• Advances in materials Research
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• v.7 no.3
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• pp.185-194
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• 2018

The mechanism of biological materials structure is very complex and has optimal properties compared to engineering materials. Top Neck mollusks shells, as an example of biological materials, have hierarchical structure, which 95 percent of its structure is Aragonite and 5 percent organic materials. This article detected mechanical properties of the Top Neck mollusks shell as a Nano composite using Nano-indentation method in different situations. Research findings indicate that mechanical properties of the Top Neck mollusks shell including elastic modulus and hardness are higher than a fresh one preserved in -50 centigrade and also a Top Neck mollusks shell preserved in environmental conditions. Nano-indentation test results are so close in range, overall, that hardness degree is 3900 to 5200 MPa and elastic modulus is 70 to 85 GPa.

• Animal Systematics, Evolution and Diversity
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• v.23 no.2
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• pp.117-126
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• 2007

Two new species of the genus Doridicola are described as associates of opisthobranch mollusks from Korean intertidal waters: Doridicola virguatus n. sp. associated with the notaspidean Pleurobranchaea japonica Thiele and D. portincola n. sp. associated with the nudibranch Hoplodoris armata (Baba). This is the first record for the copepod associates of opisthobranch mollusks from Korea.

• The Korean Journal of Malacology
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• v.22 no.2
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• pp.109-113
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• 2006

Subcellular localization of a protein containing nuclear localization signals (NLS) has been well studied in many organisms ranging from invertebrates to vertebrates. However, no systematic analysis of NLS-containing proteins available from Mollusks has been reported. Here, we describe in silico screening of NLS-containing proteins using the mollusks database that contains 22,138 amino acids. To screen putative proteins with NLS-motif, we used both predict NLS and perl script. As a result, we have found 266 proteins containing NLS sequences which are about 1.2% out of the entire proteins. On the basis of KOG (The eukaryotic orthologous groups) analysis, we can't predict the precise functions of the NLS-containing proteins. However, we found out that these proteins belong to several types of proteins such as chromatin structure and dynamics, translation, ribosomal structure, biogenesis, and signal transduction mechanism. In addition, we have analysed these sequences based on the classes of mollusks. We could not find many from the species that are the main subjects of phylogenetic studies. In contrast, we noticed that cephalopods has the highest number of NLS-containing proteins. Thus, we have constructed mollusks NLS database and added these information and data to the mollusks database by constructing web interface. Taken together, these information will be very useful for those who are or will be studying NLS-containing proteins from mollusks.

• The Korean Journal of Food & Health Convergence
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• v.4 no.3
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• pp.22-31
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• 2018

In this present work, the amounts of toxic elements were determined in the soft tissues of mollusks (Mytilus galloprovincialis and Rapana venosa) collected from Igneada shores of the Black Sea where suggested as Marine Protection Area (MPA). M. galloprovincialis accumulated the highest amounts of Cd in winter, while the highest amounts of Cd and Hg were detected in R. venosa in winter and autumn. The concentrations of toxic elements found in the soft tissues of mollusks varied for Cd: 0.07-0.14, Hg: 0.03-0.44 and Pb: 0.09-0.21 mg/g dry wt. The estimated levels of all non-essential metals in the present work were lower than the limits permitted by European Community Regulation (EU) and the Turkish Food Codex (TFC). The estimated weekly intakes (EWI) and daily intakes (EDI) of all the through consumption of these seafood by Turkish people in the Igneada coasts of the Black Sea were quite below the permissible tolerable weekly/daily intakes for 70 kg person (PTWI / PTDI) set by FAO/WHO. As results, it can be concluded that no hazard effects on people health would be raised at present from the consumption of these mollusks' species.

• The Korean Journal of Malacology
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• v.30 no.3
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• pp.281-293
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• 2014

The biogeography and diversity patterns of the marine bivalve molluscan fauna of the East Sea coast of South Korea are analyzed. The total species richness of the continental Korean bivalve fauna, excluding insular regions (Dok-do and Ullung-do), is 304, and from north to south the species richness of bivalves increases showing a clear gradient: Gangwon, 143 species ${\rightarrow}$ Gyeongbuk, 131 ${\rightarrow}$ Gyeongnam, 183. A zonal-geographical analysis of the entire fauna shows that the great majority are warm-water mollusks, constituting 77% (subtropical, 37%, tropical-subtropical, 30%, subtropical-boreal, 10%), The number of boreal (low-boreal, widely distributed boreal and circumboreal) species is lower, 19%, whereas boreal-arctic mollusks have only 4%. This demonstrates that the bivalve molluscan fauna of the eastern coast of Korea is subtropical, and has more affinities to the fauna of the East China Sea than to the northern East Sea. Separate analysis by provinces shows the increasing role of warm-water mollusks from north to south. While tropical-subtropical and subtropical species constitute 47% (68 species) in Gangwon, their dominance increases to 71% (93 species) in Gyeongbuk, and to 80% (148 species) in Gyeongnam. The Gyeongnam bivalve fauna is the most diverse in species composition and has the largest number of "endemics" (species known only from this province), 46%. The Gangwon fauna also contains many "endemics", up to 40%, while Gyeongbuk is an intermediate zone with low "endemicity", only at one-fifth of the regional fauna, and has the most species in common among the three provinces.

