• 제목/요약/키워드: beta subunits

검색결과 190건 처리시간 0.03초

Purification and Characterization of Two Novel $\beta$-D-Glucuronidases Converting Glycyrrhizin to 18$\beta$-Glycyrrhetinic Acid-3-O-$\beta$-D-Glucuronide from Streptococcus LJ-22

  • PARK HYE-YOUNG;KIM NA-YOUNG;HAN MYUNG JOO;BAE EUN-AH;KIM DONG-HYUN
    • Journal of Microbiology and Biotechnology
    • /
    • 제15권4호
    • /
    • pp.792-799
    • /
    • 2005
  • Two novel $\beta$-glucuronidases, which metabolize glycyrrhizin (GL) to 18$\beta$-glycyrrhetinic acid-3-O-$\beta$-D-glucuronide (GAMG), were purified from Streptococcus LJ-22 isolated from human intestinal microflora. $\beta$-Glucuronidases I and II were purified to apparent homogeneity, using a combination of ammonium sulfate fractionation, butyl toyopearl, Q-Sepharose, hydroxyapatite Ultrogel, and GL-attached Sepharose column chromatographies, with the final specific activities of 137 and 190 nmole/min/mg, respectively. The molecular sizes of both $\beta$-glucuronidases were found to be 140 kDa by gel filtration, and they consisted of two identical subunits (M.W. 67 kDa by SDS-PAGE). $\beta$-Glucuronidases I and II showed optimal activity at pH 7.0 and pH 6.5, respectively. Both purified enzymes were potently inhibited by $Cu^{2+}$ and PCMS, and had maximum activity on glycyrrhizin, but did not hydrolyze p-nitrophenyl-$\beta$-glucuronides, baicalin, or GAMG These findings suggest that the biochemical properties and substrate specificities of these enzymes are different from those of the previously purified $\beta$-glucuronidases. This is the first reported purification of sugar (not aglycone)-recognizing $\beta$-glucuronidases from intestinal bacteria.

신생 백서의 저산소 허혈 뇌손상에서 Transforming Growth Factor-β1 투여에 따른 Nitric Oxide Synthase 이성체와 N-methyl-D-aspartate 수용체 아단위의 발현 (Expression of nitric oxide synthase isoforms and N-methyl-D-aspartate receptor subunits according to transforming growth factor-β1 administration after hypoxic-ischemic brain injury in neonatal rats)

