• 농업과학연구
• /
• 제42권2호
• /
• pp.99-103
• /
• 2015

Potato virus T (PVT) is a plant pathogen in the family Betaflexiviridae, group IV single-stranded positive sense RNA viruses. The major host of PVT is potato, and it has been reported in Ullucus tuberosus, Oxalis tuberosa and Tropaeolum tuberosum. This study aimed at developing reverse transcription (RT)-polymerase chain reaction (PCR) and nested PCR techniques for specific detection of PVT. Finally, Two RT-PCR primer sets were developed and verified. The RT-PCR products were amplified to 734 (PVT RT-PCR primer set 6) and 828 bp (PVT RT-PCR primer set 29) long to detect PVT. The nested PCR primer sets [PVT-N70/C20 ($734{\rightarrow}315bp$) and PVT-N75/C30 ($828{\rightarrow}529bp$)] were developed which are high sensitivity and verification for detection of PVT. Furthermore, a modified-positive control plasmid is use to verify contamination of laboratory in PVT detection. This study supported the diagnose PVT in potato or PVT related hosts.

• BMB Reports
• /
• 제52권12호
• /
• pp.700-705
• /
• 2019

The bacterial effector protein RavZ is secreted by the intracellular pathogen Legionella pneumophila and inhibits host autophagy through an irreversible deconjugation of mammalian ATG8 (mATG8) proteins from autophagosome membranes. However, the roles of the LC3 interacting region (LIR) motifs in RavZ function remain unclear. In this study, we show that a membrane-targeting (MT) domain or the LIR motifs of RavZ play major or minor roles in RavZ function. A RavZ mutant that does not bind to mATG8 delipidated all forms of mATG8-phosphatidylethanolamine (PE) as efficiently as did wild-type RavZ. However, a RavZ mutant with a deletion of the MT domain selectively delipidated mATG8-PE less efficiently than did wild-type RavZ. Taken together, our results suggest that the effects of LIR motifs and the MT domain on RavZ activity are complementary and work through independent pathways.

• Journal of Periodontal and Implant Science
• /
• 제39권1호
• /
• pp.37-44
• /
• 2009

Purpose: Tetracycline and its chemically modified non-antibacterial analogues can inhibit certain host-derived tissue destructive collagenases such as matrix metalloproteinases. The purpose of this study was to evaluate clinical and microbiologic effects of the subantimicrobial dose of doxycycline(SDD) in conjunction with scaling and root planing. Materials and methods: A total of 30 patients with chronic periodontitis who were going to receive scaling and root planing were randomly allocated to receive either a doxycycline hyclate for 3 months or nothing. Clinical probing depth, clinical attachment level, gingival recession, and bleeding on probing were measured by one periodontist. After a periodontal examination, microbial samples were collected using sterile paper points. The effect of SDD in conjunction with scaling and root planing on alterations of the periodontal pathogens (Aggregatibacter actinomycetemcomitans, Tannerella forsythia, Porphyromonas gingivalis) were also assessed using l6S rRNA polymerase chain reaction. Results: During the treatment period, clinical parameters for both treatment group and control group were improved. After 3 months, reductions in probing depth and gains in clinical attachment level were significantly greater for the SDD group than control group. Microbial analysis showed that there was no alteration of the periodontal pathogens and no difference between the groups. Conclusion: This study suggested that the subantimicrobial dose of doxycycline as an adjunct therapy with scaling and root planing might be effective and safe in the management of chronic periodontitis.

• 한국양식학회지
• /
• 제21권1호
• /
• pp.13-18
• /
• 2008

Marine birnavirus(MABV)는 중요한 어류 병원체로서 일본 양식산 방어서 처음 분리되어 이후 다양한 해산어종에서 MABV 분리가 보고되었으며 환경적인 샘플인 저질, 해양의 동물성 플랑크톤과 해수에서도 MABV 유전자가 검출되고 있다. 본 연구는 Marine birnavirus disease 에 대한 예방학적 접근의 일환으로서 자연산 어류로부터의 MABV 검출 및 지리적 분포, 보균 어종에 대한 유전학적인 조사를 목적으로 2003년과 2005년도에 동중국해역 3지점, 서해안 5지점 그리고 남해안 5지점에서 어류를 채집하였다. RT-PCR(Reverse transcriptase-Polymerase Chain Reaction)을 이용한 연구결과 자연산 해산어류 160마리 중 13종 17마리에서 MABV가 거출되어 감염율10.6%를 보였다. 조사된 13종의 어류 중 특히 농어목에서 가장 높는 검출율을 보였다. 자연산 어류에서 분리한 MABV 분리균주는 염기서열 분석에서 94.7%-100%, 아미노산 분석에서 97.2-100% 유사성을 나타내었으며 IPNV strain과는 구분되며 MABV에 속하였다.

