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PROTEOLYSIS Of SKELETAL-MUSCLE ADENYLATE-CYCLASE - DESTRUCTION AND RECONSTITUTION Of fLUORIDE AND GUANYLNUCLEOTIDE SENSITIVITY

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BIOCHIMICA ET BIOPHYSICA ACTA 1980年第3期631卷 393-401页

作者： DRUMMOND, GI NAMBI, P UNIV CALGARY DEPT CHEM BIOCHEM UNIT CALGARY T2N 1N4 ALBERTA CANADA

Adenylate cyclase was measured in skeletal muscle plasma membranes incubated with subtilisin. Under specific conditions the protease preferentially inactivated fluoride and guanylnucleotide sensitivity. following protease treatment, membranes were solubilized with Lubrol 12A9 and subjected to ion-exchange chromatography. Adenylate cyclase was eluted with 200 mM NaCl;the enzyme recovered was unresponsive to Naf or guanylyl imidodiphosphate. Responsiveness to the 2 ligands was restored by adding a heart fraction in which basal activity had been destroyed by heating at ***. C or by adding a soluble skeletal muscle fraction in which basal activity had been destroyed by N-ethylmaleimide. The solubilized subtilisin-treated skeletal muscle preparation may serve as a source of catalytic activity for the study and purification of regulatory factors for adenylate cyclase.

关键词： Adenylate cyclase f − sensitivity Proteolysis Guanylnucleotide (Skeletal muscle) Gpp(NH)p guanyl-5′-yl imidodiphosphate

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PLANT INHIBITORS Of SERINE PROTEINASES - HAGEMAN-fACTOR fRAGMENT, KALLIKREINS, PLASMIN, THROMBIN, fACTOR-XA, TRYPSIN, AND CHYMOTRYPSIN

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THROMBOSIS RESEARCH 1980年第2期20卷 163-171页

作者： HOJIMA, Y PIERCE, JV PISANO, JJ Section on Physiological Chemistry Laboratory of Chemistry National Heart Lung and Blood Institute Bethesda Maryland 20205 U.S.A.

Numerous plants were tested for ihibitors of human Hageman factor fragment (Hff), plasma kallikrein, urinary kallikrein, plasmin, thrombin, porcine pancreatic kallikrein and bovine factor Xa, trypsin, and chymotrypsin. Pumpkin seeds and iris bulbs contain trypsin inhibitors which specifically inhibit Hff. flower *** those of tulip, lily, hyacinth, and *** unrecognized rich sources of inhibitors with different inhibitory spectrums and physicochemical properties.

关键词： Hageman factor fragment inhibitor kallikrein inhibitor trypsin inhibitor Hf f Hageman factor fragment TAME N α -tosyl-L-arginine methyl ester BTEE N-benzoyl-L-tyrosine ethyl ester IU inhibitor unit M r molecular weight

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CHLOROPLAST BIOGENESIS .29. THE OCCURRENCE Of SEVERAL NOVEL CHLOROPHYLL-A AND CHLOROPHYLL-B CHROMOPHORES IN HIGHER-PLANTS

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BIOCHIMICA ET BIOPHYSICA ACTA 1980年第2期590卷 234-247页

作者： REBEIZ, CA BELANGER, fC fREYSSINET, G SAAB, DG UNIV ILLINOIS DEPT HORT PLANT PIGMENTS BIOCHEM & PHOTOBIOL LAB URBANA IL 61801 USA

With the use of low temperature spectrofluorometry and matrix calculations it was demonstrated that the chlorophyll [Chl] a pool of higher plants [Cucumis sativus and Spinacia oleracea] was made up of 4 different chl a chromophores. The latter were segregated by high pressure liquid chromatography on a silica column. They were designated Chl a (E432 f664), Chl a (E436 f670), Chl a (E443 f672) and Chl a (E446 f674), where E refers to the Soret excitation maximum and f to the fluorescence emission maximum at ***. K in ether. The Chl b pool consisted of at least 4 different Chl b chromophores which were designated: Chl b (E465), Chl b (E470), Chl b (E475) and Chl b (E485). The various chlorophyll chromophores apparently differed by the degree of oxidation of their side chains at the 2 and 4 positions of the macrocycle. The chemical modifications at the 2 and 4 positions of the macrocycle may play an important role in positioning the different chlorophyll chromophores in the thylakoid membranes.

