• KSBB Journal
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• 제32권1호
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• pp.71-82
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• 2017

To verify anti-diabetic effect of oligopeptide with His-Pro repeats (mHP peptide), the oligopeptide was first secreted and optimized using the secretion vector, pRBAS with alkaline protease gene promoter and the signal sequence in Bacillus subtilis and directly the anti-diabetic effect of the mHP peptide was investigated in insulinoma cell, RINm5F cell line. The oligopeptide gene was obtained by annealing oligonucleotides with repeated His-Pro sequence and finally was constructed as 18 dipeptides (108 bp and 4.0 kDa) coding gene, named oligopeptide with His-Pro repeats (mHP peptide) to make cyclo(His-Pro) known to be anti-diabetic effects. The region encoding the oligopeptide gene was subcloned into the pRBAS secretion vector (E.coli-Bacillus shuttle vector) after PCR amplification using the designed primers including initiation and termination codons and His tag, named pRBAS-mHP (6.56 kb). To optimize secretion of the oligopeptide, various culture conditions were investigated in Bacillus subtilis LKS. As a result, the secreted oligopeptide was maximally measured (approximately $59.6{\mu}g/mL$) in 3 L batch culture and the highest secretion was achieved at $30^{\circ}C$, PY medium, and carbon sources (particularly barley and glycerol). In the RINm5F cells treated with 2 mM STZ, the oligopeptide treatment (0.1 mg/mL) restored the cell viability (10%) and reduced the nitric oxide (NO) generation (35%) and DNA fragmentation (90%). And also, insulin secretion level was increased to 17% higher than in STZ-treated RINm5F cells. These results suggest that the oligopeptide with His-Pro repeats could be a candidate material for anti-diabetic agent against STZ-induced diabetes.

• 한국식품조리과학회지
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• 제23권5호
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• pp.644-649
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• 2007

In this study a purified protein was prepared from pork meat. The product consisted of 0.5% moisture, 3.0% ash, 5.5% ether extract and 88.7% crude protein. Also, a meat oligopeptide mixture was prepared from a pepsin digest of the protein preparation. The two preparations were colorless and odorless powders with low fat contents. The nutritive values of the pork meat protein and oligopeptide mixture were estimated by two methods, one using biological value(BV) and the other employing net protein utilization(NPU) by the nitrogen balance method. The meat oligopeptide mixture showed an excellent nutritive value by both methods. The true digestibilites of both the pork meat protein and the oligopeptide mixture were more than 98%. The above results indicate that the oligopeptide mixture is an excellent material as a dietary nitrogen source for many purposes.

• Bulletin of the Korean Chemical Society
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• 제31권5호
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• pp.1262-1266
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• 2010

In this study, we investigated the use of liquid crystals to selectively detect the activity of enzymes at interfaces decorated with oligopeptide-based membranes. We prepared a mixed monolayer of tetra(ethylene glycol)-terminated lipids and carboxylic acid-terminated lipids at the aqueous-liquid crystal (LC) interface. The 17 amino-acid oligopeptide SNFKTIYDEANQFATYK was then immobilized onto this mixed monolayer through N-hydroxysuccinimide-activation of the carboxylic acid groups. We examined the orientational behavior of nematic 4-cyano-4'-pentylbiphenyl (5CB) after conjugation of the 17 amino-acid oligopeptide with the mixed monolayer assembled at the interface. Immobilization of the oligopeptide caused orientational transitions in 5CB, with a change from homeotropic (perpendicular) to tilted alignment, which was primarily due to the reorganization of the monolayer. The orientation of the 5CB molecules returned to its homeotropic state after contacting the interface containing ${\alpha}$-chymotrypsin, which can cleave the immobilized oligopeptide. Control experiments confirmed that the enzymatic activity of ${\alpha}$-chymotrypsin triggered the ordering transitions in the LC. These results suggest that the LC can provide a facile method for selective detection of enzymatic activity.

