• BMB Reports
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• 제34권1호
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• pp.33-38
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• 2001

The human PTK6 (also known as Brk) polypeptide, which is deduced from its full-length cDNA, represents a non-receptor protein tyrosine kinase (PTK). It contains SH3, SH2, and tyrosine kinase catalytic domains that are closely related to Src family members. We generated an antihuman PTK6 antibody by immunizing rabbits with a PTK6-specific oligopeptide conjugated to BSA, which corresponds to 11 amino acid residues near the C-terminus. An immunoblot analysis with the antibody detected an expected 52-kDa band in various mammalian transformed cell lines. Immunoprecipitation and immunoblot analyses demonstrated that PTK6 is phosphorylated on the tyrosine residues) and interacts with approximately a 23-kDa tyrosine-phosphorylated polypeptide (most likely a substrate of PTK6) in breast carcinoma T-47D cells. An immunofluorescence analysis demonstrated that PTK6 is localized throughout the cytoplasm of T-47D cells. These results support a possible role for PTK6 in the intracellular signal transduction through tyrosine phosphorylation.

• Archives of Pharmacal Research
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• 제27권2호
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• pp.206-216
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• 2004

The functional role of protein carboxylmethylation (PCM) has not yet been clearly elucidated in the tissue level. The biochemical feature of PCM in porcine spleen was therefore studied by investigating the methyl accepting capacity (MAC) of natural endogenous substrate proteins for protein carboxyl O-methyltransferase (PCMT) in various conditions. Strong acidic and alkaline-conditioned (at pH 11.0) analyses of the MAC indicated that approximately 65％ of total protein methylation seemed to be mediated by spleen PCMT. The hydrolytic kinetics of the PCM products, such as carboxylmethylesters (CMEs), under mild alkaline conditions revealed that there may be three different kinds of CMEs [displaying half-times (T$_{1}$2/) of 1.1 min (82.7％ of total CMEs), 13.9 min (4.6％), and 478.0 min (12.7％)], assuming that the majority of CME is base-labile and may be catalyzed by class I PCMT. In agreement with these results, several natural endogenous substrate proteins (14, 31 and 86 kDa) were identified strikingly by acidic-conditioned electrophoresis, and their MAC was lost upon alkaline conditions. On the other hand, other proteins (23 and 62 kDa) weakly appeared under alkaline conditions, indicating that PCM mediated by class II or III PCMT may be a minor reaction. The MAC of an isolated endogenous substrate protein (23-kDa) was also detected upon acidic-conditioned electrophoresis. Therefore, our date suggest that most spleen PCM may be catalyzed by class I PCMT, which participates in repairing aged proteins.

• 한국균학회지
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• 제23권1호통권72호
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• pp.46-52
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• 1995

화경버섯의 자실체로부터 PAGE로 한 렉틴을 정제하고, LJAP(Lampteromyces japonicus antibacterial protein)라 이름 붙였다. LJAP는 17-kDa의 서브유닛트가 모여서 된 백 kDa이 넘는 회합 단백질이였다. 이 단백질은 아미노산 분석결과 세린, 글리신, 산성 아미노산의 함량이 높았다. LJAP는 대장균중 특히 JM 109, K 12, HB 101, JW 380에 대한 항세균작용이 뛰어났다. 한편, 항세균활성은 당단백질인 asialofetuin에 의하여 크게 억제되었다. 본 당단백질은 화경버섯에서 처음으로 얻어진 항세균활성과 적혈구 응집활성을 가진 렉틴이다.

• BMB Reports
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• 제34권4호
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• pp.293-298
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• 2001

Tryptic activation of the 130-kDa Bacillus thuringiensis Cry4B $\delta$-endotoxin produced protease-resistant products of ca. 47 kDa and ca. 21 kDa. The 21-kDa fragment was identified as the N-terminal five-helix bundle (${\alpha}1-{\alpha}5$,) which is a potential candidate for membrane insertion and pore formation. In this study, we constructed the recombinant clone over-expressing this putative pore-forming (PPF) fragment as inclusion bodies in Escherichia coli. The partially purified inclusions were composed of a 23-kDa protein, which cross-reacted with Cry4B antibodies, and whose N-terminus was identical to that of the 130-kDa protein. Dissimilar to protoxin inclusions, the PPF inclusions were only soluble when the carbonate buffer, pH 9.0, was supplemented with 6 M urea. After renaturation via a stepwise dialysis, the refolded PPF protein appeared to exist as an oligomer and was structurally stable upon trypsin treatment. Unlike the 130kDa protoxin, the refolded protein was able to release entrapped glucose from liposomes, and showed comparable activity to the full-length activated toxin, although it lacks larvicidal activity These results, therefore, support the notion that the PPF fragment that consists of ${\alpha}1-{\alpha}5$ of the activated Cry4B toxin is involved in membrane pore-formation.

