• Journal of Applied Biological Chemistry
• /
• v.57 no.2
• /
• pp.137-140
• /
• 2014

A gene encoding thermostable pectinase (TmPec) was isolated from hyperthermophilic microorganism, Thermotoga maritima. The open reading frame (ORF) of TmPec gene is 1,104 bp long and encodes 367 amino acid residues with a molecular weight of 40,605 Da. To analyze the enzymatic activity and biochemical properties, the ORF of TmPec gene excluding putative signal sequence of 27 amino acids was introduced into the E. coli expression vector, pRSET-B, and overexpressed in E. coli BL21. Protein concentration of purified recombinant TmPec was 1.1 mg/mL with specific activity of 56 U/mg protein on pectin. The recombinant TmPec showed the highest activity at around $85-95^{\circ}C$, and at around pH 6.5. It was stable at temperature below $85^{\circ}C$. In the presence of $Ca^{2+}$, the activity of recombinant TmPec was increased to 146.3% of normal level. In contrast, $Ba^{2+}$ and Mn2+ showed strong inhibition to the recombinant TmPec.

• Proceedings of the Korean Society of Sericultural Science Conference
• /
• 2002.10a
• /
• pp.60-60
• /
• 2002

No Abstract, See Full Text

• Proceedings of the Korean Society of Fisheries Technology Conference
• /
• 2001.05a
• /
• pp.146-147
• /
• 2001

Lectins or carbohydrate-binding proteins are proteins of non-immune origin, which is able to agglutinate cells, and precipitate polysaccharides and glycoconjugates (Goldstein et al., 1980). Lectins with diverse physiological roles are widely distributed to the various plant, microorganisms, invertebrates and vertebrates. The ubiquitous occurrence of lectins in nature and their ability to recognize complementary sugars provided a stimulus for the continuous research for their biochemical properties and physiological functions (Raz and Lotan, 1987). (omitted)

• Proceedings of the Korean Society of Fisheries Technology Conference
• /
• 2001.05a
• /
• pp.232-233
• /
• 2001

The isozymic polymorphism among the Oncorhynchus masou subspecies (O. m. masou and O. m. ishikawai) and the genetic variation in the O. mykiss species (rainbow trout and its albino mutant) were examined in present study. The biochemical marker might be identified at the sublevel of species. The aims of this study is to examine such feasibility of using the isozyme polymorphisms of the fish management and characterization between subspecies or morphomutants such as albinism. (omitted)

• Archives of Pharmacal Research
• /
• v.16 no.2
• /
• pp.140-146
• /
• 1993

A colostral protein that augments natural killer (NK) cell activity was isolated from bovine colostrum. This protein, designated matemal immunity enhancing factor (MIEF), increased NK cell-mediated cytotxicity against human tumor targets wheb added to cultures of resting peripheral blood lymphocytes. The NK cell stimulatory activity of the MIEF was demonstrated at the concentrations as low as 0.1-0.01 $\mu$g/ml. Purified MIEF showed an apparent molecular weight of 22,000 in SDS-polyacrylamide gel electrophoresis. The unusual biochemical characteristics of the MIEF distinguish it from other cytokines. The MIEF was soluble at a cold tgemperature, and precipitated by raising the temperature. This themal precipitability was reversible, and dependent on the concentration, pH and ionic strength. Maximal precipitation was observed at neutral pH, and higher ionic strength.

• Korean Journal of Veterinary Service
• /
• v.44 no.4
• /
• pp.321-326
• /
• 2021

The study characterized Trueperella pyogenes (T. pyogenes) from caseous lymphadenitis (CLA) in Korean native goats (KNG). CLA samples (n=191) were obtained from abattoir-slaughtered KNG. Pus were obtained and Corynebacterium pseudotuberculosis was detected by PCR using PLD gene. Three PLD-negative samples (1.57%) from supramammary lymph node were subjected to bacterial culture. Isolates were identified using 16S rRNA and biochemically characterized by APIZYM. Phylogenetic and biochemical analyses identified the isolates as T. pyogenes, and have shown separate clusters and varied enzyme reaction, suggesting genotypic and phenotypic diversity. This first report of T. pyogenes-induced CLA in KNG provided information for further investigations.