• 대한화학회지
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• 제21권6호
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• pp.445-448
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• 1977

단백질 분해효소인 ${\alpha}$-chymotrypsin이 식품발색제의 존재하에 어떻게 oligopeptide에 작용하여 분해하는가를 알기 위하여 본 실험을 실시하였다. 1. Oligopeptide인 Asp-Arg-Val-Tyr-Ile-His-Pro-D-Ala(8-D-Ala${\cdot}$angiotensin II)의 융점은 210 ~ $212^{\circ}C$, 분자식은 $C_{44}H_{67}N_{13}O_{12}{\cdot}2CH_3COOH{\cdot}H_2O$, 분자량은 970.08이었다. 2. 산으로 가수분해 하였을 때 몰 비율은 Asp : 1.01, Arg : 1.03, Val : 1.00, Tyr :40.94, Ile : 1.00, His : 1.05, Pro : 1.04, D-Ala : 1.03이였다. 3. (8-D-Ala)angiotensin II의 oligopeptide에 ${\alpha}$-Chymotrypsin의 작용은 Tyr-Ile 결합에만 분해작용을 하였다. 4. 식품착색제의 첨가는 paper chromatogram 방법에 의해서 추정할때 oligopeptide, (8-D-Ala) angiotensin II에 대한 ${\alpha}$-Chymotrypsin의 저해작용에 아무런 영향을 끼치지 않았음을 볼 수 있다.

• 한국식품영양학회지
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• 제25권1호
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• pp.116-122
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• 2012

The objective of this study was to address the issues associated with the solubility of the pork meat oligopeptide, while maintaining its original nutritional value and improving its digestibility. The pork meat oligopeptide was used to produce an oral liquid supplement that was contained in a 200 $m{\ell}$ can. The formulation was designed to satisfy 20% of the daily recommended nutrition intake of an adult male aged between 20 and 29. Analysis of the quality characteristics showed that this formulation was highly homogenized as an oral liquid supplement with advanced solubility. In addition, based on the viscosity, pH, color value, turbidity, and brix, the product was shown to advanced processing quality with great solubility; however, there was some concern that the taste would be deteriorated due to the bitter taste of the peptide. Thus, further studies need to be performed before this formulation can be commercialized.

• Bulletin of the Korean Chemical Society
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• 제17권2호
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• pp.131-138
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• 1996

The conformational transition of oligopeptide multimer,-(HPPHPPP)n-, is studied (H:hydrophobic amino acid, P:hydrophilic amino acid). The helix/coil transitions are detected in the multimer. The transition depends on the number of amino acid in the sequence, the concentration of the oligopeptide, and temperature which affects helix stability constant (${\xi}$) and hydrophobic interaction parameter (wj). In the thermodynamic equilibrium system jA${\rightarrow}$Aj (where A stands for oligopeptide monomer), Skolnick et al., explained helix/coil transition of dimer by the matrix method using Zimm-Bragg parameters ${\xi}$ and $\sigma$ (helix initiation constant). But the matrix method do not fully explain dangling H-bond effects which are important in oligopeptide systems. In this study we propose a general theory of conformational transitions of oligopeptides in which dimer, trimer, or higher multimer coexists. The partition of trimer is derived by using zipper model which account for dangling H-bond effects. The transitions of multimers which have cross-linked S-S bonds or long chains do not occur, because they keep always helical structures. The transitions due to the concentration of the oligopeptides are steeper than those due to the chain length or temperature.

• 대한화장품학회지
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• 제32권1호
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• pp.7-15
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• 2006

본 연구에서는 발아 검은 쌀로부터 분리한 올리고펩타이드($Oligosproutin^{(R)}$)의 피부 탄력 개선 효과에 대하여 연구하였다. 올리고펩타이드가 각질형성세포의 유전자 발현에 미치는 영향을 알아보고자 DNA microarray를 수행하였다. 각질형성세포에 올리고펩타이드를 처리하여 유전자의 발현이 2배 이상 증가하는 유전자는 745개이고, 2배 이상 감소하는 유전자는 1011개로 나타났다. 이 중 hyaluronan synthase 2 (HAS2)의 유전자 발현이 2배 이상 증가함을 확인하였다. 올리고펩타이드를 처리한 각질형성세포에서 세포활성 증가, HAS2 유전자 발현 증가, 세포내 항산화 효과를 확인하였다. 올리고펩타이드를 함유한 O/W 에멀젼을 이용한 임상실험에서 피부의 탄력 개선 효과를 확인하였다. 본 연구를 통하여 발아 검은 쌀로부터 분리한 올리고펩타이드는 피부 탄력 개선을 주는 항노화 화장품 개발에 응용될 수 있을 것이라 기대된다.

