• Korean Journal of Food Science and Technology
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• v.48 no.2
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• pp.165-171
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• 2016

Physicochemical properties of waxy maize flours prepared by hydrothermal and enzymatic treatments were evaluated. Waxy maize flours were hydrothermally treated using heat-moisture treatment (HMT) and annealing (ANN) and enzymatically treated using commercial enzymes (cellulase, proteinase, and pectinase). The HMT-modified waxy maize flours had low water absorption index (WAI), melting enthalpy, viscosity, and crystallinity. However, ANN-modified and enzymatically modified waxy maize flours had high WAI, melting enthalpy, and viscosity. X-ray diffraction analysis of ANN-modified and enzymatically modified waxy maize flours revealed a typical A-type pattern and displayed sharper crystalline peaks than those observed for the control groups (native waxy maize flours). In contrast, the crystallinity of HMT-modified waxy maize flours were decreased by hydrothermal treatment.

• Microbiology and Biotechnology Letters
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• v.26 no.6
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• pp.523-528
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• 1998

We isolated microorganism secreting antimicrobial substance from tomato and identified as Enterococcus faecium. This substance was completely inactivated by pretense treatment and retained activity after catalase treatment. This result indicated that the antimicrobial activity of this substance was due to proteinaceous substance known as bacteriocin. The bacteriocin inhibited growth of Gram positive bacteria, such as Listeria monocytogenes, Leuconostoc mesenteroides, Lactobacillus plantarum, Streptococcus agalactiae, Streptococcus pyrogenes, and Gram negative bacteria, such as Pseudomonas aeruginosa. Purification of the bacteriocin was achieved by ethanol precipitation, ion exchange chromatography on CM Sepharose CL-6B, and gel filtration on Sephacryl S-100 HR. After these purification steps, the specific activity of the bacteriocin was increased 35.8 fold compared with culture broth. Purified bacteriocin was shown single band on SDS-PAGE and molecular weight was estimated 51 kDa. The residual activity of this bacteriocin was 3.3% at 10$0^{\circ}C$ for 60 min, and this bacteriocin was stable at pH 2~7.

• Korean Journal of Veterinary Research
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• v.43 no.3
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• pp.383-392
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• 2003

Insulin-like growth factors (IGFs) and their binding proteins (IGFBPs) are important regulators on the development of maternal tissues during pregnancy. This study was performed to examine the relationship between maternal IGFs/IGFBPs system (i.e: IGF-I, II, their receptors, and IGFBPs) in pre- and post-partum rats. The liver and kidney are important organs for the synthesis of IGFs and IGFBPs in adults. The levels of materanal IGFs and IGFBPs in serum, liver, and kidney were examined at 14 and 21 days of gestation and at 3, 7, 11, and 14 days after birth. The expression of IGFs and their receptors mRNA was also examined in fetal and maternal rat liver, kidney. IGF-I concentrations in maternal serum and liver were decreased during pregnancy. However, IGF-I concentration in maternal kidney was increased, having maximal effect at 14 days of gestation. IGF-I concentrations were decreased in serum, liver, and kidney of postpartum rat, compared to control (p < 0.05). On the other hand, IGF-II concentrations in serum, liver, and kidney were increased during pregnancy (p<0.05) and gradually decreased to control level in postpartum period. The levels of IGFBP-3 and IGFBP-2 are expressed in serum, liver, and kidney. However, IGFBP-3 is mainly expressed in serum and liver, and IGFBP-2 in kidney. The levels of IGFBP-3 and IGFBP-2 in maternal serum were markedly decreased during pregnancy and gradually recovered to control level during postpartum period by western ligand blotting. However, there was no change of IGFBP-3 and IGFBP-2 levels by western immunoblotting. The levels of IGFBP-3 and IGFBP-2 in maternal liver and kidney also showed the same pattern of serum, although the main IGFBP is different. In normal rat serum, IGF-I 150 kDa and 50 kDa carrier proteins were detected. The level of IGF-I 150 kDa carrier proteins in pregnant rat was decreased compared to normal rat, but that of 50 kDa carrier proteins was increased. IGFBP-3 protease activity was identified in pregnant rat serum and maternal placenta, and it was inhibited by EDTA ($Ca^{2+}$ chelating agent) and aprotinin (serine proteinase inhibitor). Taken together, these results suggest that the changes of IGFs and IGFBPs in maternal rats are regulated by liver and kidney IGFs and their receptors mRNA during the pregnancy.

