• BMB Reports
• /
• v.35 no.2
• /
• pp.143-154
• /
• 2002

The structural and functional aspects of ervatamin B were studied in solution. Ervatamin B belongs to the $\alpha+\beta$ class of proteins. The intrinsic fluorescence emission maximum of the enzyme was at 350 nm under neutral conditions, and at 355 nm under denaturing conditions. Between pH 1.0-2.5 the enzyme exists in a partially unfolded state with minimum or no tertiary structure, and no proteolytic activity. At still lower pH, the enzyme regains substantial secondary structure, which is predominantly $\beta$-sheet conformation and shows a strong binding to 8-anilino-1-napthalene-sulfonic acid (ANS). In the presence of salt, the enzyme attains a similar state directly from the native state. Under neutral conditions, the enzyme was stable in urea, while the guanidine hydrochloride (GuHCl) induced equilibrium unfolding was cooperative. The GuHCl induced unfolding transition curves at pH 3.0 and 4.0 were non-coincidental, indicating the presence of intermediates in the unfolding pathway. This was substantiated by strong ANS binding that was observed at low concentrations of GuHCl at both pH 3.0 and 4.0. The urea induced transition curves at pH 3.0 were, however, coincidental, but non-cooperative. This indicates that the different structural units of the enzyme unfold in steps through intermediates. This observation is further supported by two emission maxima in ANS binding assay during urea denaturation. Hence, denaturant induced equilibrium unfolding pathway of ervatamin B, which differs from the acid induced unfolding pathway, is not a simple two-state transition but involves intermediates which probably accumulate at different stages of protein folding and hence adds a new dimension to the unfolding pathway of plant proteases of the papain superfamily.

• IMMUNE NETWORK
• /
• v.7 no.3
• /
• pp.141-148
• /
• 2007

Background: Anti-IgE mAb which binds circulating but not receptor-bound IgE has been shown to be effective in treatment for asthma and other allergic diseases. However, the mechanisms by which anti-IgE mAb influences the pathophysiological responses are remained to be illustrated. This study was undertaken to examine the therapeutic efficacy of non-anaphylactogenic anti-mouse IgE mAb using murine models of IgE-induced systemic fatal anaphylaxis. Methods: Active systemic anaphylaxis was induced by either penicillin V(Pen V) or OVA and passive systemic anaphylaxis was induced by either anaphylactogenic anti-mouse IgE or a mixture of anti-chicken gamma globulin (CGG) IgG1 mAb and CGG. The binding of the Fc portion of anti-IgE to CHO-stable cell line expressing mouse Fc ${\gamma}$ RIIb was examined using flow cytometry. Fc fragments of anti-IgE mAb were prepared using papain digestion. The expression of phosphatases in lungs were assessed by Western blotting and immunohistochemistry. Results: Anti-IgE mAb prevented IgE- and IgG-induced active and passive systemic fatal reactions. In both types of anaphylaxis, anti-IgE mAb suppressed antigen-specific IgE responses, but not those of IgG. Anti-IgE mAb neither prevented anaphylaxis nor suppressed the IgE response in Fc ${\gamma}$ RIIb-deficient mice. The Fc portion of anti-IgE mAb was bound to murine Fc ${\gamma}$ RIIb gene-transfected CHO cells and inhibited systemic anaphylaxis. Anti-IgE mAb blocked the anaphylaxis-induced downregulation of Fc ${\gamma}$ RIIb-associated phosphatases such as src homology 2 domain-containing inositol 5-phosphatase (SHIP) and phosphatase and tensin homologue deleted on chromosome ten (PTEN). Conclusion: Anti-IgE mAb prevented anaphylaxis by delivering nonspecific inhibitory signals through the inhibitory IgG receptor, Fc ${\gamma}$ RIIb, rather than targeting IgE.

• Reproductive and Developmental Biology
• /
• v.37 no.4
• /
• pp.175-183
• /
• 2013

Cathepsin B is abundantly expressed peptidase of the papain family in the lysosomes, and closely related to the cell degradation system such as apoptosis, necrosis and autophagy. Abnormal degradation of organelles often occurs due to release of cathepsin B into the cytoplasm. Many studies have been reported that relationship between cathepsin B and intracellular mechanisms in various cell types, but porcine embryos has not yet been reported. Therefore, this study evaluated the effect of cathepsin B inhibitor (E-64) on preimplantation developmental competence and quality of porcine embryos focusing on apoptosis and oxidative stress. The expression of cathepsin B mRNA in porcine embryos was gradually decreased in inverse proportion to E-64 concentration by using real-time RT-PCR. When putative zygotes were cultured with E-64 for 24 h, the rates of early cleavage and blastocyst development were decreased by increasing E-64 concentration. However, the rate of blastocyst development in $5{\mu}M$ treated group was similar to the control. On the other hand, both the index of apoptotic and reactive oxygen species (ROS) of blastocysts were significantly decreased in the $5{\mu}M$ E-64 treated group compared with control. We also examined the mRNA expression levels of apoptosis related genes in the blastocysts derived from $5{\mu}M$ E-64 treated and non-treated groups. Expression of the pro-apoptotic Bax gene was shown to be decreased in the E-64 treated blastocyst group, whereas expression of the anti-apoptotic Bcl-xL gene was increased. Taken together, these results suggest that proper inhibition of cathepsin B at early development stage embryos improves the quality of blastocysts, which may be related to not only the apoptosis reduction but also the oxidative stress reduction in porcine embryos.

