• 한국약용작물학회:학술대회논문집
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• 2008.05a
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• pp.298-299
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• 2008

• Proceedings of the Korean Society of Life Science Conference
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• 2007.10a
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• pp.122.2-122.2
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• 2007

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• The Plant Pathology Journal
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• v.33 no.1
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• pp.21-33
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• 2017

Citrus blast caused by bacterium Pseudomonas syringae is a very important disease of citrus occuring in many areas of the world, but with few data about genetic structure of the pathogen involved. Considering the above fact, this study reports genetic characterization of 43 P. syringae isolates obtained from plant tissue displaying citrus blast symptoms on mandarin (Citrus reticulata) in Montenegro, using multilocus sequence analysis of gyrB, rpoD, and gap1 gene sequences. Gene sequences from a collection of 54 reference pathotype strains of P. syringae from the Plant Associated and Environmental Microbes Database (PAMDB) was used to establish a genetic relationship with our isolates obtained from mandarin. Phylogenetic analyses of gyrB, rpoD, and gap1 gene sequences showed that P. syringae pv. syringae causes citrus blast in mandarin in Montenegro, and belongs to genomospecies 1. Genetic homogeneity of isolates suggested that the Montenegrian population might be clonal which indicates a possible common source of infection. These findings may assist in further epidemiological studies of this pathogen and for determining mandarin breeding strategies for P. syringae control.

• The Plant Pathology Journal
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• v.33 no.5
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• pp.514-521
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• 2017

Spinach is a vegetable crop which is widely grown over a large area especially in Punjab province of Pakistan. Leaf curling and enations on spinach plant collected shown to be associated with the begomovirus Pedilanthus leaf curl virus (PeLCV) and Shahdadpur strain of Cotton leaf curl Multan betasatellite ($CLCuMB^{Sha}$). Defective molecules of half and quarter size derived from monopartite begomoviruses are usually generated by the deletion of virion-sense sequences. Characterization of defective molecules of PeLCV from spinach revealed that the molecules of half the size are derived from the deletion of complementary-sense genes while quarter size molecule appears to have evolved by further deletion. This is the first report of the begomovirus-betasatellite complex on spinach and unusual defective molecules derived from deletion of complementary-sense genes in Pakistan.

• Journal of Microbiology and Biotechnology
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• v.16 no.5
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• pp.757-763
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• 2006

Angiotensin I-converting enzyme (ACE) inhibitors have generally been very useful to remedy or prevent hypertension. This study describes the extraction and characterization of an ACE inhibitor from the fruiting body of Pholiota adiposa ASI 24012, which can be used as an antihypertensive drug. The maximal ACE inhibitory activity $(IC_{50};0.25mg)$ was obtained when the fruiting body of Pholiota adiposa ASI 24012 was extracted with distilled water at $30^{\circ}C$ for 12 h. After the purification of ACE inhibitor with ultrafiltration, Sephadex G-25 column chromatography, and reverse-phase HPLC, an active fraction with an $IC_{50}$ of 0.044 mg was obtained. The purified ACE inhibitory peptide was a novel pentapeptide, showing very little similarity to other ACE inhibitory peptide sequences. The molecular mass of the purified ACE inhibitor was estimated to be 414 daltons with a sequence of Gly-Glu-Gly-Gly-Pro, and showed a clear antihypertensive effect on spontaneously hypertensive rats (SHR) at a dosage of 1 mg/kg.

• BMB Reports
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• v.35 no.3
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• pp.255-261
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• 2002

GTP cyclohydrolase I (E.C. 3.5.4.16) is a homodecameric protein that catalyzes the conversion of GTP to 7,8-dihydroneopterin triphosphate (H2NTP), the initial step in the biosynthesis of pteridines. It was proposed that the enzyme complex could be composed of a dimer of two pentamers, or a pentamer of tightly associated dimers; then the active site of the enzyme was located at the interface of three monomers (Nar et al. 1995a, b). Using mutant enzymes that were made by site-directed mutagenesis, we showed that a decamer of GTP cyclohydrolase I should be composed of a pentamer of five dimers, and that the active site is located between dimers, as analyzed by a series of size exclusion chromatography and the reconstitution experiment. We also show that the residues Lys 136, Arg139, and Glu152 are of particular importance for the oligomerization of the enzyme complex from five dimers to a decamer.

