymorphic DNA (RAPD) markers identified from Actinidia chinensis were converted into sequence-characterised amplified regions (SCARs) for the large-scale screening of Actinidia breeding populations. Initial SCAR primers converted one RAPD (SmX) into a dominant marker, but the other (SmY), which was
potentially more useful because of its linkage to the male determining ‘Y’ locus, failed to retain polymorphism. This difficulty
was overcome by cloning and sequencing the alternate ‘allele’ from female plants, and then designing ‘allele’-specific primers
that utilised nucleotide differences between the sexes. Using a quick squash-blot method of DNA extraction, the SCAR primers
were tested in 120 A. chinensis plants to determine their gender. The system is now in use for large-scale screening of seedling populations in the Actinidia breeding programme. The sex-linked SCAR primers also functioned with plants from some other geographically separate accessions
of A. chinensis and with plants in the closely related polyploid species A. deliciosa, but did not amplify a sex-linked band in more distantly related species of Actinidia.
Received: 27 December 1997 / Accepted: 5 March 1998 相似文献
7.
V. R. Bommineni P. P. Jauhar T. S. Peterson R. N. Chibbar A. B. Almouslem 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1997,95(5-6):757-763
The objective of this study was to detect the presence of alien chromatin in intergeneric hybrids of durum wheat (Triticum turgidum, 2n=4x=28; AABB genomes) with the perennial grass Thinopyrum junceiforme (2n=4x=28; J1J1J2J2) using RAPD markers. The first step was to identify amplification of species-specific DNA markers in the parental grass species
and durum wheat cultivars. Initially, the genomic DNA of five grass species (Thinopyrum junceiforme, Th. bessarabicum, Lophopyrum elongatum, Leymus karataviensis and Elytrigia pycnantha) and selected durum cultivars (‘Langdon’, ‘Durox’, ‘Lloyd’, ‘Monroe’, and ‘Medora’) was screened with 40 oligonucleotide
primers (nano-mers). Three oligonucleotides that amplified DNA fragments specific to a grass species or to a durum cultivar
were identified. Primer PR21 amplified DNA fragments specific to each of the five durum cultivars, and primers PR22 and PR23
amplified fragments specific to each of the grass species. Intergeneric hybrids between the durum cultivars ‘Langdon’, ‘Lloyd’
and ‘Durox’ and Th. junceiforme, and their backcross (BC) progeny were screened with all 40 primers. Six primers amplified parent-specific DNA fragments
in the F1 hybrids and their BC1 progeny. Three primers, PR22, PR23 and PR41, that amplified Th. junceiforme DNA fragments in both F1 and BC1 were further analyzed. The presence of an amplified 1.7-kb Th. junceiforme DNA fragment in the F1 hybrids and BC1 progeny was confirmed using Southern analysis by hybridization with both Th. junceiforme genomic DNA and Th. junceiforme DNA amplified with primer PR41. With the exception of line BC1F2 no. 5, five selfed progeny of BC1 and a BC2 of line 3 (BC1F2 no. 3בLloyd’) from a cross of ‘Lloyd’×Th. junceiforme showed the presence of the 1.7-kb DNA fragment. All selfed BC1 and BC2 lines retained the 600-bp fragment that was confirmed after hybridization with Th. junceiforme DNA amplified with primer PR22. Other experiments using RFLP markers also showed the presence of up to seven Th. junceiforme DNA fragments in the F1 hybrids and their BC progeny after hybridization with Th. junceiforme DNA amplified with primer PR41. These studies show the usefulness of molecular markers in detecting alien chromatin/DNA fragments
in intergeneric hybrids with durum wheat.
Received: 21 November 1996 / Accepted: 21 March 1997 相似文献
8.