• 한국균학회지
• /
• 제34권2호
• /
• pp.122-124
• /
• 2006

2005년 3월경 경남농업기술원 움막저장고에서 저장중이던 초석잠의 덩이줄기에 이상증상이 발생하였다. 병징은 초석잠 덩이줄기 부분이 수침상으로 물러지고 썩으면서 병반부위에 회색의 곰팡이가 많이 생겼다. 분생포자는 무색, 단포자이며 난형 또는 타원형으로 크기는 $5{\sim}16{\times}4{\sim}12{\mu}m$였다. 분생포자경은 갈색으로 격막이 있고 나무가지 모양이며, 폭은 $14{\sim}30{\mu}m$였다. 균사생육과 균핵형성 적온은 $20^{\circ}C$였다. 초석잠에서 병징과 병원균의 균학적 특징, 병원성을 조사한 결과 Botrytis cinerea Persoon:Fries에 의한 초석잠 잿빛곰팡이병으로 동정하였다.

• Mycobiology
• /
• 제48권4호
• /
• pp.313-320
• /
• 2020

In Pleurotus sp., green mold, which is considered a major epidemic, is caused by several Trichoderma species. To develop a rapid molecular marker specific for Trichoderma spp. that potentially cause green mold, eleven Trichoderma species were collected from mushroom farms and the Korean Agricultural Culture Collection (KACC). A dominant fungal isolate from a green mold-infected substrate was identified as Trichoderma pleuroticola based on the sequences of its internal transcribed spacer (ITS) and translation elongation factor 1-α (tef1) genes. In artificial inoculation tests, all Trichoderma spp., including T. atroviride, T. cf. virens, T. citrinoviride, T. harzianum, T. koningii, T. longibrachiatum, T. pleurotum, and T. pleuroticola, showed pathogenicity to some extent, and the observed symptoms were soaked mycelia with a red-brown pigment and retarded mycelium regeneration. A molecular marker was developed for the rapid detection of wide range of Trichoderma spp. based on the DNA sequence alignment of the ITS1 and ITS2 regions of Trichoderma spp. The developed primer set detected only Trichoderma spp., and no cross reactivity with edible mushrooms was observed. The detection limits for the PCR assay of T. harzianum (KACC40558), T. pleurotum (KACC44537), and T. pleuroticola (CAF-TP3) were found to be 500, 50, and 5 fg, respectively, and the detection limit for the pathogen-to-host ratio was approximately 1:10,000 (wt/wt).

• 한국균학회지
• /
• 제33권1호
• /
• pp.35-37
• /
• 2005

2002년부터 2003년까지 2년 동안 경남 거제시 학동면 조팝나무 재배농가에서 잎과 줄기에 이상증상이 심하게 발생하였다. 병징은 처음 잎에 암적갈색의 작은 둥근 반점이 많이 생기고, 줄기에 검은색 반점이 나타나며 진전됨에 따라 약간 움푹하게 들어가고 긴 타원형으로 검게 썩는다. 심하게 발생하면 병든 가지 윗부분은 말라 죽는다. 균총은 PDA배지에서 회색이고 분생포자 모양은 단세포, 원통형이며 크기는 $6{\sim}12{\times}3{\sim}5\;{\mu}m$였다. 강모의 색깔은 암갈색이고 바늘모양의 원추형이며 크기는 $23{\sim}42{\times}2{\sim}4\;{\mu}m$이었다. 균사생육 최적온도는 $30^{\circ}C$였다. 분리된 병원균으로 병원성을 검정한 결과, 자연 감염된 병징과 똑같았다. 이상의 결과를 가지고 본 병해를 Colletotrichum gloeosporioides에 의한 조팝나무 탄저병으로 명명할 것을 제안한다.