  • 고혜영;서억수;김우택
    • Clinical and Experimental Pediatrics
    • /
    • 제52권5호
    • /
    • pp.594-602
    • /
    • 2009
  • 목 적 : $TGF-{\beta}1$는 흥분독성을 억제시키고 질소 산화물 생성 억제를 통한 신경세포 보호 효과가 있다고 알려져 있지만 주산기저산소 허혈 뇌손상에서 그 기전은 아직도 확실히 밝혀져 있지 않고 있다. 따라서 이번 연구에서는 신생 백서의 저산소 허혈 뇌손상에서 산화질소로 인한 신경독성 및 글루탐산염에 의한 흥분독성과 $TGF-{\beta}1$의 관계를 보고자 하였다. 방 법 : 생체외 실험으로 재태 기간 19일된 태아 백서의 대뇌피질 세포를 배양하여 1% O2 배양기에서 저산소 상태로 뇌세포손상을 유도하여 저산소군(Hypoxia), 저산소 손상 30분 전 $TGF-{\beta}1$ (1, 5, 10 ng/mL) 투여군(H+$TGF-{\beta}1$)으로 나누어 정상 산소군 (Control)과 비교하였다. 생체 내 실험은 생후 7일된 백서의 좌측 총 경동맥을 결찰한 후 저산소 (7.5% O2) 상태로 2시간 노출시켜서, 저산소 허혈 뇌손상을 유발하였다. 아무런 처치도 하지 않은 정상 대조군(Control), 경동맥 노출 후 봉합 시술만 시행한 정상 Sham 수술군(Sham-OP), 손상 30분 전 생리식염수를 주입 후 경동맥 결찰과 저산소 노출을 시행한 저산소 허혈 대조군(HI+ Vehicle), 손상 30분 전 $TGF-{\beta}1$을 대뇌로 투여하고 경동맥 결찰과 저산소 노출을 시행한 저산소 허혈 $TGF-{\beta}1$ 투여군(HI+$TGF-{\beta}1$)으로 나누어 비교분석하였다. 흥분독성과의 관련을 알아보기 위하여 NMDA 수용체 아단위를 이용하였고, 질소산화물과의 관련을 알아보기 위해 iNOS, eNOS 및 nNOS를 이용하여 western blotting과 실시간 중합효소연쇄반응을 하였다. 결 과 : 생체 외 실험에서 iNOS의 발현은 정상 산소군과 저산소군 간에 차이가 없었으며, $TGF-{\beta}1$ 투여군에서는 발현이 증가하였으며 이는 농도와는 상관성이 없었다. eNOS, nNOS의 발현은 1 ng/mL의 $TGF-{\beta}1$ 투여군에서 저산소군보다 감소하였다. 생체 내 실험에서는 iNOS와 iNOS mRNA의 발현은 $TGF-{\beta}1$ 투여한 후 저산소 대조군보다 증가하였다. eNOS와 nNOS 발현은 정상 대조군 보다 저산소 대조군에서 감소하였고, eNOS의 발현은 $TGF-{\beta}1$ 투여군에서 증가하였지만 nNOS의 발현은 증가하지 않아 통계적 유의성이 없었다. eNOS mRNA와 nNOS mRNA의 발현은 iNOS와 반대로 $TGF-{\beta}1$ 투여군에서 저산소 대조군보다 감소하였다. NMDA 수용체 아단위 mRNA의 발현은 정상 대조군과 Sham 수술군에 비해 저산소 대조군에서 모두 감소하였으나 $TGF-{\beta}1$ 투여군에서 NR2C를 제외한 나머지 아단위의 발현은 저산소 대조군보다 증가하였다. 결 론 : 신생백서의 저산소 허혈 뇌손상에서 $TGF-{\beta}1$ 치료군에서 저산소로 인하여 감소된 NMDA 수용체 아단위의 발현을 증가시켜 흥분독성 기전과 관련성을 보이며, 증가된 iNOS 발현을 감소시키고 감소된 eNOS 발현을 증가시키는 질소 산화물 중재를 통한 뇌 보호 작용에 연관이 있을 것으로 생각된다.

Expression of Luteinizing Hormone (LH) Subunit Genes in Mouse Testis

  • Kim, Hee Soo;Lee, Sung-Ho
    • 한국발생생물학회지:발생과생식
    • /
    • 제21권3호
    • /
    • pp.327-333
    • /
    • 2017
  • Gonadotropins are heterodimers consisting an alpha chain ($Cg{\alpha}$) and a beta chain. Interestingly, presence of complicated $LH-{\beta}$ transcripts in rat testis was accidently found; testicular $LH-{\beta}$ transcripts were confined in seminiferous tubules to spermatids, and the translated products were localized in the elongated spermatids. We hypothesized that mouse testis has potential to produce the tissue specific $LH-{\beta}$ with similar structure to the rat testicular forms. To verify our hypothesis, we examined the adult mouse (ICR) testis using RT-PCR and immunohistochemistry. The PCR revealed the presence of the identical products in the reactions for three LH subunit types. The expected product sizes for mouse $Cg{\alpha}$ and $LH-{\beta}$ known as pituitary type were 224 bp and 503 bp, respectively. The testicular type $LH-{\beta}$ products were produced by a primer set based on the rat sequences, with unexpected size of 800 bp. Sequencing revealed that the proximal and distal parts (2-82 and 661- 773 bp, respectively) were homologous to rat testicular $LH-{\beta}$ cDNA, and middle part (83-660 bp) was a unique mouse-specific region. Both $Cg{\alpha}$ and $LH-{\beta}$ positive signals were in the round and elongated spermatids and mature sperms, and the $LH-{\beta}$ signals were more intense. In conclusion, our study demonstrated that the presence and localization of the LH subunits in mouse testis. Further studies will be needed to understand the precise structure and function of mouse testicular LH.

