• Bulletin of the Korean Chemical Society
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• v.34 no.9
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• pp.2680-2684
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• 2013

Protein kinases (PKs) are an important source of drug targets, especially in oncology. With 500 or more kinases in the human genome and only few kinase inhibitors approved, kinase inhibitor discovery is becoming more and more valuable. Because the discovery of kinase inhibitors with an increased selectivity is an important therapeutic concept, many researchers have been trying to address this issue with various methodologies. Although many attempts to predict the activity and selectivity of kinase inhibitors have been made, the issue of selectivity has not yet been resolved. Here, we studied kinase selectivity by generating predictive models and analyzing their descriptors by using kinase-profiling data. The 5-fold cross-validation accuracies for the 51 models were between 72.4% and 93.7% and the ROC values for all the 51 models were over 0.7. The phylogenetic tree based on the descriptor distance is quite different from that generated on the basis of sequence alignment.

• ALGAE
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• v.34 no.4
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• pp.267-275
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• 2019

Three new species of the genus Micractinium were collected from five localities on the South Shetland Islands in maritime Antarctica, and their morphological and molecular characteristics were investigated. The vegetative cells are spherical to ellipsoidal and a single chloroplast is parietal with a pyrenoid. Because of their simple morphology, no conspicuous morphological characters of new species were recognized under light microscopy. However, molecular phylogenetic relationships were inferred from the concatenated small subunit rDNA, and internal transcribed spacer (ITS) sequence data indicated that the Antarctic microalgal strains are strongly allied to the well-supported genus Micractinium, including M. pusillum, the type species of the genus, and three other species in the genus. The secondary structure of ITS2 and compensatory base changes were used to identify and describe six Antarctic Micractinium strains. Based on their morphological and molecular characteristics, we characterized three new species of Micractinium: M. simplicissimum sp. nov., M. singularis sp. nov., and M. variabile sp. nov.

• Journal of Marine Bioscience and Biotechnology
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• v.2 no.1
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• pp.60-67
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• 2007

For the first time in Vietnam, morphological and molecular studies of a species belonging to Bacillariophyceae collected in Northern coast of Vietnam are presented. Observations with microscope showed that this species belong to genus: Pseudo-nitzschia and seem like P. pungens. Sequence data from the partial 18S small subunit ribosomal RNA gene (18S rDNA) and the internal transcribed spacer 1 - 5.8S - internal transcribed 2 have been used to determine clearly and generate a phylogenetic framework of the obtained sequences to previously reported sequences in GenBank. These results allowed us to highlight described species of Bacillariophyceae in Northern coast of Vietnam. Furthermore, accumulation of molecular study would be helpful for the identification of scientific name of harmful algal species and further taxonomic studies in Vietnam.

• Korean Journal of Plant Taxonomy
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• v.52 no.3
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• pp.127-143
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• 2022

This study was conducted to clarify the phylogenetic position and relationships of Korean Poaceae taxa. A total of 438 taxa including 155 accessions of Korean Poaceae (representing 92% and 72% of Korean Poaceous genera and species, respectively) were employed for phylogeny reconstruction. Sequence data of eight chloroplast DNA markers were used for molecular phylogenetic analyses. The resulted phylogeny was mostly concordant with previous phylogenetic hypotheses, especially in terms of subfamilial and tribal relationships. Several taxa-specific indels were detected in the molecular phylogeny, including a 45 bp deletion in rps3 (PACMAD [Panicoideae, Arundinoideae, Chloridoideae, Micrairoideae, Aristidoideae, Danthonioideae] clade), a 15 bp deletion in ndhF (Oryzeae + Phyllorachideae), a 6 bp deletion in trnLF (Poeae s.l.), and two (17 bp and 378 bp) deletions in atpF-H (Pooideae). The Korean Poaceae members were classified into 23 tribes, representing eight subfamilies. The subfamilial and tribal classifications of the Korean taxa were generally congruent with a recently published system, whereas some subtribes and genera were found to be non-monophyletic. The taxa included in the PACMAD clade (especially Andropogoneae) showed very weak and uncertain phylogenetic relationships, presumably to be due to evolutionary radiation and polyploidization. The reconstructed phylogeny can be utilized to update the taxonomic positions of the newly examined grass accessions.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.56 no.5
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• pp.708-715
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• 2023

