• International Journal of Oral Biology
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• 제46권4호
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• pp.155-159
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• 2021

This study aimed to develop strain-specific polymerase chain reaction (PCR) primers to detect Fusobacterium hwasookii KCOM 1249^T, F. hwasookii KCOM 1253, F. hwasookii KCOM 1256, F. hwasookii KCOM 1258, and F. hwasookii KCOM 1268 on the basis of nucleotide sequences of a gene specific to each strain. The unique genes for each F. hwasookii strain were determined on the basis of their genome sequences using Roary. The strain-specific PCR primers based on each strain-specific gene were designed using PrimerSelect. The specificity of each PCR primer was determined using the genomic DNA of the 5 F. hwasookii strains and 25 strains of oral bacterial species. The detection limit and sensitivity of each strain-specific PCR primer pair were determined using the genomic DNA of each target strain. The results showed that the strain-specific PCR primers correspond to F. hwasookii KCOM 1249^T, F. hwasookii KCOM 1253, F. hwasookii KCOM 1258, F. hwasookii KCOM 1256/F. nucleatum subsp. polymorphum KCOM 1260, or F. hwasookii KCOM 1268/Fusobacterium sp. oral taxon 203 were developed. The detection limits of these strain-specific PCR primers ranged from 0.2 to 2 ng of genomic DNA for each target strain. The results suggest that these strain-specific PCR primers are valuable in quality control for detecting specific F. hwasookii strains.

• 한국어병학회지
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• 제17권3호
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• pp.159-169
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• 2004

2003년 5월과 2003년 10월동안에 제주도내 5개소의 넙치 종묘배양장에서 초기 먹이로 공급 되어지는 동물성 플랑크톤인 rotifer와 20-30일령 넙치 자어에서 장관백탁증 원인균으로 알려진 V. ichthyoenteri를 분리하기 위해 실험한 결과 총 71개의 Vibrio sp. 분리가 되었고, 생화학적 동정결과 2개의 그룹에서 24개의 V ichthyoenteri가 동정 되었다. V. ichthyoenteri의 신속한 검출을 위한 종특이적 primer를 V. ichthyoenteri(KCCM 40870)ISR의 특이적인 서열을 이용하여 제작하였다. V. ichthyoenteri를 포함한 20종의 Vibrio속 균주의 genomic DNA와 18group 분리균주 genomic DNA를 PCR한 결과 V. ichthyoenteri 만의 특이적인 band가 생성됨을 알 수가 있다. 따라서 V. ichthyoenteri(KCCM 40870) ISR의 서열로 제작한 primer가 넙치 자치어에 발병하는 장관백탁증 원인균인 Vibrio ichthyoenteri의 신속한 검출과 정확한 동정을 할 수 있는 molecular marker로 이용할 수 있음을 확인하였다.

• 산업기술연구
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• 제28권A호
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• pp.141-147
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• 2008

Several contaminated bacteria such as Lactobacillus brevis and Pediococcus damnosus in beer production cause beer spoilage by producing off flavours and turbidity. Detection of these organisms is complicated by the strict anaerobic conditions and lengthy incubation times required for their cultivation, consequently there is a need for more rapid detection methods. Recently, two contaminated strains were isolated from vessel of beer production and identified as Lactobacillus species by API kit identificaton as well as 16S-23S ITS sequencing analyses. Two isolated strains were named as Lactobacillus sp. HLA1 and Lactobacillus HLB2, respectively. A polymerase chain reaction (PCR) method was developed for the rapid and specific detection of Lactobacillus sp.. Two sets of primer pairs (HLA1-F/HLA1-R and HLB2-F/HLB2-R) were designed for the amplification of a 1576 base pair (bp) fragment of the HLA1 16S-23S rRNA gene and 1888 bp fragement of the HLB2 16S-23S rRNA. Amplified PCR products were highly specific to detect corresponding bacteria when other contaminated strains were used as PCR templates. However, detection of both strains were limited when $100{\mu}{\ell}$ of cultured samples were mixed with $100m{\ell}$ of beer sample in arbitrary manner. The sensitivity of the assay still needs to be improved for direct detection of the small amounts of bacteria present in beer.