• Journal of Microbiology and Biotechnology
• /
• 제25권8호
• /
• pp.1246-1256
• /
• 2015

Chlamydophila psittaci is an important intracellular pathogen. Persistent infection is an important state of the host-parasite interaction in this chlamydial infection, which plays a significant role in spreading the organism within animal populations and in causing chronic chlamydiosis and serious sequelae. In this study, a C. psittaci persistent infection cell model was induced by penicillin G, and real-time quantitative PCR was used to study the transcriptional levels of 10 C. psittaci genes (dnaA, dnaK, ftsW, ftsY, grpE, rpsD, incC, omcB, CPSIT_0846, and CPSIT_0042) in acute and penicillin-G-induced persistent infection cultures. Compared with the acute cultures, the penicillin-G-treated cultures showed a reduced chlamydial inclusion size and a significantly decreased number of elementary body particles. Additionally, some enlarged aberrant reticulate body particles were present in the penicillin-G-treated cultures but not the acute ones. The expression levels of genes encoding products for cell division (FtsW, FtsY) and outer membrane protein E encoding gene (CPSIT_0042) were downregulated (p < 0.05) from 6 h post-infection onward in the persistent infection cultures. Also from 6 h post-infection, the expression levels of DnaA, DnaK, IncC, RpsD, GrpE, and CPSIT_0846 were upregulated (p < 0.05); however, the expression level of OmcB in the persistent infection was< almost the same as that in the acute infection (p > 0.05). These results provide new insight regarding molecular activities that accompany persistence of C. psittaci, which may play important roles in the pathogenesis of C. psittaci infection.

• Journal of Microbiology and Biotechnology
• /
• 제21권7호
• /
• pp.679-685
• /
• 2011

Xanthomonas oryzae pv. oryzae (Xoo) produces a putative effector, XoAvrBs2. We expressed XoAvrBs2 homologously in Xoo with a TAP-tag at the C-terminus to enable quantitative analysis of protein expression and secretion. Addition of rice leaf extracts from both Xoo-sensitive and Xoo-resistant rice cultivars to the Xoo cells induced expression of the XoAvrBs2 gene at the transcriptional and translational levels, and also stimulated a remarkable amount of XoAvrBs2 secretion into the medium. In a T3SS-defective Xoo mutant strain, secretion of the TAPtagged XoAvrBs2 was blocked. Thus, we elucidated the transcriptional and translational expressions of the XoAvrBs2 gene in Xoo was induced in vitro by the interaction with rice and the induced secretion of XoAvrBs2 was T3SSdependent. It is the first report to measure the homologous expression and secretion of XoAvrBs2 in vitro by rice leaf extract. Our system for the quantitative analysis of effector protein expression and secretion could be generally used for the study of host-pathogen interactions.

• The Plant Pathology Journal
• /
• 제31권4호
• /
• pp.363-370
• /
• 2015

Using the Chinese cabbage (Brassica campestris) cultivar 'Chun-goang' as a host and turnip mosaic virus (TuMV) as a pathogen, we studied the effects of ambient temperature ($13^{\circ}C$, $18^{\circ}C$, $23^{\circ}C$, $28^{\circ}C$ and $33^{\circ}C$) on disease intensity and the speed of systemic infection. The optimal temperature for symptom expression of TuMV was $18-28^{\circ}C$. However, symptoms of viral infection were initiated at $23-28^{\circ}C$ and 6 days post infection (dpi). Plants maintained at $33^{\circ}C$ were systemically infected as early as 6 dpi and remained symptomless until 12 or 22 dpi, depending on growth stage at the time of inoculation. It took 45 days for infection of plants grown at $13^{\circ}C$. Quantitative realtime polymerase chain reaction (q-PCR) results showed that the accumulation of virus coat protein was greater in plants grown at $23-28^{\circ}C$. The speed of systemic infection increased linearly with rising ambient temperature, up to $23^{\circ}C$. The zero-infection temperature was $10.1^{\circ}C$. To study the effects of abruptly elevated temperatures on systemic infection, plants inoculated with TuMV were maintained at $10^{\circ}C$ for 20 d; transferred to a growth chamber at temperatures of $13^{\circ}C$, $18^{\circ}C$, $23^{\circ}C$, $28^{\circ}C$, or $33^{\circ}C$ for 1, 2, or 3 d; and then moved back to $10^{\circ}C$. The numbers of plants infected increased as duration of exposure to higher temperatures and dpi increased.