Hybridization is a major production method used to combine beneficial traits from two different species to obtain a potentially dominant trait. In China, Takifugu obscurus and T. rubripes were artificially crossed, and the resulting hybrids had an average body weight 38.06-8.93% higher than that of the parental species, which enabled the hybrids to be grown in freshwater. This study aimed to provide the basic data necessary for the classification of T. obscurus♀×T. rubripes♂ hybrids in terms of economic value and market potential. Morphological comparing the morphology of hybrids and parental species, we discovered that the hybrids had intermediate traits of the parental species. In morphometrics, the hybrid index (HI) value of head length against standard length was close to the trait of T. rubripes, and the HI values of preanal length and predorsal length were close to those of T. obscurus; however, the HI values of nasal length, snout length, length of anal fin, length of pectoral fin, caudal peduncle depth and caudal peduncle length were found to be unique characteristics of the hybrids. Regarding molecular analysis, a 99.8% nucleotide sequence similarity was found between the hybrid and T. obscurus.

• The KIPS Transactions:PartD
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• v.10D no.6
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• pp.897-906
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• 2003

The traditional animal phylogenetic tree is to align the body structure of the animal phylums from simple to complex based on the initial development character. Currently, molecular systematics research based on the molecular, it is on the fly, is again estimating prior trend and show the new genealogy and interest of the evolution. In this paper, we generate the training set which is obtained from a DNA sequence ans apply to the classification. We made use of the mitochondrial DNA for the experiment, and then proved the accuracy using the MEGA program which is anaysis program, it is used in the biology field. Although the result of the mining has to proved through biological experiment, it can provede the methodology for the efficient classify and can reduce the time and effort to the experiment.

• Mycobiology
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• v.32 no.1
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• pp.24-34
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• 2004

Molecular approaches, internal transcribed spacer(ITS) sequences of ribosomal DNA, and Universal Rice Primer Polymerase Chain Reaction(URP-PCR) were used to investigate the genetic diversity, taxonomic complexity, and relationships of Trichoderma species in mushroom farms. Forty-one isolates of 13 Trichoderma spp. were used in this study and clustered into eight groups. The DNA fingerprint patterns and ITS1 region sequence alignment data showed similar results, but not in some species, such as T. virens, T. atroviride, T. harzianum, and T. aureoviride. Results of this study have proven that the morphology-based taxonomic system has some limitations in terms of classification. The data obtained in this study would be a good index for classifying indistinguishable Trichoderma strains.

• Journal of Microbiology
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• v.44 no.4
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• pp.432-438
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• 2006

Twelve actinomycete strains were isolated from Egyptian soil. The isolated actinomycete strains were then screened with regard to their potential to generate antibiotics. The most potent of the producer strains was selected and identified. The cultural and physiological characteristics of the strain identified. the strain as a member of the genus Streptomyces. The nucleotide sequence of the 16S rRNA gene (1.5kb) of the most potent strain evidenced a 99% similarity with Streptomyces spp. and S. aureofaciens 16S rRNA genes, and the isolated strain was ultimately identified as Streptomyces sp. MAR01. The extraction of the fermentation broth of this strain resulted in the isolation of one major compound, which was active in vitro against gram-positive, gram-negative representatives and Candida albicans. The chemical structure of this bioactive compound was elucidated based on the spectroscopic data obtained from the application of MS, IR, UV, $^1H$ NMR, $^{13}C$ NMR, and elemental analysis techniques. Via comparison to the reference data in the relevant literature and in the database search, this antibiotic, which had a molecular formula of $C_{19}H_{29}NO_2$ and a molecular weight of 303.44, was determined to differ from those produced by this genus as well as the available known antibiotics. Therefore, this antibiotic was designated Meroparamycin.

