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1.
用四氮唑蓝光化学还原法对所合成的KCu(IDA)(Ser)·2H2O、KCu(IDA)(Ala)·H2O、Cu(IDA)(en)、KCu(IDA)(Gly)·H2O和Cu(IDA)·2H2O(IDA=N(羧基甲基)-甘氨酸,Ser=丝氨酸,Ala=丙氨酸,en=乙二胺,Gly=甘氨酸)等5种氨基酸─铜(Ⅱ)配合物进行了活性测定,发现它们均具有天然超氧化物歧化酶活性,其活性依次为0.34、0.45、0.50、0.54、0.72Cuμmol·L-1。 相似文献
2.
5—羟色胺对肺动脉平滑肌细胞在缺氧条件下增殖的作用 总被引:2,自引:1,他引:1
本研究应用细胞培养、^3H-TdR掺入,核酸分子杂交、免疫组织化学染色技术,探讨无氧(0%O2+95%N2+5%CO2)和/或低氧(2.5 ̄3%O2+92%N2+5%CO2)对新生小牛肺动脉平滑肌细胞增殖和5-羟色胺转载体基因表达的影响。结果表明:无氧24h可刺激PASM的DNA合成,^3H-TdR的掺入增加(P〈0.05),加入5-羟色胺能非常显著地促进无氧PASM增殖(P〈0.001),而对常 相似文献
3.
蝴蝶兰根段的组织培养 总被引:36,自引:2,他引:36
1 植物名称 蝴蝶兰(PhalaenopsisMellerGold“NFS”)。2 材料类别 根段。3 培养条件 (1)愈伤组织的诱导及分化培养基:B5+NAA1.5mg·L-1(单位下同)+KT0.2+CM150ml·L-1+3%蔗糖;(2)原球茎增殖培养基:B5+GA0.05+CH120+3%蔗糖;(3)小苗生长培养基:1/2MS+20%香蕉泥+2%蔗糖;(4)诱导生根培养基:1/2MS+IBA0.3+2%蔗糖。上述培养基均加0.2%活性炭,0.58%琼脂粉,pH为5.5;培养基在121℃高… 相似文献
4.
条斑紫菜中R-藻红蛋白的生化特性 总被引:5,自引:0,他引:5
条斑紫菜的R-藻红蛋白(R-PE),在CM-52柱上用含8mol/L脲的0.02mol/L乙酸铵缓冲液(pH=5.05)洗脱,观察到3条色带,经吸收光谱测定表明,它们分别是α、β、γ亚基。用SDS-PAGE测定的α、β和γ亚基分子量分别是17.0kd,18.0kd和31.7kd。R-PE中亚基的摩尔比是6α:6β:1γ。条斑紫菜的R-PE最稳定的聚集态分子量是229kd。各亚基的发色团含量:α亚基含2个藻红胆素(PEB),β亚基含1个PEB和0.5个藻尿胆素(PUB),γ亚基含2个PEB和3个PUB。结合R-PE和各亚基的氨基酸组成分析,条斑紫菜的R-PE亚基组成是(αβ)6γ。 相似文献
5.
人巨细胞病毒的分子克隆及其特异性DNA探针的制备 总被引:6,自引:0,他引:6
从人巨细胞病毒(HCMV)培养物中提取HCMV并抽提其DNA,经限制性内切酶BamHI完全消化后,与质粒pBluescript-SK重组建立了HCMV的DNA文库,从此文库。中随机筛选出两个重组质粒(pCMV-1和pCMV-2),用BamHI分析证明其中所含的病毒DNA片段的大小分别为1.0kb和7.5kb,将这两种质粒大量扩增纯化后,用光生物素进行标记作为探针,证明其只与HCMV反应,与正常人细胞DNA及Ⅰ型和Ⅱ型单纯疤疹病毒DNA无交叉反应。 相似文献
6.