• The Plant Pathology Journal
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• 제29권4호
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• pp.357-363
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• 2013

The fungus Venturia nashicola is the causal agent of scab on Asian pears. For the rapid and reliable identification as well as sensitive detection of V. nashicola, a PCR-based technique was developed. DNA fingerprints of three closely related species, V. nashicola, V. pirina, and V. inaequalis, were obtained by random amplified polymorphic DNA (RAPD) analysis. Two RAPD markers specific to V. nashicola were identified by PCR, after which two pairs of sequence characterized amplified region (SCAR) primers were designed from the nucleotide sequences of the markers. The SCAR primer pairs, designated as D12F/D12R and E11F/E11R, amplified 535-bp and 525-bp DNA fragments, respectively, only from genomic DNA of V. nashicola. The specificity of the primer sets was tested on strains representing three species of Venturia and 20 fungal plant pathogens. The nested PCR primer pair specific to V. nashicola was developed based on the sequence of the species-specific 525-bp DNA fragment amplified by primer set E11F/E11R. The internal primer pair Na11F/Na11R amplified a 235-bp fragment from V. nashicola, but not from any other fungal species tested. The nested PCR assay was sensitive enough to detect the specific fragment in 50 fg of V. nashicola DNA.

• Mycobiology
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• 제37권4호
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• pp.317-319
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• 2009

In this study, in an effort to develop a method for the molecular detection of Tricholoma matsutake in Korea from other closely related Tricholomataceae, a species-specific PCR primer pair, TmF and TmR, was designed using nuclear ribosomal intertranscribed spacer (ITS) sequences. The DTmF and DTmR sequences were 5'-CCTGACGCCAATCTTTTCA-3' and 5'- GGAGAGCAGACTTGTGAGCA-3', respectively. The PCR primers reliably amplified only the ITS sequences of T. matsutake, and not those of other species used in this study.

• Mycobiology
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• 제30권4호
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• pp.197-201
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• 2002

Specific primer sets based on ribosomal DNA(rDNA) internal transcribed specer(ITS) sequences were designed for rapid detection of Phellinus linteus and P. baumii. Polymerase chain reaction(PCR) with these primers produced unique bands for each Phellinus species. The annealing temperature range is from $40^{\circ}C\;to\;55^{\circ}C$. The length of PCR products(P. linteus and P. baumii) using designed combinative primer sets of PL1F, PL2R, PB1F, PB2R, ITS5F and ITS4R, were from 520 by to 730 bp. Fifteen strains of Phellinus species including P. linteus, P. baumii, P. weirianus, P. johnsonianus, P. rhabarberinus, P. pini, P. gilvus, P. igniarius, P. nigricans and P. laevigatus were examined in this study. Five strains, including two isolated strains of P. linteus(MPNU 7001 and MPNU 7002), and two isolated strains of P. baumii(MPNU 7004 and MPNU 7005) were shown to have about 520 bp (PL1F-PL2R), 700 bp (TTS5F-PL2R) and 600 bp (PB1F-ITS4R) -sized PCR single bands respectively. This molecular genetic technique provided a useful method for rapid detection and identification of P. linteus and P. baumii.

• ALGAE
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• 제35권2호
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• pp.133-144
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• 2020

Pythium porphyrae is responsible for devastating outbreaks in seaweed farms of Pyropia, the most valuable cultivated seaweed worldwide. While the genus Pythium contains many well studied pathogens, the genome of P. porphyrae has yet to be sequenced. Here we report the first available gene repertoire of P. porphyrae and a preliminary analysis of pathogenicity-related genes. Using ab initio detection strategies, similarity based and manual annotation, we found that the P. porphyrae gene repertoire is similar to classical phytopathogenic Pythium species. This includes the absence of expanded RxLR effector family and the detection of classical pathogenicity-related genes like crinklers, glycoside hydrolases, cellulose-binding elicitor lectin-like proteins and elicitins. We additionally compared this dataset to the proteomes of 8 selected Pythium species. While 34% of the predicted proteome appeared specific to P. porphyrae, we could not attribute specific enzymes to the degradation of red algal biomass. Conversely, we detected several cellulases and a cutinase conserved with plant-pathogenic Pythium species. Together with the recent report of P. porphyrae triggering disease symptoms on several plant species in lab-controlled conditions, our findings add weight to the hypothesis that P. porphyrae is a reformed plant pathogen.