• The Korean Journal of Malacology
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• v.18 no.1
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• pp.27-40
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• 2002

Beach death assemblages of bivalve mollusks were studied with respect to their species composition in six localities along the eastern coast of Korea (Gangneung, Jumunjin, Daejin, Gallam, Jukbyeon, Hupo and Chooksan). In all, thirty-nine species belonging to 30 genera and 19 families were recorded, and species diversity between the sampling sites varied from 5 to 21. Biogeographical analysis showed that studied fauna has warm-water character with the predominance of subtropical and subtropical-lowboreal species and the presence of tropical-subtropical species (in total, 77 %), and only 23 % of mollusks found are cold-water and temperate species. The most abundant species were Septifer virgatus (Wiegmann, 1837), Mytilus galloprovinciallis Lamarck, 1819, Gomphina melanaegis Romer, 1861, Ruditapes philippinarum (Adams et Reeve, 1850), Mactra chinensis Philippi, 1847 and Spisula sachalinensis (Schrenck, 1862).

• The Korean Journal of Malacology
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• v.20 no.2
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• pp.165-169
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• 2004

The BLAST server for the mollusk was constructed on the basis of the Intel Server Platform SC-5250 dual Xeon 2.8 GHz cpu and Linux operating system. After establishing the operating system, we installed NCBI (National Center for Biotechnology Information) WebBLAST package after web server configuration for cgi (common gate interface) (http://chimp.kribb.re.kr/mollusks). To build up the stand alone blast, we conducted as follows: First, we downloaded the genome information (mitochondria genome information), DNA sequences, amino acid sequences related with mollusk available at NCBI. Second, it was translated into the multifasta format that was stored as database by using the formatdb program provided by NCBI. Finally, the cgi was used for the Stand Alone Blast server. In addition, we have added the vector, Escherichia coli, and repeat sequences into the server to confirm a potential contamination. Finally, primer3 program is also installed for the users to design the primer. The stand alone BLAST gave us several advantages: (1) we can get only the data that agree with the nucleotide sequence directly related with the mollusks when we are searching BLAST; (2) it will be very convenient to confirm contamination when we made the cDNA or genomic library from mollusks; (3) Compared to the current NSBI, we can quickly get the BLAST results on the mollusks sequence information.

• The Korean Journal of Malacology
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• v.14 no.2
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• pp.161-166
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• 1998

Mollusks were collected with Ponar grab from seven stations in lower part of Han river, Korea from June 1995 through May 1996. Basket sampler with artificial substrate was also employed to collect the adhesive mollusks. In addition to above mentioned sampling stations, Bam islet was surveyed. A total of species, Corbicula fluminea, Anodonta woodiana, Unio douglasiae, Limnoperna fortunei, corbicula fenouilliana and Physa acuta, were collected in lower part of Han river. Author reviewed the literatures on the ecological survey of molluscan fauna in Han river.

• The Korean Journal of Malacology
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• v.28 no.3
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• pp.187-196
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• 2012

Recently, for the purpose of constructing artificial ecosystem, the public aquarium and experimental mesocosm systems are receiving attention. To design and establish an aquarium and mesocosm system, there is need of several materials for simulating the environment, such as sediments, rocks, and plants. Expecially for sessile mollusks, there must be proper materials to which sessile invertebrates can adhere. Nowadays, many aquariums and mesocosm systems are using dead coral skeletons for sessile mollusks. This study was proceeded to have data on the effect of dead coral skeletons on water qualities with the experiment on the environmental factors. For this purpose, I made glass tank for experiment, chose two types of dead coral skeletons imported from the Indonesia and observed the change of water qualities and decomposition efficiency of TAN (total ammonia-nitrogen), nitrite ($NO_2{^-}$) and nitrate ($NO_3{^-}$). As a result, the lager the surface area was, the more TAN, nitrite and nitrate decomposition rate increased. In addition, coral skeletons covered with crustose algae and bacteria in the tank showed faster TAN, nitrite and nitrate removal rate and stabilization. Accordingly, this experiment suggested that dead coral skeletons could be used as a sub filter for the closed system as well as an adhering plate.

• The Korean Journal of Malacology
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• v.22 no.1 s.35
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• pp.63-86
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• 2006

A list of species of bivalve mollusks, their local distributions and relative abundance in Yeongil Bay were analysed. Species richness ranging from 1 to 37 species was low (less than 10) in some stations at the entrance and in the central part of the bay. Fifteen species (Acila insignis, Nucula tenuis, Yoldia notabilis, Mytilus galloprovincialis, Arca boucardi, Axinopsida subquadrata, Felaniella usta, Mactra chinensis, Raeta pulchella, Nitidotellina hokkaidoensis, Theora fragilis, Alvenius ojianus, Callithaca adamsi, Ruditapes philippinarum and Laternula anatina) were most frequently encountered, and seven of them were most abundant numerically (per sample): Th. fragilis in the inner bay, A. insignis, N. tenuis, and A. ojianus in the outer bay, and C. adamsi, A. subquadrata, R. puichella in both parts. Local distributions of common species were described and presented in plotted data, and three distribution patterns were recognized. Biogeographical analysis shows that a majority of species (55%) belongs to the subtropical group, tropical-subtropical species (16%) play a relatively significant role, and the percentage of boreal (temperate) and boreal-arctic species is 18% which characterizes the whole fauna as subtropical. Zonal-biogeographical composition and number of species in families in Yeongil Bay are compared with those of some Japanese (Wakasa and Mutsu) and Russian (Peter the Great, Possjet and Amursky) bays of the East Sea. The absence of a number of typical warm-water embaymental mollusks in Yeongil Bay found in the north further East Sea and Japan, and the similar zonal-biogeographical structure of the inner and outer bay faunas are explained by active water exchange due to the openness of the bay, relatively low summer temperatures, and presence of upwelled cold waters.