The strain ZK7 of Pochonia chlamydosporia var. chlamydosporia and IPC of Paecilomyces lilacinus are highly effective in the biological control against root-knot nematodes infecting tobacco. When applied, they require
a specific monitoring method to evaluate the colonization and dispersal in soil. In this work, the randomly amplified polymorphic
DNA (RAPD) technique was used to differentiate between the two individual strains and 95 other isolates, including isolates
of the same species and common soil fungi. This approach allowed the selection of specific fragments of 1.2 kb (Vc1200) and
2.0 kb (Vc2000) specific for ZK7, 1.4 kb (P1400) and 0.85 kb (P850) specific for IPC, using the random Primers OPL-02, OPD-05,
OPD-05 and OPC-11, respectively. These fragments were cloned, sequenced, and used to design sequence-characterized amplification
region (SCAR) primers specific for the two strains. In classical polymerase chain reaction (PCR), with serial dilution of
ZK7 and IPC pure culture DNAs template, the detection limits of these oligonucleotide SCAR-PCR primers were found to be 10,
1000, 500, 100 pg, respectively. In the dot blotting, digoxigenin (DIG)-labeled amplicons from these four primers specifically
recognized the corresponding fragments in the DNAs template of these two strains. The detection limit of these amplicons were
0.2, 0.2, 0.5, 0.5 μg, respectively. 相似文献
9.
The application of random amplified polymorphic DNA (RAPD) analysis for the identifcation of ectomycorrhizal symbionts of
spruce (Picea abies) belonging to the genera Boletus, Amanita and Lactarius at and below the species level was investigated. Using both fingerprinting [M13, (GTG)5, (GACA)4] as well as random oligonucleotide primers (V1 and V5), a high degree of variability of amplified DNA fragments (band-sharing
index 65–80%) was detected between different strains of the same species, hence enabling the identification of individual
strains within the same species. The band-sharing index between different species of the same genus (Boletus, Russula and Amanita) was in the range of 20–30%, and similar values were obtained when strains from different taxa were compared. Thus RAPD is
too sensitive at this level of relatonship and cannot be used to align an unknown symbiont to a given taxon. We therefore
conclude that RAPD is a promising tool for the identification of individual strains, and could thus be used to distinguish
indigenous and introduced mycorrhizal strains from the same species in natural ecosystems.
Accepted: 29 August 1995 相似文献
10.
Sheng-Ping L. Hwang Shing Kou Wang Su Fen Wei Li-Chuan Cheng Jeng Chang 《Marine biotechnology (New York, N.Y.)》1999,1(2):200-206
To investigate the potential of DNA polymerase α as a marker for DNA replication in phytoplankton, two gene fragments that
showed a high degree of similarity with eukaryotic DNA polymerase α were cloned from two strains of a diatom, Skeletonema costatum (Greville) Cleve. The gene fragments amplified with the polymerase chain reaction were 397 and 396 bp in length, respectively.
The deduced amino acid sequences showed 44% to 61% similarity to the corresponding regions of DNA polymerase α sequences of
eukaryotic organisms ranging from yeast to humans. The similarity was especially high in three evolutionarily conserved regions
within the amplified fragments. Further, hybridization patterns from Southern blotting confirmed that the amplified fragments
were an integral part on the genome of S. costatum. In batch cultures abundant messenger of DNA polymerase α appeared in the late exponential phase and the early stationary
phase. This pattern suggests that DNA polymerase α expression is associated with actively dividing cells.
Received October 27, 1998; accepted November 13, 1998. 相似文献
11.
Cell-surface lectins were screened in seven strains of Azospirillum brasilense and A. lipoferum. The presence of lectins was determined by particle agglutination assays employing latex beads coated with neoglycoproteins
and by Western blot with neoglycoproteins labeled with horseradish peroxidase as a probe. Seven strains were agglutinated
with the assayed sugar residues. The highest agglutination was with fucose and glucose and to a lesser extent with mannose
residues. Cell-wall proteins extracted from two Azospirillum spp. strains exhibit lectin-like activities. We believe that lectins are present in the cell-wall of Azospirillum spp.