黑曲霉生产β-葡萄糖苷酶发酵条件的研究产 总被引:1,自引:0,他引:1
经多项式回归分析,研究了不同浓度N 源、C 源、无机盐等对酶产量的影响,确定出最佳培养基配方为:麸皮4 .9 % ,(NH4)2SO4 0 .4 % ,KH2PO4 0 .29 % ,CaCl2 0 .05 % ,MgSO4·7H2O0 .04 % ,FeSO4·7H2 O5mg·L- 1 ,ZnCl2 1 .4mg·L- 1 ,0 .2 % 油酸钠.并对培养温度、时间、培养基初始pH、通气量、接种量、接种方式等培养条件进行优化,使黑曲霉生产β葡萄糖苷酶的产量由17U·ml- 1 增至21 .3U·ml- 1 . 相似文献
7.
地鼠肾细胞狂犬病疫苗原液经100 kD 膜浓缩 30 倍,分别选用(1)DEAE Sepharose CL-6B离子交换层析法;(2)Sephacry1 S-200 HR 分子筛选层析法;(3)二次蔗糖等密度区带离心法对其进行纯化。用此三种方法各试制3 批精制疫苗,结果表明,经DEAE Sepharose CL-6B离子交换层析纯化后疫苗总蛋白含量减少99% 以上,抗原比活性提高159 倍,抗原回收率达50% ,纯化疫苗以NIH 法效力测定平均为5.4 IU/2m l;经Sephacry1 S-200HR 分子筛层析纯化后疫苗总蛋白含量减少 98% 以上,抗原比活性提高41 倍,抗原回收率达63% ,纯化疫苗效力平均为6.25 IU/2m l;经一次蔗糖等密度区带离心法纯化后疫苗总蛋白含量减少98% 以上,抗原比活性提高321 倍,抗原回收率达43% ,纯化疫苗效力平均为6.18 IU/2m l,三种纯化疫苗均符合W HO 规程要求。 相似文献
8.
沙葱的组织培养和植株再生 总被引:7,自引:0,他引:7
1植物名称沙葱(Alliummongolicum),又名蒙古韭。种子来源于中国科学院沙漠研究所宁夏沙坡头沙漠试验站。2材料类别幼苗的叶片。3培养条件(1)愈伤组织诱导培养基:MS+2,4-D2.0mg·L-1(单位下同)+KT0.2+CH(水解酪蛋白)500+蔗糖3%;(2)分化培养基同(1),但2,4-D为0.5;(3)生根培养基:1/2MS+1BA1.0+蔗糖3%。上述培养基均加0.7%琼脂粉固化,pH调至5.8~6.2。培养温度(25±2)℃。愈伤组织诱导阶段为暗培养,分化阶段每日光照12… 相似文献
9.
猪精子凝集素的纯化,性质及其作用 总被引:3,自引:1,他引:2
用胎球蛋白-Sepharose亲和层析和凝胶过滤层析从精子和精浆中分离纯化了猪精子凝集素(简称BSL)。BSL的血凝活性只被若干糖蛋白和聚糖所抑制。BSL的分子量为56kd,由分子量分别为13.6kd(β)和16.0kd(α)的两个不同的亚基以α1β3所组成。BSL为糖蛋白,含中性糖3.2%,不含唾液酸。用ELISA法测定猪精子中BSL的含量及分布,表明70%嵌入在精子膜中,25%结合在精子表面, 相似文献
10.
曾祥群 《氨基酸和生物资源》1997,(1)
异亮氨酸质量标准①—译自《BP93版》曾祥群江西鹰潭市生物化学制品厂C6H13NO2:131.273-32-5[定义]异亮氨酸是(2S,3S)-2-氨基-3-甲基戊酸,以干燥品计,其含C6H13NO2不得少于98.5%,不得高于101.0%。[特征]... 相似文献
11.