• International Journal of Industrial Entomology and Biomaterials
• /
• v.9 no.2
• /
• pp.217-223
• /
• 2004

A cathepsin L-like cysteine protease, v-cath, encoded by the baculovirus has been shown to playa role in host liquefaction. We have identified a v-cath gene in the silkworm virus, Bombyx mori nuclear polyhedrosis virus (BmNPV) K1 strain. The 969 bp v-cath has an open reading frame of 323 amino acids. A putative cleavage site and catalytic sites were conserved in BmNPV-K1 v-cath. The predicted three-dimensional structure of BmNPV-K1 v-cath revealed that the overall fold of BmNPV-K1 v-cath is similar to that of other proteases of the papain family. The deduced amino acid sequence of BmNPV-K1 v-cath showed 98% and 97% protein sequence identity to BmNPV T3 strain and to Autographa californica nuclear polyhedrosis virus, respectively. The BmNPV-K1 v-cath differed at 4 amino acid positions from BmNPV T3. The v-cath gene in BmNPV-K1 genome is located on the EcoRV 6 kb and XhoI 9 kb fragments. Northern hybridization analysis of BmNPV K1 v-cath gene revealed that it is expressed late in infection.

• Korean Journal of Food Science and Technology
• /
• v.18 no.3
• /
• pp.234-240
• /
• 1986

Soybean hydrolysate (SHT) was prepared from defatted soybean by hydrolysing with papain and ${\alpha}-amylase$ and water sorption isotherms were determined as a function of proteolysis degree. The moisture content and B.E.T. value of SHT at a certain water activity $(A_w=0.80)$ increased lineraly with increasing degree of proteolysis. However, they changed drastically above 70% proteolysis. The water holding capacity of 78% SHT was similar to that of sorbito. The results indicate the increase of water sorption capacity is due to the release of polar groups through hydrolysis. Mizrahi equation generally gave the best fit for isotherms of SHT. Storage stability of intermediate moisture foods containing $5{\sim}10%$ SHT increased considerably, although some favorable characteristics decreased.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.22 no.2
• /
• pp.226-233
• /
• 1993

Enzymatic hydrolysates of food proteins (defatted soybean cake, egg albumin and casein) were tested for inhibitory activity against angiotensin-I converting enzyme (ACE). Food proteins were hydrolysed with complex enzyme, bromelain, alcalase, $\alpha$-chymotrypsin, trypsin, papain and pepsin by heating method. The hydrolysates obtained from the treatment of complex enzyme and bromelain showed the higher ACE inhibitory activity. ACE inhibitory activity of hydrolysates exhibited a tendency to be increased until 8hrs and increased with increment of concentration. The activity was also stable by heat treatment at 10$0^{\circ}C$ for 20min. Molecular weight of active fraction was about 1, 400 and defatted soybean cake hydrolysate below 1, 400 in case of defatted soybean cake hydrolysate treated with alcalase. Amino acid of the active fractions was abundant in Asp, Glu, Lys, lle, Leu, Ala and Val.

• Food Science of Animal Resources
• /
• v.43 no.1
• /
• pp.46-60
• /
• 2023

Slaughterhouse blood is a by-product of animal slaughter that can be a good source of animal protein. This research purposed to examine the functional qualities of the blood plasma from Hanwoo cattle, black goat, and their hydrolysates. Part of the plasma was hydrolyzed with proteolytic enzymes (Bacillus protease, papain, thermolysin, elastase, and α-chymotrypsin) to yield bioactive peptides under optimum conditions. The levels of hydrolysates were evaluated by 15% sodium dodecyl sulfate polyacrylamide gel electrophoresis. The antioxidant, metal-chelating, and angiotensin I-converting enzyme (ACE) inhibitory properties of intact blood plasma and selected hydrolysates were investigated. Accordingly, two plasma hydrolysates by protease (pH 6.5/55℃/3 h) and thermolysin (pH 7.5/37℃/3-6 h) were selected for analysis of their functional properties. In the oil model system, only goat blood plasma had lower levels of thiobarbituric acid reactive substances than the control. The diphenyl picrylhydrazyl radical scavenging activity was higher in cattle and goat plasma than in proteolytic hydrolysates. Ironchelating activities increased after proteolytic degradation except for protease-treated cattle blood. Copper-chelating activity was excellent in all test samples except for the original bovine plasma. As for ACE inhibition, only non-hydrolyzed goat plasma and its hydrolysates by thermolysin showed ACE inhibitory activity (9.86±5.03% and 21.77±3.74%). In conclusion, goat plasma without hydrolyzation and its hydrolysates can be a good source of bioactive compounds with functional characteristics, whereas cattle plasma has a relatively low value. Further studies on the molecular structure of these compounds are needed with more suitable enzyme combinations.

