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1.
The mean basal specific activities and the mean % deficiencies of the activity of the glutamic oxaloacetic transaminase of the erythrocytes were identical (n.s.) for a group of eight patients with a severe carpal tunnel syndrome and for a group of eight university students. There was no significant difference in the increases in the specific activities for the patients and the students at 4 concentrations of pyridoxal 5′-phosphate. The apparent Km for the patients and the students was 95 μM and 61 μM (n.s.) respectively. It is concluded from these data in conjunction with previous findings that the carpal tunnel syndrome is a deficiency disease of vitamin B6, which is probably primary rather than one of a dependency state.  相似文献   
2.
A new approach to the study of the molecular arrangements of proteins in membranes is described. Irradiation with visible light of native erythrocytes or washed erythrocyte membranes suspended in buffers containing a) riboflavin, fluorescein or fluorescein coupled to dextran and b) 3H-labelled tryptophan resulted in incorporation of radioactivity into the membrane proteins. Polyacrylamide gel electrophoresis of solubilized membranes followed by radioactivity measurements of the separated membrane proteins revealed that in native erythrocytes the protein components known to be located at the exterior cell surface, Band 3 and the major sialoglycoproteins became specifically labelled, whereas in washed lysed cells all of the major membrane proteins were labelled.  相似文献   
3.
A novel synthetic foot-and-mouth disease virus (FMDV) peptide vaccine consisting of a synthetic B-cell and macrophage activator covalently linked to an amphiphilic alpha-helical T-cell epitope was developed. The low molecular weight vaccine of 3400 daltons is composed of virus VP1 antigenic determinant and the immunologically active lipotripeptide tripalmitoyl-S-glyceryl-cysteinyl-seryl-serine (P3CSS) as built-in adjuvant. The vaccine, tripalmitoyl-S-glyceryl-cysteinyl-seryl-seryl-FMDV-VP1 (VP1 = serotype O1K 135-154) induces protection against homologous challenge and serotype-specific virus neutralizing antibodies in guinea pigs after single administration without further adjuvants or carriers. A P3CSS conjugate with the FMDV-VP1 segment 135-154 of strain O Wuppertal produced only poor cross-protection against challenge with O1K virus. The antigenic determinant VP1(135-154) is an amphiphilic alpha-helix, as shown by CD. Molecular dynamics simulations (MDS) carried out using the highly homologous alpha-helical alcohol dehydrogenase (ADH) segment H3 as starting conformation for VP1(138-149) suggest that the FMDV segment 138-149 may adopt alpha-helical conformation during binding to its T-cell receptor, and that the development of the system during MDS may be considered as the dissociation step of the complex.  相似文献   
4.
The preferred solution conformation of the PRP-hexapeptide (Tyr-Val-Pro-Leu-Phe-Pro) and of some of its structural analogues was investigated by NMR-spectroscopy, spectrofluorimetry and computer simulation technic. It was found that the preferred conformation is characterized by cis'-conformation of Pro3 and the gamma-turn on the Leu4-residue: for Val2 and Phe5 a beta-structure seems to be privileged. In such a conformation Val2 and Leu4 residues occupy exactly the same positions in space as residues i and i + 3 in an alpha-helix. It suggests that the PRP-hexapeptide can interact with receptor protein inducing or stabilizing its helical conformation by "knobs into holes" packing.  相似文献   
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D Misiti  H W Moore  K Folkers 《Biochemistry》1965,4(6):1156-1160
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7.