• BMB Reports
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• v.39 no.1
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• pp.105-110
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• 2006

We have screened 766 strains of fungi from the BIOTEC Culture Collection (BCC) for xylanases working in extreme pH and/or high temperature conditions, the so-called extreme xylanases. From a total number of 32 strains producing extreme xylanases, the strain BCC7928, identified by using the internal transcribed spacer (ITS) sequence of rRNA to be a Marasmius sp., was chosen for further characterization because of its high xylanolytic activity at temperature as high as $90^{\circ}C$. The crude enzyme possessed high thermostability and pH stability. Purification of this xylanase was carried out using an anion exchanger followed by hydrophobic interaction chromatography, yielding the enzyme with >90% homogeneity. The molecular mass of the enzyme was approximately 40 kDa. The purified enzyme retained broad working pH range of 4-8 and optimal temperature of $90^{\circ}C$. When using xylan from birchwood as substrate, it exhibits $K_m$ and $V_{max}$ values of $2.6{\pm}0.6\;mg/ml$ and $428{\pm}26\;U/mg$, respectively. The enzyme rapidly hydrolysed xylans from birchwood, beechwood, and exhibited lower activity on xylan from wheatbran, or celluloses from carboxymethylcellulose and Avicel. The purified enzyme was highly stable at temperature ranges from 50 to $70^{\circ}C$. It retained 84% of its maximal activity after incubation in standard buffer containing 1% xylan substrate at $70^{\circ}C$ for 3 h. This thermostable xylanase should therefore be useful for several industrial applications, such as agricultural, food and biofuel.

• Journal of Forest and Environmental Science
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• v.31 no.3
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• pp.214-224
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• 2015

The economy of India and so also of many Asian countries depends on bamboos and their uses are not only in domestic items but also in rural housing and raw materials to several industries and germplasm characterization is an important link between the conservation and utilization of plant genetic resources. Classical taxonomic studies of the bamboos are based on floral morphology and growth habit, which can cause problems in identification due to erratic flowering coupled with different biotic agencies and environmental factors. Identification and genetic relationships among accessions of Thamnocalamus falconeri were investigated using morphology and random amplified polymorphic DNAs (RAPD) technique. Analysis started by using 51 vegetative characters and forty two 10-mer primers that allowed us to distinguish different genotypes hailing from different eco- zones of Garhwal Himalayas (India). The selected primers (12) were used for identification and for establishing a profiling system to estimate genetic diversity. A total of 79.33% polymorphism was estimated by using 12 selected primers. The genetic similar analysis was conducted based on binary digits i.e. presence (1) or absence (0) of bands, which revealed a wide range of variability among the species whereas genetic relatedness was quite high based on vegetative characters. Cluster analysis clearly showed two major clusters for both of the markers viz. morphology and RAPD belonging to 10 accessions of T. falconeri. Two major clusters were further divided into minor clusters. Cluster based on RAPD marker showed grouping of accessions of closed locality whereas analogy was reported for vegetative traits. The RAPD technique has the potential for use in species identification and genetic relationships studies of bamboo for breeding program.

• BMB Reports
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• v.38 no.5
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• pp.624-631
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• 2005

Tuberculosis, caused by Mycobacterium tuberculosis, continues to be one of the main diseases to mankind. It is urgent to discover novel drug targets for appropriate antimicrobial agents against this human pathogen. The shikimate pathway is onsidered as an attractive target for the discovery of novel antibiotics for its essentiality in bacteria and absence in mammalian cells. The Mycobacterium tuberculosis aroE-encoded shikimate dehydrogenase was cloned, expressed and purified. Sequence alignment analysis shows that shikimate dehydrogenase of Mycobacterium tuberculosis exhibit the pattern of G-X-(N/S)-V-(T/S)-X-PX-K, which is highly conserved within the shikimate dehydrogenase family. The recombinant shikimate dehydrogenase spectrum determined by CD spectroscopy showed that the percentages for $\alpha$-helix, $\beta$-sheet, $\beta$-turn, and random coil were 29.2%, 9.3%, 32.7%, and 28.8%, respectively. The enzymatic characterization demonstrates that it appears to be fully active at pH from 9.0 to 12, and temperature $63^{\circ}C$. The apparent Michaelis constant for shikimic acid and $NADP^+$ were calculated to be about $29.5\;{\mu}M$ and $63\;{\mu}M$. The recombinant shikimate dehydrogenase catalyzes the substrate in the presence of $NADP^+$ with an enzyme turnover number of $399\;s^{-1}$. Zymological studies suggest that the cloned shikimate dehydrogenase from M. tuberculosis has a pretty activity, and the work should help in the discovery of enzyme inhibitors and further of possible antimicrobial agents against Mycobacterium tuberculosis.

• Proceedings of the Korean Society of Crop Science Conference
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• 2005.04a
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• pp.234-235
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• 2005