• BMB Reports
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• 제39권6호
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• pp.782-787
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• 2006

A new protein was cloned and identified as the sixth subunit of Choristoneura fumiferana origin recognition complex (CfORC6). The newly identified 43 kDa protein CfORC6 is much bigger than DmORC6 (25.7 kDa) and HsORC6 (28.1 kDa), though it's 23.85% identical to DmORC6 and 23.81% identical to HsORC6. Although the molecular weight of CfORC6 is close to ScORc6 (50 kDa), CfORC6 is only 14.03% identical to ScORC6. By alignment, it was found that the N-terminal of CfORC6 has about 30% identities with other ORC6s, but about 100aa of C-terminal of CfORC6 has no identity with other ORC6s. Like ScORC6, CfORC6 has many potential phosphorylation sites, (S/T)PXK. Like DmORC6, CfORC6 has leucine-rich region in the relevant site. Northern Blot showed that CfORC6 mRNA is about 2,000nt. Southern Blot confirmed that there is one copy of CfORC6 gene in spruce budworm genome. Western blot showed that infection of Cf124T cells with CfMNPV didn't affect the expression levels of CfORC6, at least up to 26 hr post infection.

• 아시안잔디학회지
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• 제4권1호
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• pp.12-23
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• 1990

The chlorophyll-protein complexes were separated from thylakoid membranes of Spinach oleracea and Zoysia japonica by two gel Systems of LiDodSO4-PAGE and LiDodSo4/Urea- PAGE under nondenaturing conditions. Seven chlorophyll~protein complexes of CPI*, CPI, CPII*. CP47, CP43, CP29 and CPII were fractionated from both S,oleracea and Zjaponica by LiDodSO4-PAGE. CPI, CP47 and CP43 contained more chlorophyll a than chlorophyll b. The patterns of their absorption spectra at room temperature were similliar to that of chlorophyll a, judging by their UV-spedtroscopy. On the other hand, CPII* and CPII contained approximately equim-olar quantities of chlorophyll a and b. Additional five chlorophyll-protein complexes not separated in the LiDodSO4-PAGE system were electrophoretically isolated from both S, oleracea and Zjaponica by LiDodSO4/Urca-PAGE. The chlorophyll-protein complex just above LRCII $\alpha$in the gel appears CCII-RC separeted recently. 23 kDa and 20 kDa cho-protein complexes is probably LHCIa and LHCIb as judged from their molecular weight. Two novel chlorophyll~protein complexes designated "CPI7" and "CPI6" were fractionate by this gel system. Their molecular weights respectively. Although the stoichiometry of their components and their roles in thylakoid membranes are not apparant, It is thought that they are another kinds of LHCI.other kinds of LHCI.

• BMB Reports
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• 제29권3호
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• pp.236-240
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• 1996

A 23-kDa molecular mass of antioxidant protein was purified from human liver. This protein exhibited the preventive effect against the inactivation of glutamine synthetase by a metal-catalyzed oxidation system. This antioxidant activity was supported by a thiol-reducing equivalent such as dithiothreitol in a similar manner to that of the 25-kDa thiol-specific antioxidant protein (TSA) from human red blood cells (HR). However, a thioredoxin-linked peroxidase activity of thiol-specific antioxidant protein of human liver (HLTSA) (0.91 ${\mu}mol/min/nmol$ of HLTSA) was much lower than that of thiol-specific antioxidant protein of human red blood cells (HRTSA) (16.4 ${\mu}mol/min/nmol$ of HRTSA). This HLTSA is also immnologically distinct from HRTSA Amino acid sequences of the three tryptic peptides (P1, P2, P3) of HLTSA were found to be completely homologous to segments of the known Mer5-like protein, which belongs to the known TSA family.

• Parasites, Hosts and Diseases
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• 제26권3호
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• pp.163-168
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• 1988