Summary The structure-activity data of 6 years on 395 analogs of the luteinizing hormone releasing hormone (LHRH) have been studied to determine effective substituents for the ten positions for maximal antiovulatory activity and minimal histamine release. The numbers of substituents studied in the ten positions are as follows: (41)1-(12)2-(12)3-(5)4-(47)5-(52)6-(16)7-(18)8-(4)9-(8)10. In position 1, DNal and DQal were effective with the former being more frequently the better substituent. DpClPhe was uniquely effective in position 2. Positions 3 and 4 are very sensitive to change. D3Pal in position 3 and Ser in position 4 of LHRH were in the best antagonists. PicLys and cPzACAla were the most successful residues in position 5 with cPzACAla being the better substituent. Position 6 was the most flexible and many substituents were effective; particularly DPicLys. Leu7 was most often present in the best antagonists. In position 8, Arg was effective for both antiovulatory activity and histamine release; ILys was effective for potency and lesser histamine release. Pro9 of LHRH was retained. DAlaNH2 10 was in the best antagonists.Abbreviations AABLys N -(4-acetylaminobenzoyl)lysine - AALys N -anisinoyl-lysine - AAPhe 3-(4-acetylaminophenyl)lysine - Abu 2-aminobutyric acid - ACLys N -(6-aminocaproyl)lysine - ACyh 1-aminocyclohexanecarboxylic acid - ACyp 1-aminocyclopentanecarboxylic acid - Aile alloisoleucine - AnGlu 4-(4-methoxy-phenylcarbamoyl)-2-aminobutyric acid - 2ANic 2-aminonicotinic acid - 6ANic 6-aminonicotinic acid - APic 6-aminopicolinic acid - APh 4-aminobenzoic acid - APhe 4-aminophynylalanine - APz 3-amino-2-pyrazinecarboxylic acid - Aze azetidine-2-carboxylic acid - Bim 5-benzimidazolecarboxylic acid - BzLys N -benzoyllysine - Cit citrulline - Cl2Phe 3-(3,4-dichlorphenyl)alanine - cPzACAla cis-3-(4-pyrazinylcarbonylaminocyclohexyl)alnine - cPmACAla cis-3-[4-(4-pyrimidylcarbonyl)aminocyclohexyl]alanine - Dbf 3-(2-dibenzofuranyl)alanine - DMGLys N -(N,N-dimethylglycyl)lysine - Dpo N -(4,6-dimethyl-2-pyrimidyl)-ornithine - F2Ala 3,3-difluoroalanine - hNal 4-(2-naphthyl)-2-aminobutyric acid - HOBLys N -(4-hydroxybenzoyl)lysine - hpClPhe 4-(4-chlorophenyl)-2-amino-butyric acid - Hse homoserine, 2-amino-4-hydroxybutanoic acid - ICapLys N -(6-isopropylaminocaproyl)lysine - ILys N -isopropyllysine - Ind indoline-2-carboxylic acid - INicLys N -isonicotinoyllysine - IOrn N -isopropylornithine - Me3Arg NG,NG,NG-trimethylarginine - Me2Lys N ,N -dimethyllysine - MNal 3-[(6-methyl)-2-naphtyl]alanine - MNicLys N -(6-methylpicolinoyl)lysine - MPicLys N -(6-methylpicolinoyl)lysine - MOB 4-methoxybenzoyl - MpClPhe N-methyl-3-(4-chlorphenyl)lysine - MPZGlu glutamic acid,-4-methylpiperazine - Nal 3-(2-naphthyl)alanine - Nap 2-naphthoic acid - NicLys N -nicotinoyllysine - NO2B 4-nitrobenzoyl - NO2Phe 3-(4-nitrophenyl)alanine - oClPhe 3-(2-chlorphenyl)alanine - Opt O-phenyl-tyrosine - Pal 3-(3-pyridyl)alanine - 2Pal 3-(2-pyridyl)alanine - 2PALys N -(3-pyridylacetyl)lysine - pCapLys N -(6-picolinoylaminocaproyl)lysine - pClPhe 3-(4-chlorophenyl)alanine - pFPhe 3-(4-fluorophenyl)-alanine - Pic picolinic acid - PicLys N -picolinoyllysine - Pip piperidine-2-car-boxylic acid - PmcLys N -(4-pyrimidylcarbonyl)lysine - Ptf 3-(4-trifluromethyl phenyl)alanine - Pz pyrazinecarboxylic acid - PzAla 3-pyrazinylalanine - PzAPhe 3-(4-pyrazinylcarbonylaminophenyl)alanine - Qal 3-(3-quinolyl)alanine - Qnd-Lys N -quinaldoyllysine - Qui 3-quinolinecarboxylic acid - Qux 2-quinoxalinecarboxylic acid - Tic 1,2,3,4-tetrahydroisoquinoline-3-carboxylic acid - TinGly 2-thienylglycine - tNACAla trans-3-(4-nicotinoylaminocyclohexyl)-alanine - tPACAla trans-3-(4-picolinoylaminocyclohexyl)alanine  相似文献   
8.
A precondition for the chemotherapeutic treatment of a variety of virally-induced human diseases and malignant conditions is a highly selective interaction of the drug molecule to be used with it's biological target. To ensure the development of novel, effective drugs, it is essential that the biological target is well characterised with regard to it's structure and activity. Such characterisation relies upon adequate amounts of pure target being available. One of the most important enzymatic importers for antimetabolites is the enzyme thymidine kinase. In this article an in vitro protein expression system is described which facilitates the production of milligram amounts of pure and biologically active thymidine kinase, from a number of important biological sources. Results have shown that the in vitro produced enzyme has the exact biochemical propeties of the in vivo enzyme. Thus the in vitro protein expression system is an ideal vechicle to facilitate an in depth investigation of the enzyme's biological properties.  相似文献   
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