• BMB Reports
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• v.40 no.3
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• pp.315-324
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• 2007

The novel $\alpha$-amylase purified from locally isolated strain, Bacillus sp. KR-8104, (KRA) (Enzyme Microb Technol; 2005; 36: 666-671) is active in a wide range of pH. The enzyme maximum activity is at pH 4.0 and it retains 90% of activity at pH 3.5. The irreversible thermoinactivation patterns of KRA and the enzyme activity are not changed in the presence and absence of $Ca^{2+}$ and EDTA. Therefore, KRA acts as a $Ca^{2+}$-independent enzyme. Based on circular dichroism (CD) data from thermal unfolding of the enzyme recorded at 222 nm, addition of $Ca^{2+}$ and EDTA similar to its irreversible thermoinactivation, does not influence the thermal denaturation of the enzyme and its Tm. The amino acid sequence of KRA was obtained from the nucleotide sequencing of PCR products of encoding gene. The deduced amino acid sequence of the enzyme revealed a very high sequence homology to Bacillus amyloliquefaciens (BAA) (85% identity, 90% similarity) and Bacillus licheniformis $\alpha$-amylases (BLA) (81% identity, 88% similarity). To elucidate and understand these characteristics of the $\alpha$-amylase, a model of 3D structure of KRA was constructed using the crystal structure of the mutant of BLA as the platform and refined with a molecular dynamics (MD) simulation program. Interestingly enough, there is only one amino acid substitution for KRA in comparison with BLA and BAA in the region involved in the calcium-binding sites. On the other hand, there are many amino acid differences between BLA and KRA at the interface of A and B domains and around the metal triad and active site area. These alterations could have a role in stabilizing the native structure of the loop in the active site cleft and maintenance and stabilization of the putative metal triad-binding site. The amino acid differences at the active site cleft and around the catalytic residues might affect their pKa values and consequently shift its pH profile. In addition, the intrinsic fluorescence intensity of the enzyme at 350 nm does not show considerable change at pH 3.5-7.0.

• Journal of the korean society of oceanography
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• v.39 no.3
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• pp.172-185
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• 2004

LSU rDNA D1-D2 and SSU rDNA genes of 23 strains in seven Alexandrium (Halim) species, A. tamarense (Lebour) Balech, A. catenella (Whedon et Kofoid), A. fraterculus (Balech) Balech, A. affine (Inoue et Fukuyo) Balech, A. insuetum Balech, A. pseudogonyaulax (Biecheler) Horiguchi ex Yuki et Fukuyo and A. tamiyavanichii Balech, were sequenced and the data were used for molecular phylogenetic analysis. The sequence data revealed 11 and 7 ribotypes in the LSU rDNA D1-D2 region and 4 and 17 ribotypes in the SSU rDNA region of A. catenella and A. tamarense, respectively. Other Alexandrium species had also 1 to 5 ribotypes in the two regions. With the exception of CMC2 and CMC3 of A. catenella, all A. tamarense and A. catenella strains had a common ribotype, a functionally expressed rRNA gene (here termed type A), in both gene regions. In addition to the functionally expressed gene, several pseudogenes were obtained that were found to be good tools to analyze the population designation of regional isolates by grouping them according to shared ribotypes. From the phylogenetic analysis of the sequence data determined in this study and retrieved from GenBank, the genus Alexandrium was divided into 14 groups: 1) A. tamarense, 2) A. excavatum, 3) A. catenella, 4) Tasmanian A. tamarense, 5) A. affine (and/or A. concavum), 6) Thai A. tamarense, 7) A. tamiyavanichii, 8) A. fraterculus, 9) A. margalefii, 10) A. andersonii, 11) A. ostenfeldii, 12) A. minutum (or A. lusitanicum), 13) A. insuetum, and 14) A. pseudogonyaulax. The SSU rDNA gene sequence of A. fundyense was so similar to those of A. tamarense used in this study that the two species were difficult to discriminate each other. A. tamiyavanichii was closest to the A. tamarense strain isolated in Thailand and close to the long chain-forming species of A. affine and A. fraterculus. The phylogenetic tree showed that A. margalefii, A. andersonii, A. ostenfeldii, A. minutum and A. insuetum constituted the basal relative complex, and that A. pseudogonyaulax is an ancestral taxon in the genus Alexandrium.