• Korean Journal of Fisheries and Aquatic Sciences
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• v.45 no.5
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• pp.507-512
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• 2012

One leptocephalus (TL 59.9 mm) from the family Ophichthidae collected from Jeju Island, Korea, was identified using morphological and molecular methods. Our ophichthid leptocephalus was identified as belonging to the genus Muraenichthys based on morphological characters: 157 myomeres; the origin of the dorsal fin located a little in front of the anus; a distinct melanophore present on the opercle; and six gut swellings present. An analysis of 886 base pairs of the 12S rRNA mtDNA sequences showed that our leptocephalus must be Muraenichthys gymnopterus, because its sequences were concordant with those of an adult M. gymnopterus (d=0.001) and next to those of Muraenichthys sp. leptocephalus (d=0.034). Here, we are the first to describe the morphological characteristics of the M. gymnopterus leptocephalus.

• The Korean Journal of Mycology
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• v.37 no.1
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• pp.86-90
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• 2009

The C. militaris belongs to entomopathogenic fungi, which have their specific sequences in internal transcribed spacer regions (ITS1 and ITS2) depending on species. In this study, to identify the phylogenetic relationship of the strain hybrided by mating of C. militaris, we compared DNA sequences of ITS regions and 5.8S ribosomal DNA (rDNA) repeat unit of hybrid strain and its parental strains. The result revealed that hybrid strains are C. militaris species. In addition, cordycepins produced by hybrid strains and other strains of C. militaris were analyzed by HPLC with 20mM $KH_2PO_4$ of mobile phase and C-18 columns. The result indicated that the strain hybrided by mating produce higher concentration of phytochemical cordycepin than other C. militaris strains.

• Parasites, Hosts and Diseases
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• v.55 no.1
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• pp.39-45
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• 2017

The present study was performed to reveal the morphological characteristics and molecular phylogenetic position of Platynosomum fastosum Kossack, 1910. A total 167 specimens of P. fastosum were collected in 8 (4.9%) out of 163 sets of gall-bladders and bile ducts of cats. The number of worms was 1-105 per infected cat. This species was characterized by having a long and slender body, slightly larger ventral sucker than the oral sucker, indistinct prepharynx, small pharynx, short esophagus, bifurcation midway between 2 suckers, and ceca extending to the posterior end of the body. The length of the partial sequences of ITS1 and 5.8S rDNA of P. fastosum were 990 bp, GC-rich. AT/GC ratio was 0.9, there were 9 polymorphic sites, and intraspecific variations ranged from 0.1% to 0.9%. Phylogenetic analyses by neighbor-joining phylogram inferred from ITS1 rDNA sequences revealed that the genetic distance between P. fastosum specimens ranged from 0.3 to 1.5% while the smallest interspecific distance among dicrocoeliid species was 20.9 %. The redescription and genetic characters of P. fastosum are taxonomically important to recognize future different species of the genus Platynosomum showing high intraspecific and morphological variability.

• Animal Systematics, Evolution and Diversity
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• v.27 no.1
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• pp.47-52
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• 2011

Creeping ctenophores, Coeloplana species, were collected by SCUBA divers throughout the year (November 2006 to June 2010) from the branches and polyp masses of encrusting dendronephthyas at a depth of 20-32m off Munseom Island (Seogwipo-si, Jeju-do, Korea). A single individual of a newly recorded species in Korea, Coeloplana bocki Komai, 1920, was collected together with C. anthostella from the same location on 16 August 2009. A large number of individuals of each species were subsequently collected from the host Dendronephthya aff. dendritica on 20 June 2010. C. bocki can be distinguished from C. anthostella Song and Hwang, 2010 and C. komaii Utinomi, 1963 by its unique blue and orange colored stripes, and/or the branching and anastomosing milky-white stripes encircling the aboral sense organ towards the margin. The detailed morphology and molecular sequence information (nuclear 18S rDNA, internal transcribed spacer 1, and mitochondrial cox1 gene sequences) for C. bocki is provided, and C. bocki and C. anthostella are compared.

• Microbiology and Biotechnology Letters
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• v.24 no.3
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• pp.371-375
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• 1996

TFD is a transcription factor database which consists of short functional DNA sequences called as signals and their references. SIGNAL SCAN, developed by Dan S. Prestridge, is used to determine what signals of TFD may exist in a DNA sequence. This program searches TFD database by using a simple algorithm for character string comparison. We developed TFSCAN that aims at searching for signals in an input DNA sequence more efficently than SIGNAL SCAN. Our algorithms consist of two parts, one constructs an automata by scanning sequences of rFD, the other searches for signals through this automata. Searching for signal-related references is radically improved in time by using an indexing method. Usage of TFSCAN is very simple and its output is obvious. We developed and installed a TFSCAN input form and a CGI program in GINet Web server, to use TFSCAN. The algorithm applying automata showed drastical results in improvement of computing time. This approach may apply to recognizing several biological patterns. We have been developing our algorithm to optimize the automata and to search more sensitively for signals.