In addition to the alpha and beta chains of the MHC class II restricted antigen receptor, monoclonal anti-receptor antibodies coprecipitate four polypeptides that appear to be noncovalently associated with the alpha-beta dimer of murine T cells. Included in the murine T cell antigen receptor complex are two glycoproteins of 25 kd (gamma) and 21 kd (delta) and two nonglycosylated polypeptides of 26 kd (epsilon) and 16 kd (zeta). The epsilon chain appears to possess an intrachain disulfide bond and zeta exists in the complex as a disulfide-linked homodimer. The delta chain is phosphorylated on a serine residue in response to T cell activation with antigen. In contrast, both delta and epsilon are phosphorylated in response to treatment of the T cells with phorbol 12-myristate 13-acetate. These polypeptides may play a role in the transduction of the signal(s) in T cell activation. 相似文献
12.
Purification and characterisation of MHC class I antigen from rat liver with monoclonal antibody 总被引:1,自引:0,他引:1
T Fukumoto K Tamakoshi H Ohta A Yamashita K Maeda 《The International journal of biochemistry》1986,18(11):971-977
We have described three monoclonal antibodies (HAM1, HAM2, and HAM3) to rat liver cell membrane glycoproteins. Recently also we reported another monoclonal antibody (HAM4) to rat hepato-renal membrane antigen. Using these monoclonal antibodies, it is possible to purify membrane antigens. This paper describes the details of the purification and the nature of the antigen purified with one of the monoclonal antibodies (HAM2) to rat liver cell membrane glycoproteins. Antigen was purified with immunoaffinity column. The amino acid composition was determined and compared with those of mice MHC class I antigen (H-2) and with the rat lymphocyte membrane antigens which were purified with monoclonal antibodies and of which amino acids compositions were determined. 相似文献
13.
Evidence for specific association between class I major histocompatibility antigens and the CD8 molecules of human suppressor/cytotoxic cells 总被引:6,自引:0,他引:6
Human T lymphocytes, metabolically labeled with 35S-cysteine and 35S-methionine, were reacted with the homobifunctional cross-linking reagent, dithiobis (succinimidyl propionate) (DSP). When detergent lysates from these cells were immunoprecipitated with a monoclonal antibody reactive with the CD8 antigen, a radiolabeled protein of approximately 44 kd was coprecipitated with the CD8 molecule. Immunoprecipitates from detergent lysates prepared without prior chemical cross-linking contained only the 33 kd CD8 molecule. Similar results were obtained when T lymphocytes or a cytotoxic T cell clone (T4T8Cl) were radiolabeled with 32P-orthophosphoric acid. The 44 kd CD8-associated protein was identified as the heavy chain of the class I major histocompatibility antigen by depletion in preclearing experiments with anti-class I MHC antibody and by peptide mapping. Further analyses indicated that the CD8-class I MHC association is due, in part at least, to disulfide bonding, which may be susceptible to cleavage during processing of cell lysates. 相似文献
14.
To identify the cellular receptors and other cell surface molecules playing essential roles in the transmission of human T-cell leukemia virus type 1 (HTLV-1), we have been isolating monoclonal antibodies (mAbs) that are capable of inhibiting HTLV-1-induced syncytium formation. In the present study, we isolated two mAbs, H11 (IgM) and H14 (IgG1), inhibitory to syncytium formation in the coculture of TOM-1 or C91/PL (both HTLV-1-positive human T-cell lines) and MOLT-4/8 (HTLV-1-negative human T-cell line) by immunizing the membrane fraction of human osteosarcoma line HOS. By immunoprecipitation and immunoblotting, H11 and H14 were found to be specific for MHC class I heavy chain and beta 2-microglobulin (beta 2 M), respectively. Among the four commercially obtained mAbs, two mAbs for MHC class I antigen and two mAbs to beta 2 M, one mAb to MHC class I antigen and one mAb to beta 2 M were also found to be inhibitory to the syncytium formation. The functional comparison of these mAbs revealed that the syncytium-inhibitory mAbs induced strong homotypic cell adhesion particularly in the HTLV-1-positive T-cell lines. This cell adhesion was dependent on temperature, energy metabolism, and microfilament function but not on the activity of protein kinase C or divalent cations. These results suggest a novel type of LFA-1-independent cell adhesion induced by signal transduction via MHC class I antigen. 相似文献
15.