• Food Science and Biotechnology
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• 제27권6호
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• pp.1791-1799
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• 2018

In this study, the immunomodulatory activity of oligopeptide (CP) derived from solid-state fermented cottonseed meal were investigated in immunosuppressed BALB/c mice models by treatment with cyclophosphamide (CY). Results indicated that oligopeptide increased the thymus and spleen indices of CY-treated mice. The count of plague forming cells (PFC) and the content of half serum hemolysis ($HC_{50}$) in immunosuppressive mice were restored to the normal level in CP-10 and CP-20 groups while the cytokines interleukin (IL)-2, IL-6, and tumor necrosis factor alpha (TNF-${\alpha}$) were increased significantly in CP-20 group. Similar increasing the immunoglobulin of IgG and IgM content in the serum of CP-10 group were also observed. These findings indicated that oligopeptide derived from solid-state fermented cottonseed meal had a strong immune-enhancing activity as well as a protective effect against immunosuppression induced by cyclophosphamide in mice.

• 한국축산식품학회지
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• 제38권6호
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• pp.1144-1154
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• 2018

Both the calcium and collagen in bone powder are hard to be absorbed by the body. Although enzymatic hydrolysis by protease increased the bio-availability of bone powder, it was a meaningful try to further increase $Ca^{2+}$ release, oligopeptide formation and antioxidant activity of the sheep bone hydrolysate (SBH) by lactic acid bacteria (LAB) fermentation. Lactobacillus helveticus was selected as the starter for its highest protease-producing ability among 5 tested LAB strains. The content of liberated $Ca^{2+}$ was measured as the responsive value in the response surface methodology (RSM) for optimizing the fermenting parameters. When SBH (adjusted to pH 6.1) supplemented with 1.0% glucose was inoculated 3.0% L. helveticus and incubated for 29.4 h at $36^{\circ}C$, $Ca^{2+}$ content in the fermented SBH significantly increased (p<0.01), and so did the degree of hydrolysis and the obtaining rate of oligopeptide. The viable counts of L. helveticus reached to $1.1{\times}10^{10}CFU/mL$. Results of Pearson correlation analysis demonstrated that LAB viable counts, $Ca^{2+}$ levels, obtaining rates of oligopeptide and the yield of polypeptide were positively correlated with each other (p<0.01). The abilities of SBH to scavenge the free radicals of DPPH, OH and ABTS were also markedly enhanced after fermentation. In conclusion, L. helveticus fermentation can further boost the release of free $Ca^{2+}$ and oligopeptide, enhance the antioxidant ability of SBH. The L. helveticus fermented SBH can be developed as a novel functional dietary supplement product.

• Journal of Veterinary Science
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• 제21권6호
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• pp.88.1-88.13
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• 2020

Background: Listeria monocytogenes is a gram-positive bacterium that causes listeriosis mainly in immunocompromised hosts. It can also cause foodborne outbreaks and has the ability to adapt to various environments. Peptide uptake in gram-positive bacteria is enabled by oligopeptide permeases (Opp) in a process that depends on ATP hydrolysis by OppD and F. Previously a putative protein Lmo2193 was predicted to be OppD, but little is known about the role of OppD in major processes of L. monocytogenes, such as growth, virulence, and biofilm formation. Objectives: To determine whether the virulence traits of L. monocytogenes are related to OppD. Methods: In this study, Lmo2193 gene deletion and complementation strains of L. monocytogenes were generated and compared with a wild-type strain for the following: adhesiveness, invasion ability, intracellular survival, proliferation, 50% lethal dose (LD₅₀) to mice, and the amount bacteria in the mouse liver, spleen, and brain. Results: The results showed that virulence of the deletion strain was 1.34 and 0.5 orders of magnitude higher than that of the wild-type and complementation strains, respectively. The function of Lmo2193 was predicted and verified as OppD from the ATPase superfamily. Deletion of lmo2193 affected the normal growth of L. monocytogenes, reduced its virulence in cells and mice, and affected its ability to form biofilms. Conclusions: Deletion of the oligopeptide transporter Lmo2193 decreases the virulence of L. monocytogenes. These effects may be related to OppD's function, which provides a new perspective on the regulation of oligopeptide transporters in L. monocytogenes.