스파르가눔증을 혈청학적으로 진단하기 위하여 효소면역측정법을 실시할 경우, 그 민감도와 특이도가 높다고 이미 보고되었다. 실제로 조직기생충 감염이 의심되는 환자에 대하여 특이 IgG항체가를 일상적으로 검사하면 중추신경계 환자중에서 뇌스파르가눔증은 드물지 않게 발견할 수 있다. 그러나 혈청학적 진단에 이용되는 스파르가눔 조항원(조항원)은 조충증(조충증), 유구낭미충증이나 포충증 환자의 혈청과 비특이적인 교차반응을 일으키는 경우가 있다. 이러한 교차반응의 문제를 해결하려면 우선 스파르가눔 항원의 구성 단백질이 환차혈청과 반응하는 양상을 알아야 할 필요가 있다. 이 연구에서는 외과적으로 스파르가눔증을 확인한 환자 15명에서 얻은 혈청이 스파가눔의 생리식염수 추출액의 항원단백질중 어느 분획과 반응하는지 검토하였다. 그리고 뇌유구낭미충증 환자 24명(그중 8명은 효소면역측정법으로 교차반응이 있었음)의 혈청과 교차반응을 일으키는 단백질 분획을 관찰하였다. 스파르가눔충체의 생리식염수 추출액을 10∼15% linear gradient gel에서 SDS-폴리아크릴아마이드 전기영동을 실시하여 단백질대 30개를 구별할 수 있었다. 분리한 단백질(대)를 nitrocellulose 종이에 옮긴후 스파르가눔증 환자 혈청 및 conjugate와 차례로 반응시키고 발색반응을 일으킨 결과 (효소면역 전기영동이적법, immunoblot), 스파르가눔 항원단백질중 29kDa 및 36kDa가 가장 많이 또 가장 진하게 반응한 것이어서 민감하고 항원성이 높은 단백질 분획이라고 판단하였다. 그리고 위의 단백질 이외에도 158kDa, 130kDa, 107kDa, 78kDa, 72kDa, 52kDa, 23kDa, 21kDa, 15kDa 및 6kDa 등에도 반응이 있었다. 유구낭충증 환자 24명의 혈청중 스파르가눔 항원에 혈청학적 교차반응이 있었던 혈청은 36kDa 및 29kDa 단백질에 반응하고 있어 이 단백질이 스파르가눔의 종 특이(종특이)단백질 항원은 아닌 것으로 판단되나 그 성질에 대해서는 앞으로 더 추구할 가치가 있다고 생각한다.

• 생명과학회지
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• 제22권11호
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• pp.1487-1492
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• 2012

복숭아는 오래 전부터 알레르기를 일으키는 식품으로 알려져 있으나 특정 식품과의 교차반응에 대한 연구는 부족한 실정이다. 본 연구에서는 한국에서 재배되고 있는 복숭아, 앵두, 고추의 단백질을 추출하여 복숭아 알레르기를 가진 환자가 앵두와 고추에 대해 교차반응성을 일으키는지 확인하고 이 단백질들의 소화효소처리에 따른 안정성을 조사하였다. 복숭아, 앵두 및 고추 단백질 추출물은 Tricine-SDS-PAGE상에서 3 kDa부터 26 kDa 이상까지 넓은 범위의 단백질 분포를 보였으나 각기 다른 패턴을 가지는 것을 확인하였다. 복숭아 단백질의 항원성을 확인하기 위해 복숭아 민감성 환자의 혈청과의 IgE반응성을 확인한 결과, 환자 혈청은 모두 복숭아의 주요 항원성 단백질 lipid transfer protein로 예상되는 9 kDa 부근에서 강한 IgE결합력을 보였으며 또한 9 kDa 단백질이 anti-LTP1 polyclonal antibody에 의해 검출되는 것을 확인하였다. 앵두와 고추 단백질 추출물은 23 kDa 부근에서의 IgE결합력이 9 kDa과의 반응성보다 크게 나타났다. 복숭아, 앵두 및 고추의 소화효소에 대한 안정성을 SDS-PAGE 상에서 확인한 결과, 복숭아, 앵두 및 고추의 항원성 단백질은 인공 위액 및 장액에 의해 완전히 분해되지 않아 알레르기를 유발할 잠재성이 있는 것을 확인할 수 있었다. 본 연구 결과를 바탕으로, 복숭아, 앵두 및 고추 단백질 추출물이 소화효소처리에 안정성을 가지는 특성을 가지며 복숭아 알레르기 증상을 가지는 사람에게 앵두 및 고추는 교차반응성을 일으킬 가능성이 크다는 것을 확인할 수 있었다.

• Parasites, Hosts and Diseases
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• 제48권2호
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• pp.151-155
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• 2010

Allergen extracts from dust mites and cockroaches commonly found in Korean homes were used to evaluate their enzymatic activity as they are believed to influence allergenicity. Allergen extracts were prepared from 3 dust mite species (Dermatophagoides farinae, D. pteronyssinus, and Tyrophagus putrescentiae) and 3 cockroach species (Blattella germanica, Periplaneta americana, and P. fuliginosa) maintained in the Korea National Arthropods of Medical Importance Resource Bank. Proteins were extracted in PBS after homogenization using liquid nitrogen. The activities of various enzymes were investigated using the API Zym system. No significant difference in phosphatase, lipase, or glycosidase activity was observed among the 6 allergen extracts, but much difference was observed in protease activity. Protease activity was assessed in more detail by gelatin zymography and the EnzChek assay. Extract from T. putrescentiae showed the highest protease activity, followed by those of the cockroach extracts. Extracts from D. farinae and D. pteronyssinus showed only weak protease activity. Gelatinolytic activity was detected mainly in a 30-kDa protein in D. farinae, a 28-kDa protein in D. pteronyssinus, a > 26-kDa protein in T. putrescentiae, a > 20-kDa protein in B. germanica, and a > 23-kDa protein in P. americana and P. fuliginosa. The information on various enzymatic activities obtained in this study may be useful for future studies. In particular, the strong protease activity found in cockroach extracts could contribute to sensitization to cockroach allergens, which is known to be associated with the development of asthma.