• Journal of Plant Biotechnology
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• v.47 no.2
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• pp.157-163
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• 2020

Calmodulin (CaM) mediates cellular Ca²⁺ signals in the defense responses of plants. We previously reported that GmCaM-4 and 5 are involved in salicylic acid-independent activation of disease resistance responses in soybean (Glycine max). Here, we generated a GmCaM-4 cDNA construct under the control of the cauliflower mosaic virus (CaMV) 35S promoter and transformed this construct into potato (Solanum tuberosum L.). The constitutive over-expression of GmCaM-4 in potato induced high-level expression of pathogenesis-related (PR) genes, such as PR-2, PR-3, PR-5, phenylalanine ammonia-lyase (PAL), and proteinase inhibitorII (pinII). In addition, the transgenic potato plants exhibited enhanced resistance against a bacterial pathogen, Erwinia carotovora ssp. Carotovora (ECC), that causes soft rot disease and showed spontaneous lesion phenotypes on their leaves. These results strongly suggest that a CaM protein in soybean, GmCaM-4, plays an important role in the response of potato plants to pathogen defense signaling.

• Microbiology and Biotechnology Letters
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• v.14 no.2
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• pp.145-153
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• 1986

For the inactivation of venoms, the chemical methods are generally applied. In the chemical method many works have been carried out with the chemical reagents and immunological antiserums. However, all inhibitory effect of these chemicals acting on snake venomes may well be due not to the specific, but to the nonspecific inhibitory action. Therefore, it is necessary to separate venom into its compositional active proteins and develop specific inhibitor which acts on the each protein. Until now, there have not been any reports about the substance which acts on snake venom as a specific inhibitor. Recently in 1979, we had actually isolated a specific venom inhibitor(ISV) which has a strong inhibitory activity against the proteinase of snake venom of Colubridae. In our experiments described here, a strain of Aspergillus sp., isolated from soil, was able to produce a biological active substance. The partial crystallized substance had a strong inhibitory activity against hemorrhagic action of snake venom of Colubridae. For the inhibitory action of the sample on the lethality of venom, the substance prevented completely the lethal action of the hemorrhagic factor when they were treated with enough amount of the substance. The edema factor of whole venom of Agristrodon bromohoffi brevicaudus was completely inhibited, but those of HR-I and HR-II of Trimeresurus flavoviridis venom were inhibited about 50%, when they were treated with the substance of half amount of venom. On the other hand, from the result of subcutaneous hemorrhage in a rabbit, it was concluded that two kinds of antihemorrhagic substance might be produced by the strain used in this work.

• Journal of Animal Science and Technology
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• v.45 no.4
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• pp.659-666
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• 2003

Endoglucanase A from Clostridium thermocellum which is resistant to pancreatic proteinase was selected out of numbers cellulases then were expressed in lactobacilli. Recombinant lactobacilli expression vector, pSD1, harboring the endoglucanase gene from C. thermocellum under the control of its own promoter, was constructed. Both L. bulgaricus and L. plantarum were electrotransformed with pSD1. The endoglucanase activities of 0.120 and 0.144 U/ml were found in culture media of L. bulgaricus and L. plantarum containing pSD1, respectively. In vitro survival characteristics of the transformed lactobacilli were tested. Both L. bulgaricus and L. plantarum showed a similar resistance to low pH 3. Moreover, L. plantarum was bile-salt resistant in the presence of 0.3 and 1% oxgall. L. bulgaricus and L. plantarum showed a rather homogenous resistant pattern against the tested antibiotics. Both of the strains were resistant to amikacin, gentamicin, streptomycin, kanamycin, and colistin.

• Microbiology and Biotechnology Letters
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• v.29 no.2
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• pp.90-95
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• 2001

Kinetic Analysis of Cathepsin B Inhibitor Using a Spectrophotometric Assay. Han, Kil-Hwan and SangDal Kim*. Department of Applied MicrobioJ0f5Yt Yeungnam UniversitYt Kyongsan 77 2-749, Korea - The KHS 10, C4Hl10~6 formula produced from Streptomyces luteogriseus KT-] 0 effectively inhibited a lysosomal cysteine proteinase, cathepsin B. It inhibited the enzyme activity of cathepsin B competitively when the N a-CBZ-Llysine p-nitrophenyl ester HC] (CLN) was used as a substrate. The inhibition const:mt (Ki) of KHS 1 0 for cathepsin B detennined by spectrophotometeric assay was 430 nM. The effective inhibition of cathepsin B was observed at $25^{\circ}C$ :md pH 6.0. The cathepsin B inhibitor, KHSlO needed a preincubation of cathepsin B with the inhibitor for over 5 min. The KHS 10 preserved over 80% inhibition activity even after heat-treatment at $100^{\circ}C$ for ] hr.

