• Applied Biological Chemistry
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• v.33 no.4
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• pp.287-292
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• 1990

Eight(I through VII) of Bowman-Birk proteinase inhibitor have been isolated from soybean with DEAE-Sephadex A-50. Inhibitor VII was a typical BBTI, showing high cysteine content(17%/mole) ud low trypsin to chymotrypsin inhibiting activity(TIA/CIA= 1.0) with the independent reactive site to each enzyme. Dissociation constant of trypsin-BBTI and chymotrypsin-BBTl complexes were $9.17{\times}10^{-9}M$ and $5.14{\times}10^{-8}M$, respectively. Inhibitor Vll was extremely heat stable. Six hours heat treatment at $100^{\circ}C$ caused only 50% decrease in it's original inhibiting activity. Except inhibitor III,6 other isoinhibitors differed from a typical BBTI in TIA/CIA, values, ranging from 3 to 29.

• Applied Biological Chemistry
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• v.42 no.4
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• pp.310-316
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• 1999

BBPI contents in domestic soybean and soybean products were investigated by the measurement of chymotrypsin inhibiting activity(C.I.A) and competitive ELISA method. In order to produce polyclonal antibody, BBPI was purified from soybean trypsin-chymotrypsin inhibitor by ion exchange chromatography and electrophoretic gel slicing. Rabbit anti-BBPI polyclonal antibody was produced with the purified BBPI as immunogen. This antibody showed relatively specific binding to BBPI and then used for the establishment of competitive ELISA method to measure BBPI contents in extracts of soybean and soybean products. The standard curve for the measurement of BBPI in soybean extracts was drawn up within the range 0.03 to $30\;{\mu}g/ml$ of BBPI. The C.I.A. and BBPI contents of 12 soybean cultivars were $8,462{\sim}12,428\;U/g$ and $482{\sim}692\;mg%$, respectively. The C.I.A. and BBPI contents were not detected in most of soybean products except soybean sprouts, which contained $10,695{\sim}13,249\;U/g$ of C.I.A. and $529{\sim}803\;mg%$ of BBPI.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.4
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• pp.1097-1104
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• 2012

Background/Aim: Pristimerin isolated from Celastrus and Maytenus spp can inhibit proteasome activity. However, whether pristimerin can modulate cancer metastasis is unknown. Methods: The impacts of pristimerin on the purified and intracellular chymotrypsin proteasomal activity, the levels of regulator of G protein signaling 4 (RGS 4) expression and breast cancer cell lamellipodia formation, and the migration and invasion were determined by enzymatic, Western blot, immunofluorescent, and transwell assays, respectively. Results: We found that pristimerin inhibited human chymotrypsin proteasomal activity in MDA-MB-231 cells in a dose-dependent manner. Pristimerin also inhibited breast cancer cell lamellipodia formation, migration, and invasion in vitro by up-regulating RGS4 expression. Thus, knockdown of RGS4 attenuated pristimerin-mediated inhibition of breast cancer cell migration and invasion. Furthermore, pristimerin inhibited growth and invasion of implanted breast tumors in mice. Conclusion: Pristmerin inhibits proteasomal activity and increases the levels of RGS4, inhibiting the migration and invasion of breast cancer cells.

• The Korean Journal of Ecology
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• v.22 no.1
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• pp.45-50
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• 1999

A bacteriocin-producing strain was isolated from kimchi at the early stage of kimchi fermentation. It was identified as Lactococcus lactis by morphological, cultural and physiological characteristics and partial sequence of 16S rDNA. The bacteriocin from isolate had antimicrobial activity against gram positive pathogenic bacteria, such as Listeria monocytogenes. Staphylococcus aureus and several strains of lactic acid bacteria but not to gram negative bacteria, Yersinia enterocolitica. The bacteriocin was sensitive to protease, protease ⅩⅣ, a-chymotrypsin and pepsin but not to lipase, trypsin and lysozyme. The bacteriocin activity was stable at pH 2-11 and temperature of 100 for 10 min. Thus, Listeria monocytogenes could be inhibited by Lactococcus lactis at early stage of fermentation.