The Interaction between Methanol Dehydrogenase and MxaJ Protein of a Marine Methylotrophic Bacterium Methylophaga aminisulfidivorans $MP^T$

  • Kim, Hee-Gon
    • 한국미생물학회:학술대회논문집
    • /
    • 한국미생물학회 2008년도 International Meeting of the Microbiological Society of Korea
    • /
    • pp.163-163
    • /
    • 2008
  • Methylophaga aminisulfidivorans $MP^T$, a restricted facultative marine methylotrophic bacterium, was able to utilize methanol as a sole carbon and energy source, and possessed a methanol dehydrogenase (MDH) that is a key enzyme in the process of methanol oxidation. During purification of MDH, three types of MDH (MDH I, II, and III) were obtained in the cell free extracts from $MP^T$ cells grown on methanol. When analyzed by SDS-PAGE and ESI-FT ICR MS, MDH I was confirmed to consist of two subunits and with molecular masses of ~66 and ~10 kDa, respectively, in a form of ${\alpha}_2{\beta}_2$. While MDH II and MDH III contained an additional ~30 kDa protein, designated ${\gamma}$, in a form of ${\alpha}_2{\beta}_2{\gamma}$ and ${\alpha}_2{\beta}_2{\gamma}_2$, respectively. MDH III showed 1.5.2.0 times higher activity than MDH II, while MDH I remained the lowest activity. Based on these observations and experimental data, it seems that the original MDH conformation is ${\alpha}_2{\beta}_2{\gamma}2$ within $MP^T$ growing on methanol, and subunit ${\gamma}$ keeps MDH in an active form, and/or makes MDH easily bind to the substrate, methanol.

  • PDF

Type II and III Taste Bud Cells Preferentially Expressed Kainate Glutamate Receptors in Rats

  • Lee, Sang-Bok;Lee, Cil-Han;Kim, Se-Nyun;Chung, Ki-Myung;Cho, Young-Kyung;Kim, Kyung-Nyun
    • The Korean Journal of Physiology and Pharmacology
    • /
    • 제13권6호
    • /
    • pp.455-460
    • /
    • 2009
  • Glutamate-induced cobalt uptake reveals that non-NMDA glutamate receptors (GluRs) are present in rat taste bud cells. Previous studies involving glutamate induced cobalt staining suggest this uptake mainly occurs via kainate type GluRs. It is not known which of the 4 types of taste bud cells express subunits of kainate GluR. Circumvallate and foliate papillae of Sprague-Dawley rats (45~60 days old) were used to search for the mRNAs of subunits of non-NMDA GluRs using RT-PCR with specific primers for GluR1-7, KA1 and KA2. We also performed RT-PCR for GluR5, KA1, $PLC\beta2$, and NCAM/SNAP 25 in isolated single cells from taste buds. Taste epithelium, including circumvallate or foliate papilla, express mRNAs of GluR5 and KA1. However, non-taste tongue epithelium expresses no subunits of non-NMDA GluRs. Isolated single cell RT-PCR reveals that the mRNAs of GluR5 and KA1 are preferentially expressed in Type II and Type III cells over Type I cells.

Peptides derived from high voltage-gated calcium channel β subunit reduce blood pressure in rats

  • Hyung Kyu Kim;Jiyeon Jun;Tae Wan Kim;Dong-ho Youn
    • The Korean Journal of Physiology and Pharmacology
    • /
    • 제27권5호
    • /
    • pp.481-491
    • /
    • 2023
  • The β subunits of high voltage-gated calcium channels (HGCCs) are essential for optimal channel functions such as channel gating, activation-inactivation kinetics, and trafficking to the membrane. In this study, we report for the first time the potent blood pressure-reducing effects of peptide fragments derived from the β subunits in anesthetized and non-anesthetized rats. Intravenous administration of 16-mer peptide fragments derived from the interacting regions of the β1 [cacb1(344-359)], β2 [cacb2(392-407)], β3 [cacb3(292-307)], and β4 [cacb4(333-348)] subunits with the main α-subunit of HGCC decreased arterial blood pressure in a dose-dependent manner for 5-8 min in anesthetized rats. In contrast, the peptides had no effect on the peak amplitudes of voltage-activated Ca2+ current upon their intracellular application into the acutely isolated trigeminal ganglion neurons. Further, a single mutated peptide of cacb1(344-359)-cacb1(344-359)K357R-showed consistent and potent effects and was crippled by a two-amino acid-truncation at the N-terminal or C-terminal end. By conjugating palmitic acid with the second amino acid (lysine) of cacb1(344-359)K357R (named K2-palm), we extended the blood pressure reduction to several hours without losing potency. This prolonged effect on the arterial blood pressure was also observed in non-anesthetized rats. On the other hand, the intrathecal administration of acetylated and amidated cacb1(344-359)K357R peptide did not change acute nociceptive responses induced by the intradermal formalin injection in the plantar surface of rat hindpaw. Overall, these findings will be useful for developing antihypertensives.