• Journal of Species Research
• /
• v.10 no.4
• /
• pp.344-349
• /
• 2021

The purpose of this study was to isolate and identify wild yeasts from soil of Gyeongju city, and Haemadipsa rjukjuana of Gageodo Island, characterizing unrecorded yeast strains from Korea. The molecular analysis of the D1/D2 domain of 26S rDNA of yeast was performed using the Basic Local Alignment Search Tool (BLAST). No official report exists describing these three species: one species in the genus Candida, one species in the genus Debaryomyces, and one species in the genus Solicoccozyma. Candida saitoana YL9, Debaryomyces fabryi YL1, and Solicoccozyma terrea 20g9-1 are recorded for the first time from Korea. All three strains were oval shaped and polar binding, while positive for glucose, ᴅ-xylose, and ᴅ-cellobiose. Morphological, physiological, and biochemical properties are described in the species descriptions.

• Journal of Species Research
• /
• v.13 no.1
• /
• pp.100-104
• /
• 2024

The purpose of this study was to isolate and identify wild yeasts from soil samples collected in Daegu and Cheongju city, Republic of Korea. To identify the wild yeast strains, pairwise sequence comparisons of D1/D2 region of the 26S rRNA gene sequence were done using Basic Local Alignment Search Tool (BLAST). The cell morphologies were observed by phase contrast microscope and assimilation test are done using API 20C AUX kit. All strains were assigned to the phylum Basidiomycota. Among 13 strains, 11 strains were previously reported, but two strains were unreported from the Republic of Korea. The two unrecorded yeast strains, GW1-3 and PG1-1-10C, belong to the genus Solicoccozyma (family Piskurozymaceae, order Filobasidiales, class Tremellomycetes). The two strains had oval-shaped and polar budding cells. This research showed the morphological and biochemical properties of the two unreported yeast species that had not officially reported in Korea.

• Journal of Species Research
• /
• v.13 no.1
• /
• pp.105-110
• /
• 2024

The purpose of this study was to isolate and identify wild yeasts from soil samples collected in Seoul and Daejeon, Republic of Korea. To identify wild yeast strains, pairwise sequence comparisons of D1/D2 region of the 26S rRNA gene sequence were done using Basic Local Alignment Search Tool (BLAST). The cell morphologies were observed by phase contrast microscope and carbon source assimilation test were done using API 20C AUX kit. Among the 13 isolated strains, 11 strains were previously reported, but two strains have never been reported from Republic of Korea. The 13 strains were assigned to the phylum Basidiomycota. The two unrecorded yeast strains B2UV-201 and DJ1-5-B-10C belong to the genera Rhodotorula and Rhodosporidiobolus, respectively. The two unrecorded yeast strains are oval shaped and polar budding cells. This research focuses on the morphological and biochemical properties of the two unreported yeast species that have not officially been reported in Korea.

• Food Science and Biotechnology
• /
• v.14 no.4
• /
• pp.503-508
• /
• 2005

Screening for antilisterial activity was performed in about three thousand isolates of lactic acid bacteria (LAB) from Chinese cabbage kimchi, and finally based on the relatively stronger antilisterial activities eight bacterial strains were selected. The bacteria were further characterized in terms of their tolerance to artificial gastric juice, pH 2.5, bile salts (0.3% oxgall), and to the different NaCl concentrations. Of the isolates, YK005 was especially investigated for its physiological characteristics due to its inhibitory activity against gram-positive Listeria monocytogenes as well as gram-negative Escherichia coli O157:H7, as they have been constantly reported to be resistant against bacteriocins produced by a number of LAB strains. YK005 was found to be rod-shaped, $3.8\;{\mu}m$ long ${\times}\;0.5\;{\mu}m$ wide, non-sporeforming, non-motile, catalase-negative, and produced gas from glucose (heterolactic). Based on the biochemical data obtained by API 50 CHL medium, the isolate was tentatively identified as Lactobacillus brevis. To validate the result obtained by the biochemical identification, rRNA-based PCR experiments using a pair of species-specific primers for L. brevis were conducted and a single band of 1400 bp was observed, which strongly indicated that YK005 belongs to L. brevis. The LAB isolates are potentially exploited as human probiotic organisms and are employed to control some food-borne pathogens like L. monocytogenes.