关键词： Chloroplast biogenesis Chlorophyll chromophore Heterogeneity Photosynthesis (HPLC) Chl chlorophyll Chl(ide) a mixture of chlorophyll and chlorophyllide E excitation wavelength f emission wavelength

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SULfHYDRYL-GROUPS IN PHOTOSYNTHETIC ENERGY-CONSERVATION .6. SUBUNIT DISTRIBUTION Of SULfHYDRYL-GROUPS AND DISULfIDE BONDS IN CHLOROPLAST COUPLING fACTOR AND ATPASE ACTIVITY

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BIOCHIMICA ET BIOPHYSICA ACTA 1980年第1期591卷 135-141页

作者： RAVIZZINI, RA ANDREO, CS VALLEJOS, RH NATL UNIV ROSARIO ROSARIO 2000 ARGENTINA

The subunit distribution of sulfhydryl groups and disulfide bonds of spinach chloroplasts coupling factor I was determined. Native coupling factor I with a latent ATPase activity has 8 sulfhydryl groups distributed 4:2:0:0:2 in the .alpha., .beta., .gamma., .delta. and .epsilon. subunits, respectively. Heat treatment of coupling factor I, in addition to the activation of its ATPase activity, induces a dithiol-disulfide interchange between the .gamma. and the .alpha. subunit, changing the sulfhydryl groups'' distribution to 2:2:2:0:2. Reduction of disulfide bonds of coupling factor I by dithioerythritol during heat treatment gives a subunit distribution of 4:4:4:0:2, suggesting that native coupling factor I has 3 disulfide bonds, 2 in the .gamma. subunit and 1 in one of the .beta. subunits. Results suggest an asymmetric redox state of some of the subunits of coupling factor I and an asymmetric positioning of some of them in the molecular structure of coupling factor I.

关键词： Sulfhydryl group Disulfide bonds Subunit distribution Coupling factor I (Spinach chloroplast) Cf 1 chloroplast coupling factor I f 1 mitochondrial coupling factor I Tricine N -tris-(hydroxymethyl)methylglycine SDS sodium dodecyl sulfate

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COMPLEMENTATION Of H-2 LINKED GENETIC-DEfECTS IN THE PRODUCTION AND fUNCTION Of ANTIGEN SPECIfIC SUPPRESSOR fACTOR - IMPLICATIONS fOR SUPPRESSOR-CELL ACTIVATION

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MOLECULAR IMMUNOLOGY 1980年第7期17卷 851-856页

作者： GERMAIN, RN Department of Pathology Harvard Medical School Boston MA 02115 U.S.A.Received 27 September 1979 Available online 12 November 2002

The physiologic basis of gene complementation for T cell mediated immune suppression specific for the synthetic polypeptide l-glutamic50 acid-l-tyrosine50 (GT) ? was investigated. Previous studies had shown that inbre... 详细信息

The physiologic basis of gene complementation for T cell mediated immune suppression specific for the synthetic polypeptide l-glutamic⁵⁰ acid-l-tyrosine⁵⁰ (GT) ? was investigated. Previous studies had shown that inbred mice whose plaque forming cell response to GT coupled to methylated bovine serum albumin (GT-MBSA) is suppressed by prior GT challenge, produce a soluble T cell derived suppressor factor (GT-T_sf), bearing I-J subregion coded determinants which induces a new set of suppressor T cells (T_s2) in virgin spleen cell populations. H-2^a mice, such as A/J, are not suppressed by GT and fail to produce GT-T_sf, but can be suppressed by GT-T_sf via T_s2 induction. H-2^b mice also fail to be suppressed by GT. (B6 × A)f₁ mice show complementation and are suppressed by GT. The present study demonstrates that B6 do produce GT-T_sf, in contrast to A/J mice, but fail to be suppressed by this factor. (B6A)f₁ mice both produce and are suppressed by GT-T_sf. The possible mechanisms (regulatory vs structural) able to account for these findings are discussed

关键词： GAT random terpolymer of l -glutamic acid 60 - l -alanine 30 - l -tyrosine 10 GT random copolymer of l -glutamic acid 50 - l -tyrosine 50 Is immune suppression MBSA methylated bovine serum albumin Mφ macrophage (antigen-presenting cell) PfC plaque forming cell SRBC sheep red blood cells (T,G)-A-L branched chain polymer ( l -tyr, l -glu)- dl -ala- l -lys T H f T cell derived helper factor T s suppressor T lymphocyte T s2 suppressor T cells induced by T s f T s f T cell derived suppressor factor