Association of Two Polymorphisms of DNA Polymerase Beta in Exon-9 and Exon-11 with Ovarian Carcinoma in India

  • Khanra, Kalyani;Panda, Kakali;Bhattacharya, Chandan;Mitra, A.K.;Sarkar, Ranu;Bhattacharyya, Nandan
    • Asian Pacific Journal of Cancer Prevention
    • /
    • 제13권4호
    • /
    • pp.1321-1324
    • /
    • 2012
  • Background: DNA polymerase beta ($pol{\beta}$) is a key enzyme in the base excision repair pathway. It is 39kDa protein, with two subunits, one large subunit of 31 kDa having catalytic activity between exon V to exon XIV, and an 8 kDa smaller subunit having single strand DNA binding activity. Exons V to VII have double strand DNA binding activity, whereas exons VIII to XI account for the nucleotidyl transferase activity and exons XII to XIV the dNTP selection activity. Aim: To examine the association between $pol{\beta}$ polymorphisms and the risk of ovarian cancer, the present case control study was performed using 152 cancer samples and non-metastatic normal samples from the same patients. In this study, mutational analysis of $pol{\beta}$ genomic DNA was undertaken using primers from exons IX to XIV - the portion having catalytic activity. Results: We detected alteration in DNA polymerase beta by SSCP. Two specific heterozygous point mutations of $pol{\beta}$ were identified in Exon 9:486, A->C (polymorphism 1; 11.18%) and in Exon 11:676, A->C (polymorphism 2; 9.86%). The correlation study involving polymorphism 1 and 4 types of tissue showed a significant correlation between mucinous type with a Pearson correlation value of 4.03 (p=0.04). The association among polymorphism 2 with serous type and stage IV together have shown Pearson ${\chi}^2$ value of 3.28 with likelihood ratio of 4.4 (p=0.07) with OR =2.08 (0.3-14.55). This indicates that there is a tendency of correlation among polymorphism 2, serous type and stage IV, indicating a risk factor for ovarian cancer. Conclusion: Hence, the results indicate that there is a tendency for $pol{\beta}$ polymorphisms being a risk factor for ovarian carcinogenesis in India.

황연해독탕(黃連解毒湯)이 자발적(自發的) 고혈압(高血壓) 백서(白鼠)의 혈압(血壓) 신장(腎臟) 기능(機能)에 미치는 영향(影響) (Effect of Hwangryunhaedok-tang on Blood Pressure and Renal Functions in Spontaneously Hypertensive Rats)

  • 국윤범
    • 대한한의학방제학회지
    • /
    • 제10권1호
    • /
    • pp.113-129
    • /
    • 2002
  • The present study designed to investigate whether hwangryunhaedok-tang show an anti-hypertensive effect and elucidate its possible mechanism in spontaneously hypertensive rats. The systolic blood pressures (SBP) were significantly decreased as an oral administration of hwangryunhaedok-tang compared with their control group. The urine volume was significantly increased by administration of hwangryunhaedok-tang but urinary sodium (UNaV), potassium (UKV), chloride excretion (UCIV) were not remarkably affected. The urinary creatinine excretion rate (UcrV) was significantly increased in rats administered with hwangryunhaedok-tang in association with increase of creatinine clearance (Ccr). The urine osmolality (Uosmol) was significantly decreased in SHR administered with hwangryunhaedok-tang without being changed in solute-free water reabsorption ( TcH20). The expressions of Aquaporin 2 (AQP-2). 3 and ${\alpha}\;1$, ${\beta}\;1$ subunits of Na.K-ATPase were determined by Western blot analysis to assess the role of these proteins in association with changes of renal functions in SHR administered with hwangryunhaedok-tang. The expression of AQP-2 and 3 protein was significantly down-regulated in the kidney of SHR administered with hwangryunhaedok-tang compared with those in control rats without being altered expression of ${\alpha}\;1$, ${\beta}\;1$ subunits of Na,K-ATPase. In the in vitro assay, Angiotensin converting enzyme (ACE) was inhibited by hwangryunhaedok-tang in a dose-dependent manner. Berberine and/or palmatine, which are well known as a main components of hwangryunhaedok-tang, also have an ACE inhibitory effects in a dose-dependent manner. Taken together, these results suggest that hwangryunhaedok-tang lowered blood pressure through the increase of diuresis caused by down-regulation of water channels and the inhibition of Angiotensin converting enzyme.