• Bulletin of the Korean Chemical Society
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• v.35 no.12
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• pp.3571-3575
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• 2014

Proteasome, a multicatalytic protease complex, has been validated as a promising therapeutic target in oncology. Carfilzomib (Kyprolis$^{(R)}$), a tetrapeptide epoxyketone, irreversibly inhibits the chymotrypsin-like (CT-L) activity of the proteasome and has been recently approved for multiple myeloma treatment by FDA. A chemistry effort was initiated to discover the compounds that are reversibly inhibit the proteasome by replacing the epoxyketone moiety of carfilzomib with a variety of ketones as reversible and covalent warheads at the C-terminus. The newly synthesized compounds exhibited significant inhibitory activity against CT-L activity of the human 20S proteasome. When the compounds were tested for cancer cell viability, 14-8 was found to be most potent in inhibiting Molt-4 acute lymphoblastic leukemia cell line with a $GI_{50}$ of $4.4{\mu}M$. Cytotoxic effects of 14-8 were further evaluated by cell cycle analysis and Western blotting, demonstrating activation of apoptotic pathways.

• Fisheries and Aquatic Sciences
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• v.19 no.10
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• pp.42.1-42.10
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• 2016

The objectives of this study were to identify the histamine-forming bacteria and bacteriocin- producing lactic acid bacteria (LAB) isolated from Myeolchi-jeot according to sequence analysis of the 16S rRNA gene, to evaluate the inhibitory effects of the bacteriocin on the growth and histamine accumulation of histamine-forming bacteria, and to assess the physico-chemical properties of the bacteriocin. Based on 16S rRNA gene sequences, histamine-forming bacteria were identified as Bacillus licheniformis MCH01, Serratia marcescens MCH02, Staphylococcus xylosus MCH03, Aeromonas hydrophila MCH04, and Morganella morganii MCH05. The five LAB strains identified as Pediococcus acidilactici MCL11, Leuconostoc mesenteroides MCL12, Enterococcus faecium MCL13, Lactobacillus sakei MCL14, and Lactobacillus acidophilus MCL15 were found to produce an antibacterial compound with inhibitory activity against the tested histamine-producing bacteria. The inhibitory activity of these bacteriocins obtained from the five LAB remained stable after incubation at pH 4.0-8.0 and heating for 10 min at $80^{\circ}C$; however, the bacteriocin activity was destroyed after treatment with papain, pepsin, proteinase K, ${\alpha}$-chymotrypsin, or trypsin. Meanwhile, these bacteriocins produced by the tested LAB strains also exhibited histamine-degradation ability. Therefore, these antimicrobial substances may play a role in inhibiting histamine formation in the fermented fish products and preventing seafood-related food-borne disease caused by bacterially generated histamine.

• Journal of Microbiology and Biotechnology
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• v.19 no.11
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• pp.1393-1400
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• 2009

A bacteriocin-producing strain PI80 was isolated from the gut of Penaeus indicus (Indian white shrimp) and identified as Streptococcus phocae PI80. The bacteriocin was purified from a culture supernatant to homogeneity as confirmed by Tricine SDS-PAGE. Reverse-phase HPLC analysis revealed a single active fraction eluted at 12.94 min, and MALDI-TOF mass spectrometry analysis showed the molecular mass to be 9.244 kDa. This molecular mass does not correspond to previously described streptococcal bacteriocins. The purified bacteriocin was named phocaecin PI80 from its producer strain, as this is the first report of bacteriocin production by Streptococcus phocae. The bacteriocin exhibited a broad spectrum of activity and inhibited important pathogens: Listeria monocytogenes, Vibrio parahaemolyticus, and V. fischeri. The antibacterial substance was also sensitive to proteolytic enzymes: trypsin, protease, pepsin, and chymotrypsin, yet insensitive to catalase, peroxidase, and diastase, confirming that the inhibition was due to a proteinaceous molecule (i.e., the bacteriocin), and not due to hydrogen peroxide or diacetyl. Phocaecin PI80 moderately tolerated heat treatment (up to $70^{\circ}C$ for 10 min) and resisted certain solvents (acetone, ethanol, and butanol). A massive leakage of $K^+$ ions from E. coli $DH5\alpha$, L. monocytogenes, and V. parahaemolyticus was induced by phocaecin PI80, as measured by Inductively Coupled Plasma Optical Emission Spectrometry (ICPOES). Therefore, the results of this study show that phocaecin PI80 may be a useful tool for inhibiting L. monocytogenes in seafood products that do not usually undergo adequate heat treatment, whereas the cells of Streptococcus phocae PI80 could be used to control vibriosis in shrimp farming.