Eden PA Christianson GJ Fontaine P Wettstein PJ Perreault C Roopenian DC 《Journal of immunology (Baltimore, Md. : 1950)》1999,162(8):4502-4510
Of the many minor histocompatibility (H) Ags that have been detected in mice, the ability to induce graft vs host disease (GVHD) after bone marrow transplantation is restricted to a limited number of immunodominant Ags. One such murine Ag, B6dom1, is presented by the H2-Db MHC class I molecule. We present biochemical evidence that the natural B6dom1 peptide is indistinguishable from AAPDNRETF, and we show that this peptide can be isolated from a wide array of tissues, with highest levels from the lymphoid organs and lung. Moreover, we employ a novel, somatic cell selection technique involving CTL-mediated immunoselection coupled with classical genetics, to show that B6dom1 is encoded by the H7 minor H locus originally discovered approximately 40 years ago. These studies provide a molecular genetic framework for understanding B6dom1, and exemplify the fact that mouse minor H loci that encode immunodominant CTL epitopes can correspond to classical H loci originally identified by their ability to confer strong resistance to tumor transplantation. Additionally, these studies demonstrate the utility of somatic cell selection approaches toward resolving H Ag immunogenetics. 相似文献
16.
York IA Grant EP Dahl AM Rock KL 《Journal of immunology (Baltimore, Md. : 1950)》2005,174(11):6839-6846
COS7 (African Green Monkey kidney) cells stably transfected with the mouse MHC class I allele H-2K(b) were mutagenized, selected for low surface expression of endogenous MHC class I products, and subcloned. A mutant cell line, 4S8.12, expressing very low surface MHC class I (approximately 5% of parental levels) was identified. This cell line synthesized normal levels of the MHC class I H chain and beta(2)-microglobulin, as well as normal levels of TAP, tapasin, GRP78, calnexin, calreticulin, ERp57, and protein disulfide isomerase. Full-length OVA was processed to generate presented H-2K(b)-SIINFEKL complexes with equal efficiency in wild-type and mutant cells, demonstrating that proteasomes, as well as TAP and tapasin, functioned normally. Therefore, all the known components of the MHC class I Ag presentation pathway were intact. Nevertheless, primate (human and monkey) MHC class I H chain and beta(2)-microglobulin failed to associate to form the normal peptide-receptive complex. In contrast, mouse H chains associated with beta(2)-microglobulin normally and bound peptide at least as well as in wild-type cells. The 4S8.12 cells provide strong genetic evidence for a novel component in the MHC class I pathway. This as-yet unidentified gene is important in early assembly of primate, but not mouse, MHC class I complexes. 相似文献
17.
Purified H.8 (Lip) antigen was coupled to tresyl-activated Sepharose 4B and used in affinity columns to purify anti-Lip antibodies from convalescent patient sera and from immune rabbit sera. Affinity-purified anti-Lip antibodies isolated from two convalescent patient sera contained 1000 and 1280 ELISA units of antibody and included antibodies of IgG, IgA, and IgM isotypes. An anti-Lip mouse monoclonal ascites (2-1-CA2) had 28,400 ELISA units of antibody. Bactericidal assays were performed using three different case strains of Neisseria meningitidis group B, namely 44/76, 8532, and 8047. Neither preparation of purified human anti-Lip antibodies had detectable bactericidal activity against strains 44/76 and 8532, but one of the two had a titer of 1:4 against strain 8047. Anti-Lip antibodies that were purified from immune rabbit serum and contained 1600 ELISA units of anti-Lip antibodies also failed to show detectable bactericidal activity. The rabbits were immunized with purified Lip antigen and showed specific antibody levels of 2000-2200 units by ELISA, but even the unfractionated sera had little or no bactericidal activity against the test strains. The high titer mouse monoclonal ascites had no bactericidal activity against the test strains. The poor bactericidal activity associated with monoclonal and polyclonal antibodies to the Lip antigen suggest that in spite of other attractive properties it may not be useful as a meningococcal vaccine. 相似文献
18.