• Food Science of Animal Resources
• /
• v.44 no.3
• /
• pp.533-550
• /
• 2024

Peptides with bioactive effects are being researched for various purposes. However, there is a lack of overall research on pork-derived peptides. In this study, we reviewed the process of obtaining bioactive peptides, available analytical methods, and the study of bioactive peptides derived from pork. Pepsin and trypsin, two representative protein digestive enzymes in the body, are hydrolyzed by other cofactors to produce peptides. Bicinchoninic acid assay, sodium dodecyl sulfate-polyacrylamide gel electrophoresis, chromatography, and in vitro digestion simulation systems are utilized to analyze bioactive peptides for protein digestibility and molecular weight distribution. Pork-derived peptides mainly exhibit antioxidant and antihypertensive activities. The antioxidant activity of bioactive peptides increases the accessibility of amino acid residues by disrupting the three-dimensional structure of proteins, affecting free radical scavenging, reactive oxygen species inactivation, and metal ion chelating. In addition, the antihypertensive activity decreases angiotensin II production by inhibiting angiotensin converting enzyme and suppresses blood pressure by blocking the AT1 receptor. Pork-derived bioactive peptides, primarily obtained using papain and pepsin, exhibit significant antioxidant and antihypertensive activities, with most having low molecular weights below 1 kDa. This study may aid in the future development of bioactive peptides and serve as a valuable reference for pork-derived peptides.

• Safety and Health at Work
• /
• v.15 no.2
• /
• pp.129-138
• /
• 2024

The COVID-19 pandemic has led to a significant surge in glove usage, as recommended by the World Health Organization. Despite efforts to ensure the quality and safety of gloves, glove-associated skin diseases such as hand dermatitis have become ubiquitous, particularly among health care workers. This review discusses the prevalence, causes, and risk factors of hand dermatitis, as well as research efforts in medical gloves in the past decade to overcome glove-related hand dermatitis. Research papers from 2013 to 2022 were reviewed, selecting only 49 relevant papers from the Ovid, PubMed, and Scopus databases. The average prevalence of hand dermatitis among health care workers increased from 21.08% to 37.24% upon the impact of the COVID-19 pandemic. The cases are likely due to allergies to latex proteins, rubber additives, and accelerators commonly found in gloves. Using alternatives to latex gloves, such as accelerator-free and latex-free glove options, can help reduce allergy-induced hand dermatitis. Strict hand hygiene practices, such as frequent hand washing and the use of sanitizers, are also contributing factors in contracting hand dermatitis. Over the past decade, glove research advancements have focused mainly on reducing or immobilizing latex proteins. These include the use of biodegradable dialdehyde, sodium alginate, arctigenin, bromelain, papain, UV-LED, prototype photoreactors, and structure-modified nanosilica with silane A174. Two effective hand dermatitis preventive measures, i.e. an additional layer of glove liners and the use of gentle alcohol-based hand sanitizer, were recommended. These advancements represent promising steps towards mitigating hand dermatitis risks associated with glove usage.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.39 no.1
• /
• pp.8-13
• /
• 2010

The angiotensin converting enzyme (ACE) inhibition effect of soybean protein isolate hydrolysate was studied using protease. Soybean protein isolate was hydrolysed by seven enzymes (Alcalase 2.4 L, Flavourzyme 500 MG, GC 106, Multifect Neutral, Neutrase 0.8 L, Papain 30,000 and Protamex), enzyme concentrations (0, 0.5, 1.0 and 1.5%), at various hydrolysis times (0, 1, 2, 3, 4, 5 and 6 hr) and suspension concentrations (1, 5, 7, 10 and 15%). Absorbance at 280 nm, brix and ACE inhibitory activity of soybean protein isolate hydrolysates were investigated. Absorbance at 280 nm and brix of Alcalase 2.4 L treatment were higher than other enzyme treatments. The optimum condition of hydrolysis was Alcalase 2.4 L, 1% enzyme concentration, 5% suspension concentration for 4 hr. $IC_{50}$ value of ACE inhibitory activity of soybean protein isolate hydrolysate was $79.94 {\mu}g/mL$. These results suggest that soybean isolate protein hydrolysate from Alcalase 2.4 L may be of benefit for developing antihypertensive therapeutics.