Received: 23 June 1997 / Accepted: 23 September 1997 相似文献
12.
A collection of 32 lactococcal strains isolated from raw milk in the Camembert RDO (registered designation of origin) area
were phenotypically and genotypically characterized. As expected for environmental isolates, all strains had a Lactococcus lactis subsp. lactis phenotype. The strains were then genotypically identified by the randomly amplified polymorphic DNA (RAPD) technique, using
reference strains of lactococci. Two major clusters were identified containing the two subspecies lactis and cremoris. The subspecies lactis cluster could be divided into five subgroups whereas there was a high coefficient of similarity between all strains in the
subspecies cremoris cluster. This RAPD classification was then compared with that of a traditional PCR assay using L.lactis species-specific primers corresponding to part of the histidine biosynthesis operon. The two subspecies were differentiated
by the size of the fragment amplified (about 200 bp longer for subspecies cremoris). Unlike preliminary phenotypic assignments, the results of PCR experiments corroborated the genotypic identification of
the lactococcal strains by RAPD allowing the technique to be reconsidered on the basis of its taxonomic efficiency.
Received: 14 May 1998 / Accepted: 3 September 1998 相似文献
13.
A total of 10 non-repetitive multi-drug-resistant Acinetobacter strains were collected. With reference to A. calcoaceticus (ATCC23055), A. baumannii (ATCC19606), A. lwoffii (ATCC17986), and A. junii (NCTC5866),DNA fingerprint technique, amplified ribosomal DNA restriction analysis (ARDRA), and random amplified polymorphism
DNA (RAPD) were carried out to identify the genomic species of Acinetobacter spp. The distances between them were calculated by the unweighted pair group method with arithmetic (UPGMA). Genotypes of
Acinetobacter spp. were effectively classified and an A. junii together with nine A. baumannii isolates was genomically identified. The combination of ARDRA and RAPD DNA-fingerprint technique shows high complementarity,
and could be a useful tool in Acinetobacter genomic species identification.
__________
Translated from Microbiology, 2007, 34(2): 303–306 [译自:微生物学通报] 相似文献
14.
Strain identification in situ is an important factor in the monitoring of microorganisms used in the field. In this study, we demonstrated the use of sequence-characterized amplified region (SCAR) markers to detect genomic DNA from Trichoderma harzianum 2413 from soil. Two primers (SCAR A1/SCAR A1c) were tested against DNA of 27 isolates of Trichoderma spp. and amplified a 990-bp fragment from T. atroviride 11 and a 1.5-kb fragment from T. harzianum 2413, using an annealing temperature of 68°C. These fragments showed no significant homology to any sequence deposited in the databases. The primer pair, BR1 and BR2, was designed to the 1.5-kb fragment amplified from T. harzianum 2413, generating a SCAR marker. To test the specificity of these primers, experiments were conducted using the DNA from 27 Trichoderma spp. strains and 22 field soil samples obtained from four different countries. PCR results showed that BR1 and BR2 amplified an 837-bp fragment unique to T. harzianum 2413. Assays in which total DNA was extracted from sterile and nonsterile soil samples, inoculated with spore or mycelium combinations of Trichoderma spp. strains, indicated that the BR1 and BR2 primers could specifically detect T. harzianum 2413 in a pool of mixed DNA. No other soil-microorganisms containing these sequences were amplified using these primers. To test whether the 837-bp SCAR marker of T. harzianum 2413 could be used in real-time PCR experiments, new primers (Q2413f and Q2413r) conjugated with a TaqMan fluorogenic probe were designed. Real-time PCR assays were applied using DNA from sterile and nonsterile soil samples inoculated with a known quantity of spores of Trichoderma spp. strains. 相似文献
15.