Clonal diversity, somatic mutation, and immune memory to phosphocholine-keyhole limpet hemocyanin 总被引:5,自引:0,他引:5
M P Stenzel-Poore M B Rittenberg 《Journal of immunology (Baltimore, Md. : 1950)》1989,143(12):4123-4133
Group II antibodies to phosphocholine (PC)-keyhole limpet hemocyanin in BALB/c mice are genetically diverse and of a defined binding phenotype which recognizes the hapten, phenyl-PC, and PC coupled to protein but not free PC. We sequenced the V regions of 14 kappa and lambda-bearing group II antibodies. Both types show extensive somatic mutations. The pattern of the mutations differs between kappa and lambda antibodies. The nature of the somatic mutation in lambda chains suggests strong Ag selection on the L chain but not the H chain of the lambda-bearing antibodies. The reverse pattern of selection was observed among kappa-containing antibodies wherein the accumulation of replacement mutations in the CDR of the H chain appears to result from selection while changes in the L chain appear unselected. From these findings it appears that somatic mutation plays a major role in anti-PC-keyhole limpet hemocyanin memory development because all 14 antibodies displayed changes from germ-line sequences. 相似文献
19.
The human T cell receptor: appearance in ontogeny and biochemical relationship of alpha and beta subunits on IL-2 dependent clones and T cell tumors 总被引:49,自引:0,他引:49
O Acuto R E Hussey K A Fitzgerald J P Protentis S C Meuer S F Schlossman E L Reinherz 《Cell》1983,34(3):717-726
The human T cell receptor for antigen (Ti) has recently been identified on IL-2 dependent T cell clones as a 90 kd disulfide-linked heterodimer comprised of one 49-51 kd alpha (alpha) and one 43 kd beta (beta) chain. These subunits are noncovalently associated with a monomorphic 20-25 kd T3 molecule. Here, we produce monoclonal antibodies to a human tumor (REX) derived from an earlier stage of thymic differentiation in order to determine whether clonotypic structures are expressed and to define the ontogeny of Ti. The results of SDS-PAGE and peptide map analyses indicate that an homologous T3-associated heterodimer is synthesized and expressed by REX. This glycoprotein shares several peptides in common with clonotypic structures on an IL-2 dependent T cell clone. In addition, similar Ti related molecules appear during intrathymic ontogeny in parallel with surface T3 expression. The latter findings provide the structural basis for the immunological competence observed exclusively within the T3+ thymocyte compartment. 相似文献
20.
HCV core protein immunization with Montanide/CpG elicits strong Th1/Th2 and long-lived CTL responses
Roohvand F Aghasadeghi MR Sadat SM Budkowska A Khabiri AR 《Biochemical and biophysical research communications》2007,354(3):641-649
An efficient vaccine against Hepatitis C virus (HCV) infection requires induction of strong humoral and cellular responses against viral proteins. We evaluated the immunogenicity of HCV core protein (HCVcp), a prime vaccine candidate, formulated in various human compatible adjuvants. An Escherichia coli-expressed HCVcp, purified in native conditions was used for murine immunization in separate groups of: free HCVcp (Ag), Ag+C/IFA (Freunds), Ag+CpG, Ag+M720 (Montanide ISA 720), Ag+F127 (Pluronic acid) and cocktails of Ag+F127+CpG and Ag+M720+CpG. Mice immunized with M720(+CpG) developed the highest HCVcp-specific titers of total IgG, IgG1, 2a, 2b, and that of IFN-gamma and IL-4 cytokines compared to all other groups. HCVcp-specific-CTLs against relevant MHC class I peptides were detected only for Ag+M720+CpG, Ag+M720, and Ag+CpG groups and could be blocked by antimouse-CD8 antibodies. While CTLs were stable, only F127 formulated groups demonstrated detectable IgG antibodies one year post-immunization. Hence, HCVcp formulated in M720 (with a synergistic effect by inclusion of CpG) could induce balanced and strong Th1/Th2 responses with long-lived CD4(-)CD8(+) CTLs. 相似文献