• Microbiology and Biotechnology Letters
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• v.44 no.1
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• pp.9-18
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• 2016

Two Bacillus strains, CJW15 and SSD8, with strong antibacterial activities were isolated from cheonggukjang. Both were identified as B. amyloliquefaciens strains after gene sequencing of rRNA and recA. CJW15 strongly inhibited the growth of B. cereus (ATCC14579), Listeria monocytogenes (ATCC19111), and Lactococcus lactis (ATCC11454). In comparison, SSD8 inhibited the growth of B. cereus (ATCC14579) and Enterococcus faecium (ATCC19953). The antibacterial activities of the two strains were not affected when exposed to a temperature of $100^{\circ}C$ for 15 min and were quite stable in acidic (pH 3) and alkaline (pH 12) pH conditions. Enzymatic treatments (trypsin, pepsin, proteinase K, and protease) had no effect on the activity of CJW15, but reduced the activity of SSD8 by half. Both isolates possess genes involved in the synthesis of lipopeptides (e.g. surfactin, fengycin, iturin, and iturin A), and genes encoding subtilin, a bacteriocin. Moreover, both isolates have fibrinolytic activities as well.

• Microbiology and Biotechnology Letters
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• v.35 no.4
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• pp.325-333
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• 2007

One bacterium with high proteinase production and spore-forming ability was isolated from korean traditional soybean paste(doenjang). The isolated strain was identified as Bacillus subtilis, based on gram-staining, biochemical properties and l6S rRNA gene sequencing, and designated as B. subtilis DJI. Its growth rate was very fast, and it reached its stationary phase within 9 h, and then started to form spores. Bacterial-koji and doenjang were prepared using B. subtilis DJI. Chemical components of the doenjang were determined after 2 months of aging period: amino nitrogen 507 mg%, crude protein 14.3%, crude fat 4.8% and water 54.9%. The composition of total and free amino acids and their ratios of doenjang were changed during the aging period. Among total amino acids in DJI doenjang, glutamic acid, aspartic acid, leucine and arginine were the major amino acids. The fibrinolytic activities of DJI doenjang and traditional doenjangs were 909.7 units/ml and $363.3{\sim}618.6\;units/ml$, respectively. Flavor compounds of DJI doenjang and traditional doenjang were extracted by SDE(simultaneous steam distillation and extraction), and analyzed by GC/MS; DJI doenjang possessed the typically favorable flavor compounds in traditional korean doenjang, with reduced off-flavor compounds.

• Journal of Microbiology and Biotechnology
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• v.22 no.11
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• pp.1532-1539
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• 2012

The ${\alpha}$-galactosidase-coding gene agaAJB13 was cloned from Sphingomonas sp. JB13 showing 16S rDNA (1,343 bp) identities of ${\leq}97.2%$ with other identified Sphingomonas strains. agaAJB13 (2,217 bp; 64.9% GC content) encodes a 738-residue polypeptide (AgaAJB13) with a calculated mass of 82.3 kDa. AgaAJB13 showed the highest identity of 61.4% with the putative glycosyl hydrolase family 36 ${\alpha}$-galactosidase from Granulicella mallensis MP5ACTX8 (EFI56085). AgaAJB13 also showed <37% identities with reported protease-resistant or Sphingomonas ${\alpha}$-galactosidases. A sequence analysis revealed different catalytic motifs between reported Sphingomonas ${\alpha}$-galactosidases (KXD and RXXXD) and AgaAJB13 (KWD and SDXXDXXXR). Recombinant AgaAJB13 (rAgaAJB13) was expressed in Escherichia coli BL21 (DE3). The purified rAgaAJB13 was characterized using p-nitrophenyl-${\alpha}$-D-galactopyranoside as the substrate and showed an apparent optimum at pH 5.0 and $60^{\circ}C$ and strong resistance to trypsin and proteinase K digestion. Compared with reported proteaseresistant ${\alpha}$-galactosidases showing thermolability at $50^{\circ}C$ or $60^{\circ}C$ and specific activities of <71 U/mg with or without protease treatments, rAgaAJB13 exhibited a better thermal stability (half-life of >60 min at $60^{\circ}C$) and higher specific activities (225.0-256.5 U/mg). These sequence and enzymatic properties suggest AgaAJB13 is the first identified and characterized Sphingomonas ${\alpha}$-galactosidase, and shows novel protease resistance with a potential value for basic research and industrial applications.