Strain-Specific Identification of Probiotic Lactobacillus rhamnosus with Randomly Amplified Polymorphic DNA-Derived PCR Primers 总被引:3,自引:0,他引:3
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In the present work, strain-specific PCR primers for Lactobacillus rhamnosus Lc 1/3 are described. The randomly amplified polymorphic DNA (RAPD) technique was used to produce potential strain-specific markers. They were screened for specificity by hybridization with DNA from 11 L. rhamnosus strains. A 613-bp RAPD marker found to be strain-specific was sequenced, and a primer pair specific to L. rhamnosus Lc 1/3 was constructed based on the sequence. The primer pair was tested with 11 Lactobacillus species and 11 L. rhamnosus strains and was found to be strain specific. The nucleotide sequence of the specific RAPD marker was found to contain part of a protein encoding region which showed significant similarity to several transposases for insertion sequence elements of various bacteria, including other lactic acid bacterium species. 相似文献
16.
We searched for sex-specific DNA sequences in the male and female genomes of African catfish, Clarias gariepinus (Burchell, 1822) by comparative random amplified polymorphic DNA (RAPD) assays performed on pooled DNA samples. Two sex-linked
RAPD markers were identified from the male DNA pool and confirmed on individual samples, showing good agreement with phenotypic
sex. Both markers were isolated, cloned and characterized. The first marker (CgaY1) was nearly 2.6 kb long, while the length
of second one (CgaY2) was 458 bp. Southern blot analysis with a CgaY1 probe showed strong hybridizing fragments only in males
and not in females under stringent conditions, indicating the presence of multiple copies of CgaY1 in the male genome. When
tested by zoo blot on the genomes of two closely related species from the Clariidae family, CgaY1 hybridized to the DNA of Heterobranchus longifilis and generated a faint male-specific band at low stringency. CgaY2 produced similar hybridization pattern in both sexes of
C. gariepinus, C. macrocephalus and H. longifilis. Specific primers were designed to the sequences and the markers were amplified in multiplex PCR reactions together with
a control band common to all individuals. This allowed for rapid, molecular sexing of the species on the basis of a simple
three band (male) versus one band (female) pattern. According to our knowledge these are the first sex-specific DNA markers
isolated from a siluroid fish species.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
17.
Development of RAPD and SCAR markers linked to the Russian wheat aphid resistance gene Dn2 in wheat 总被引:5,自引:0,他引:5
A. A. Myburg M. Cawood B. D. Wingfield A.-M. Botha 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1998,96(8):1162-1169
RAPD (random amplified polymorphic DNA) analysis was used to identify molecular markers linked to the Dn2 gene conferring resistance to the Russian wheat aphid (Diuraphis noxia Mordvilko). A set of near-isogenic lines (NILs) was screened with 300 RAPD primers for polymorphisms linked to the Dn2 gene. A total of 2700 RAPD loci were screened for linkage to the resistance locus. Four polymorphic RAPD fragments, two in
coupling phase and two in repulsion phase, were identified as putative RAPD markers for the Dn2 gene. Segregation analysis of these markers in an F2 population segregating for the resistance gene revealed that all four markers were closely linked to the Dn2 locus. Linkage distances ranged from 3.3 cM to 4.4 cM. Southern analysis of the RAPD products using the cloned RAPD markers
as probes confirmed the homology of the RAPD amplification products. The coupling-phase marker OPB10880c and the repulsion-phase marker OPN1400r were converted to sequence characterized amplified region (SCAR) markers. SCAR analysis of the F2 population and other resistant and susceptible South African wheat cultivars corroborated the observed linkage of the RAPD
markers to the Dn2 resistance locus. These markers will be useful for marker-assisted selection of the Dn2 gene for resistance breeding and gene pyramiding.
Received: 1 July 1997 / Accepted: 20 October 1997 相似文献
18.