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ELECTROPHORETIC MOBILITIES Of HUMAN PERIPHERAL-BLOOD LYMPHOCYTES SUB-fRACTIONATED BY PARTITIONING IN 2 POLYMER AQUEOUS PHASE SYSTEMS

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BIOCHIMICA ET BIOPHYSICA ACTA 1980年第1期598卷 193-199页

作者： WALTER, H TAMBLYN, CH LEVY, EM BROOKS, DE SEAMAN, GVf UNIV CALIF IRVINE COLL MEDDEPT PHYSIOLIRVINECA 92717 UNIV OREGON HLTH SCI CTRDEPT NEUROLPORTLANDOR 97201 UNIV BRITISH COLUMBIA DEPT PATHOLVANCOUVER V6T 1W5BCCANADA UNIV BRITISH COLUMBIA DEPT CHEMVANCOUVER V6T 1W5BCCANADA

Mixtures of aqueous solutions of dextran and of poly(ethyleneglycol) form immiscible two-phase systems suitable for the separation (by partitioning) of cells based on subtle differences in their surface properties (Walter, H. (1977) in Methods of Cell Separation (Catsimpoolas, N., ed.), Vol. 1, pp. 307–354, Plenum Press, New York). Human peripheral blood lymphocytes were subjected to countercurrent distribution (a multiple-extraction procedure) in a charged phase system which yields fractions of cells enriched with respect to different surface markers (B-, T- and f c -receptor-bearing) and of different size (Walter, H., Webber, T.J., Michalski, J.P., McCombs, C.C., Moncla, B.J., Krob, E.J. and Graham, L.L. (1979) J. Immunol. 123, 1687–1695). The electrophoretic mobilities of cells in these fractions were measured by means of analytical particle electrophoresis (Bangham, A.D., flemans, R., Heard, D.H. and Seaman, G.V.f. (1958) Nature 182, 642–644). The bulk of B-lymphocytes had not only the lowest partition coefficient (i.e., lowest affinity for the top, positively charged phase) but also the lowest electrophoretic mobility, T-lymphocytes had a higher partition coefficient and mobility, and the population comprising most of the f c -receptor-bearing and largest lymphocytes had the highest partition coefficient but an intermediate mobility. The lymphocytes with highest mobility resolved by countercurrent distribution have yet to be characterized. The results with large and f c receptor-bearing lymphocytes again emphasize that the charges measured by cell electrophoresis and by partitioning are not necessarily the same. They also have as an important, practical consequence that populations enriched with respect to f c -receptor-bearing lymphocytes should be obtainable by a simple one- or two-step extraction process.

关键词： Dextran Poly(ethyleneglycol) Surface properties B-Lymphocyte f c -receptor T-Lymphocyte

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THE PATHOGENESIS Of PSEUDOTUMOR CEREBRI - A MATHEMATICAL-ANALYSIS

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JOURNAL Of THE NEUROLOGICAL SCIENCES 1980年第1期48卷 51-60页

作者： AISENBERG, RM ROTTENBERG, DA MEM SLOAN KETTERING CANC CTR DEPT NEUROLNEW YORKNY 10021 CORNELL UNIV COLL MEDDEPT NEUROLNEW YORKNY 10021

Although the clinical and laboratory features of pseudotumor cerebri have been clearly delineated, the pathogenesis of idiopathic pseudotumor remains a mystery. A number of pathogenetic mechanisms have been proposed to account for some or all of the observed cases. We describe a model relating changes in CSf outflow resistance and/or dural sinus venous pressure to observed changes in (i) CSf pressure, (ii) cerebral blood volume and (iii) the volume and hydrodynamic flow resistance of the ventriculosubarachnoid space.

关键词： CBV cerebral blood volume CSf cerebrospinal fluid CSfP cerebrospinal fluid pressure ICP intracranial pressure I f rate of CSf formation P d dural sinus venous pressure PVI pressure-volume index R a arachnoid villous flow resistance R s flow resistance of the convexity subarachnoid space R 1 s limiting value of R s R t total CSf outflow resistance SVP subarachnoid venous pressure

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16-HYDROXYLATION Of ESTROGENS IN PIGMENTED AND ALBINO GUINEA-PIGS

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JOURNAL Of STEROID BIOCHEMISTRY AND MOLECULAR BIOLOGY 1980年第8期13卷 945-950页