• Korean journal of applied entomology
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• v.53 no.3
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• pp.247-260
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• 2014

To identify the species of Trichogramma occurring in the corn fields of Korea as egg parasitoids of Ostrinia furnacalis, we sequenced the full-length of ITS2 nuclear rDNA from 112 parasitoids collected during this study. As a reference to distinguish species, we also retrieved full-length ITS2 sequences of 60 Trichogramma species from the NCBI GenBank database. On the basis of the size and 3'terminal sequence pattern of the ITS2 sequences, the Trichogramma samples collected in this study were divided into three groups (K-1, -2, and -3). Evolutionary distances (d) within and between groups based on ITS2 sequences were estimated to be ${\leq}0.005$ and ${\geq}0.080$, respectively. In the net average distance between groups or species, the d value between K-1 and T. ostriniae, K-2 and T. dendrolimi, and K-3 and T. confusum was the lowest, with values of 0.016, 0.001, and 0.002, respectively. In the phylogenetic tree, K-1 and K-2 were clustered with T. ostriniae and T. dendrolimi, respectively. However, K-3 was clustered with three different species, namely, T. confusum, T. chilonis, and T. bilingensis. NCBI BLAST results revealed that parasitoids belonging to K-1 and K-2 showed 99% identity with T. ostriniae and T. dendrolimi, respectively. Parasitoids in K-3 collected from Hongcheon showed 99-100% identity with T. confusum and T. chilonis, and one parasitoid in K-3 collected from Gochang had 98% identity with T. bilingensis, T. confusum, and T. chilonis. On the basis of these results, we infer that the species of Trichogramma collected in this study are closely related to T. ostriniae (K-1) and T. dendrolimi (K-2). However, it was not possible to distinguish species of K-3 using the ITS2 sequence alone.

• The Korean Journal of Mycology
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• v.38 no.2
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• pp.105-111
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• 2010

Lentinus lepideus, known as train wrecker fungus, has been used for nutritional and medicinal purposes. Recently, commercial cultivation technique and a new cultivar of the mushroom were developed. To investigate the genetic diversity and phylogenetic relationship for identifying the mushroom strains and cultivar, one commercial and 13 strains of Lentinus lepideus from different geographical regions of Korea were analyzed by ITS regions of rDNA and RAPD of genomic DNA. Three strains of Lentinus edodes were also used for the analysis. The size of the ITS1 and ITS2 regions of rDNA from the different strains varied from 173 to 179 bp and 203 to 205 bp, respectively. The sequence of ITS1 was more variable than that of ITS2, while the 5.8S sequences were identical with 156 base pairs. A phylogenetic tree based on the ITS region sequences indicated that selected strains could be classified into four clusters, while 3 strains of L. edodes was divided into a new cluster. Ten primers out of 20 arbitrary primers used in the RAPD-PCR efficiently amplified the genomic DNA. The numbers of amplified DNA bands varied with the primers and strains, with polymorphic DNA fragments in the range from 0.2 to 2.6 kb. The results showed that phylogenetic relationship among Korean strains of Lentnus lepideus is high, but genetic diversity is low.

• The Korean Journal of Mycology
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• v.40 no.4
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• pp.266-270
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• 2012

Stem canker and tuber rot symptoms were observed on yam grown in Andong and Jinju, Korea in 2011. A total of 20 isolates of Rhizoctonia and allied fungi were obtained from the symptomatic plants. Among the isolates, 8 isolates were identified as Rhizoctonia solani and 12 isolates as Ceratobasidium sp. based on rDNA-internal transcribed spacer (ITS) sequence similarity. In the cluster analysis of rDNA-ITS sequences, 7 isolates of R. solani belonged to AG 2-2IIIB and remaining one to AG 1-1A. In addition, among the 12 isolates of Ceratobasidium sp., 7 isolates belonged to AG-Fa, three isolates to AG-A and the other two isolates to AG-Fb and AG-O, respectively. Pathogenicity tests showed that all the R. solani AG 2-2IIIB isolates are pathogenic on stem and tuber of yam but R. solani AG 1-1A and all the Ceratobasidium isolates are non-pathogenic. The results indicate that R. solani AG 2-2IIIB is an important pathogen causing stem canker and tuber rot on yams grown in the study areas. This is the first report of R. solani AG 2-2IIIB causing stem canker and tuber rot of yam in Korea.

• The Korean Journal of Mycology
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• v.36 no.1
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• pp.63-65
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• 2008

Four strains of Piptoporus betulinus were isolated from a trunk of the Betula ermani in Seorak mountain. These strains were studied to observe whether they are originated from the same genet or not, by using the method of pairing culture between strains and by comparing part of the nuclear rDNA of ITS regions amplified with NSI1 and ITS4B primers. The demarcation line was not formed on the potato dextrose agar plates in the combinations of two different strains. Partial nuclear rDNA sequences of the four strains were also the same. As a result, it is considered in high probability that they are derived from a single spawn.

• Mycobiology
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• v.40 no.4
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• pp.255-257
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• 2012

Among 80 types of yeast isolated from wild flowers in Daejeon, Korea, two species that have not yet been identified by phylogenetic analysis of the internal transcribed spacer-2 (ITS2) genes and 26S rDNA sequences were identified as Candida sp. 44-C-1 and Cryptococcus sp. 9-D-1. Neither of the newly identified species formed ascospores, while Candida sp. 44-C-1 formed pseudomycelium and Cryptococcus sp. 9-D-1 did not.