  • PDF

콩 돌연변이 계통의 단백질 특성 (Seed Protein Quality of Soybean Mutants)

  • 양무희
    • 한국작물학회지
    • /
    • 제39권3호
    • /
    • pp.278-284
    • /
    • 1994
  • 콩단백질의 황 아미노산함량은 가축 영양학상 중요한 위치를 차지하기 때문에 신계통이 가져야만 할 필수조건일지도 모른다. 콩 계통간에 저장단백질의 유전적변이가 존재한다면 이는 기존의 육종방법을 통하여 콩의 종자단백질 구성성분을 유전적으로 변경하여 품질을 개량할 수 있는 가능성을 시사하고 있다. 본 연구는 여러 문헌에 보고된 콩종자 저장단백질의 돌연변이 계통들을 선별하여 콩단백질의 품질을 향상시키기 위한 육종 재료로서의 가능성을 평가하기 위하여 실행되었다. 수집된 돌연변이 계통들은 저장단백질의 또 다른 특성을 나타내었다. 그 돌연변이 계통들 중에서 Keburi(P.I.417016), Keburi(P.I.506817), P.I.154608-1 등은 황 아미노산 함량이 상대적으로 다른 돌연변이 계통보다 높은 1.9, 2.1, 1.8%를 나타내었으며, 이는 7S 단백질인 ${\alpha}$ ', ${\alpha}$ , ${\beta}$단백질 함량이 상대적으로 낮기 때문인 것으로 나타났다. 그러므로 그 돌연변이 계통들 중에서 Keburi(P.I.417016), Keburi(P.I.506817), P.I.54608-1 등은 황 아미노산 함량을 향상시키기 위한 중요한 육종재료로, 그 외 돌연변이 계통들은 다른 용도의 육종 재료로 이용할 수 있을 것으로 추측된다.

  • PDF

Function of the Tethered rec-eCG in Rat and Equine Receptors

  • Park, Jong-Ju;Jargal, Naidansuren;Yoon, Jong-Taek;Min, Kwan-Sik
    • Reproductive and Developmental Biology
    • /
    • 제33권4호
    • /
    • pp.229-236
    • /
    • 2009
  • The glycoprotein hormone family represents a class of heterodimers, that includes the placental hormone equine chorionic gonadotropin (eCG) and the anterior pituitary hormones- follitropin (FSH), lutropin (LH), and thyrotropin (TSH). The 4 hormones are heterodimers, with a common $\alpha$-subunit and unique $\beta$-subunits. eCG is the most heavily glycosylated of the known pituitary and placental glycoprotein hormones. Recent observations using single chain glycoprotein hormone analogs in which, the $\beta$-and $\alpha$-subunits are linked, implied that heterodimeric-like quaternary configuration is not a prerequisite for receptor/signal transduction. To study the function and signal transduction of tethered rec-eCG, a single chain eCG molecule was constructed and rec-eCG protein was produced. Molecular mass of the single chain is about 45 kDa. All mice were ovulated by tethered rec-eCG treatment. The dual activity of tethered rec-eCG was determined in receptor cell lines of nonequid species; in fact, this dual activity was proven in species other than horse. Tethered rec-eCG in equids does not bind to FSH receptors, suggesting that eCG is primarily an LH-like hormone in the horse. Taken together, these data suggest that tethered rec-eCG has dual activity in nonequid species in vitro. However, it has only LH-like activity in equid species in vitro.