作者： HOBKIRK, R MORI, J NILSEN, M UNIV WESTERN ONTARIO DIV CLIN BIOCHEM DEPT BIOCHEM LONDON N6A 3K7 ONTARIO CANADA

Metabolites of injected [3H]estrone-3-sulfate were investigated in urine, gallbladder bile, liver and kidney of mature pigmented and albino male and non-pregnant female guinea pigs (English Shorthair variety). Considerable formation of estriol, ***.-hydroxyestrone and ***.-hydroxyestrone disulfates, as well as estriol and ***.-hydroxyestrone monosulfates, occurred in pigmented females. Monoglucuronides and monosulfates of estrone and ***. (estradiol) were also observed. No 16-hydroxysteroid monosulfates were detected in pigmented males, but disulfates were present in urine to a lesser extent than for females. No hydroxysteroid monosulfates were found in albinos of either sex and, although small amounts of a disulfate-like fraction occurred in urine, the steroid moieties were not identified. Pigmented females formed lesser amounts of hydroxysteroids from injected [3H]estrone or estradiol than from estrone sulfate. These metabolites were not detected in the other animal groups. Qualitative patterns of estrone and estradiol monoglucuronides and monosulfates were similar in pigmented and albino animals, regardless of the precursor injected.

关键词： 16αOHE 1 16α-hydroxyestrone (3, 16α-dihydroxyestra-1,3,5(10)-trien-17-one) 16KE 2 16-ketoestradiol-17β(3,17β-dihydroxyestra-1,3,5,( 10)-trien-16-one) 16βOHE 1 16β-hydroxyestrone (3, 16β-dihydroxyestra-1,3,5(10)-trien-17-one E 1 estrone E 2 estradiol-17β E 3 estriol 3S denotes sulfate at C-3 3G denotes a glucuronyl group at C-3 diS disulfate of 16-hydroxysteroids f female M male pig. pigmented alb. albino

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INHIBITOR STUDIES Of METHIONYL-TRANSfER RNA TRANSfORMYLASE Of EUGLENA-GRACILIS

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BIOCHIMICA ET BIOPHYSICA ACTA 1980年第1期613卷 73-78页

作者： GAMBINI, A CROSTI, P BIANCHETTI, R UNIV MILAN CNR CTR STUDIO BIOL CELLULARE & MOLEC PIANTE I-20133 MILAN ITALY

Inhibitor studies of the only known eukaryotic methionyl-tRNA transformylase (10-formyltetrahydrofolate:L-methionyl-tRNA N-transformylase, EC 2.1.2.9) were carried out. All the natural pteroylglutamic acid derivatives examined, with the exception of pteroylglutamic acid, are inhibitors. The most effective is 5-methyltetrahydrofolate (5-CH3-H4PteGlu) (KI = 3 .cntdot. 10-6 M), which is the only noncompetitive inhibitor of the enzyme. All the other derivatives tested are competitive, and H4PteGlu shows a cooperative inhibition. These and other data obtained with pteroylglutamic analogs show that, in contrast to the bacterial enzyme, Euglena transformylase is also inhibited by compounds without a fully reduced pyrazine ring and is very sensitive to compounds with a methyl group in position 5 or 10 of the pteridine ring.

关键词： 10-formyltetrahydrofolate: Met-tRNA f transformylase Inhibitor folate metabolism Pteroylglutamate analog (Euglena gracilis)

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AMINO-ACID NEIGHBORHOOD RELATIONSHIPS IN PROTEINS - BREAKDOWN Of AMINO-ACID-SEQUENCES INTO OVERLAPPING DOUBLETS, TRIPLETS AND QUADRUPLETS

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INTERNATIONAL JOURNAL Of BIO-MEDICAL COMPUTING 1980年第1期11卷 67-75页

作者： ERHAN, S MARZOLf, T COHEN, L 2101 Chestnut Street Philadelphia PA 19103 U.S.A.

A method has been developed which allows the breakdown of an amino-acid sequence of proteins into overlapping di-, tripeptides, etc. The frequency of their distribution provides very convincing evidence that these sequences are non-random. These peptides have been demonstrated to be capable of being used as an objective key for the classification of organisms, and of proteins. It is also believed that they can be useful in increasing the accuracy of the prediction of protein folding.

关键词： A alanine C cysteine D aspartic acid E glutamic acid f phenylalanine G glycine H histidine I isoleucine K lysine L leucine M methionine N asparagine P proline Q glutamine R arginine S serine T threonine V valine W tryptophan Y tyrosine

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