• Journal of Microbiology
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• 제43권spc1호
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• pp.65-84
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• 2005

Invasive candidiasis is associated with high morbidity and mortality. Clinical diagnosis is complicated by a lack of specific clinical signs and symptoms of disease. Laboratory diagnosis is also complex because circulating antibodies to Candida species may occur in normal individuals as the result of commensal colonization of mucosal surfaces thereby reducing the usefulness of antibody detection for the diagnosis of this disease. In addition, Candida species antigens are often rapidly cleared from the circulation so that antigen detection tests often lack the desired level of sensitivity. Microbiological confirmation is difficult because blood cultures can be negative in up to 50% of autopsy-proven cases of deep-seated candidiasis or may only become positive late in the infection. Positive cultures from urine or mucosal surfaces do not necessarily indicate invasive disease although can occur during systemic infection. Furthermore, differences in the virulence and in the susceptibility of the various Candida species to antifungal drugs make identification to the species level important for clinical management. Newer molecular biological tests have generated interest but are not yet standardized or readily available in most clinical laboratory settings nor have they been validated in large clinical trials. Laboratory surveillance of at-risk patients could result in earlier initiation of antifungal therapy if sensitive and specific diagnostic tests, which are also cost effective, become available. This review will compare diagnostic tests currently in use as well as those under development by describing their assets and limitations for the diagnosis of invasive candidiasis.

• 한국해양학회지:바다
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• 제15권1호
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• pp.36-40
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• 2010

선박평형 수는 유독 와편모조류 및 다양한 미세조류의 국제적인 이동경로로 알려져 있다. 본 연구에서는 선박평형 수에 있는 와편모조류의 다양성을 조사하기 위하여 와편모조류 특이적인 PCR primer와 종 특이적인 real-time PCR 유전자 탐침자를 이용하였다. 선박평형 수 시료에 대한 광학현미경 조사에서는 와편모조류가 매우 낮은 농도로 관찰되었지만, SSU rDNA의 cloning 및 염기서열 분석 결과에서는 기생 와편모조류, 초미세플랑크톤, 어패류 폐사 원인종 등 다양한 종류가 확인되었다. 본 연구 결과는 종 톡이적 PCR primer와 같은 분자생물학적 방법이 선박 평형 수에 외래 유입종의 신속 정확한 진단에 유용함을 보여주고 있다.

• 한국균학회소식:학술대회논문집
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• 한국균학회 2015년도 추계학술대회 및 정기총회
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• pp.41-41
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• 2015

Oomycetes belong to the kingdom Straminipila, a remarkably diverse group which includes brown algae and planktonic diatoms, although they have previously been classified under the kingdom Fungi. These organisms have evolved both saprophytic and pathogenic lifestyles, and more than 60% of the known species are pathogens on plants, the majority of which are classified into the order Peronosporales (includes downy mildews, Phytophthora, and Pythium). Recent phylogenetic investigations based on DNA sequences have revealed that the diversity of oomycetes has been largely underestimated. Although morphology is the most valuable criterion for their identification and diversity, morphological species identification is time-consuming and in some groups very difficult, especially for non-taxonomists. DNA barcoding is a fast and reliable tool for identification of species, enabling us to unravel the diversity and distribution of oomycetes. Accurate species determination of plant pathogens is a prerequisite for their control and quarantine, and further for assessing their potential threat to crops. The mitochondrial cox2 gene has been widely used for identification, taxonomy and phylogeny of various oomycete groups. However, recently the cox1 gene was proposed as a DNA barcode marker instead, together with ITS rDNA. To determine which out of cox1 or cox2 is best suited as universal oomycete barcode, we compared these two genes in terms of (1) PCR efficiency for 31 representative genera, as well as for historic herbarium specimens, and (2) in terms of sequence polymorphism, intra- and interspecific divergence. The primer sets for cox2 successfully amplified all oomycete genera tested, while cox1 failed to amplify three genera. In addition, cox2 exhibited higher PCR efficiency for historic herbarium specimens, providing easier access to barcoding type material. In addition, cox2 yielded higher species identification success, with higher interspecific and lower intraspecific divergences than cox1. Therefore, cox2 is suggested as a partner DNA barcode along with ITS rDNA instead of cox1. Including the two barcoding markers, ITS rDNA and cox2 mtDNA, the multi-locus phylogenetic analyses were performed to resolve two complex clades, Bremia lactucae (lettuce downy mildew) and Peronospora effuse (spinach downy mildew) at the species level and to infer evolutionary relationships within them. The approaches discriminated all currently accepted species and revealed several previously unrecognized lineages, which are specific to a host genus or species. The sequence polymorphisms were useful to develop a real-time quantitative PCR (qPCR) assay for detection of airborne inoculum of B. lactucae and P. effusa. Specificity tests revealed that the qPCR assay is specific for detection of each species. This assay is sensitive, enabling detection of very low levels of inoculum that may be present in the field. Early detection of the pathogen, coupled with knowledge of other factors that favor downy mildew outbreaks, may enable disease forecasting for judicious timing of fungicide applications.