An Agrobacterium vitis-specific DNA fragment (pAVS3) was generated from PCR polymorphic bands amplified by primer URP 2R. A. vitis specificity of this fragment was confirmed by Southern hybridization with genomic DNA from different Agrobacterium species. Sequence-characterized amplified region (SCAR) markers were developed for A. vitis specific detection, using 24-mer oligonucleotide primers designed from the flanking ends of the 670 bp insert in pAVS3. The SCAR primers amplified target sequences only from A. vitis strains and not from other Agrobacterium species or other bacterial genera. First round PCR detected bacterial cells between 5×102 and 1×103 cfu/ml and the detection sensitivity was increased to as few as 2 cfu/ml by nested PCR. This PCR protocol can be used to confirm the potential presence of infectious A. vitis strains in soil and furthermore, can identify A. vitis strains from naturally infected crown galls. 相似文献
19.
“Candidatus Liberobacter,” the uncultured bacterium associated with citrus Huanglongbing (HLB) disease, is an α-Proteobacteria, and two species, “Candidatus L. africanum” and “Candidatus L. asiaticum,” have been characterized by sequence analysis of the 16S rDNA and β operon (rplKAJL-rpoBC) genes. These genes were isolated by PCR and random cloning of DNA from infected plants. However, this strategy is laborious
and allowed selection of only three Liberobacter DNA fragments. In this paper, we described isolation of additional genes
using Random Amplified Polymorphic DNA (RAPD). In total, 102 random 10-mer primers were used in PCR reactions on healthy and
Liberobacter-infected plant DNA. Eight DNA bands amplified from infected plant DNA were cloned and analyzed. Six of them were
found to be part of the Liberobacter genome by sequence and hybridization experiments. On these DNA fragments, four genes
were identified: nusG, pgm, omp, and a hypothetical protein gene. These results indicate that RAPD can be used to clone DNA of uncultured organisms.
Received: 14 September 1998 / Accepted: 6 October 1998 相似文献
20.
T Cox C Frazier J Tuttle S Flood L Yagi C T Yamashiro R Behari C Paszko R J Cano 《Journal of industrial microbiology & biotechnology》1998,21(3):167-174
The presence of Listeria monocytogenes as a dairy food contaminant is a lethal threat to dairy industrialists; therefore, products tainted with L. monocytogenes must be quickly detected and removed from production. This fluorogenic PCR-based assay was developed to rapidly detect L. monocytogenes contamination in dairy samples before a final product is distributed. The detection method employed uses a PCR primer pair
and a fluorogenic TaqMan probe which bind to a region of a virulence determinant gene specific to L. monocytogenes. As the DNA target is amplified, the 5′ nuclease activity of Taq DNA polymerase hydrolyzes the internal fluorogenic probe creating a change in fluorescence that can be monitored and automatically
analyzed with a fluorometer. Sensitivity studies indicated a lower detection limit of under 10 CFU for pure culture extracts
and spiked dairy enrichments. A study was performed on 266 dairy product samples obtained from Central California dairy production
plants. Eighty-three of these samples were artificially spiked with both high and low concentrations of L. monocytogenes before an overnight enrichment in TSB/LiCl/colostin sulfate/moxalactam media. DNA from enriched samples was obtained using
a rapid Chelex extraction specifically designed for dairy sample enrichments and automated analysis. The extraction was followed
by the fluorogenic PCR assay and measurement of fluorescence increase. The assay was completed within 24 h, with an observed
95.2% sensitivity, 96.7% specificity, 92.9% positive predictive value, 97.8% negative predictive value, and 96.2% accuracy.
According to specificity studies, five other bacterial species cross-reacted with the fluorogenic 5′ nuclease PCR. However,
only one of these strains (Listeria grayi) was able to grow in the enrichment medium employed, and was not isolated from any of the 266 dairy product enrichments evaluated
in this study. Therefore, this method provides a rapid, sensitive, and automatable analysis alternative to standard culture
techniques for the detection of Listeria monocytogenes in dairy samples.
Received 4 February 1998/ Accepted in revised form 1 October 1998 相似文献