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RECIPROCAL INTERACTIONS Of PROGESTERONE AND 17ALPHA-OH-PROGESTERONE AS EXOGENOUS SUBSTRATES Of RAT ADRENAL 21-HYDROXYLASE

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JOURNAL Of STEROID BIOCHEMISTRY AND MOLECULAR BIOLOGY 1976年第10期7卷 761-767页

作者： ORTAfLORES, Z CANTU, JM DOMINGUEZ, OV INST MEXICANO SEGURO SOCIAL RES DEPT EXPTL MED DIV BIOCHEM Mexico City 73 MEXICO INST MEXICANO SEGURO SOCIAL RES DEPT EXPTL MED GENET SECT Mexico City 73 MEXICO

Due to the small concentration and activity of adrenal ***.-hydroxylase, the main corticoids secreted in the rat are DOC, Bk,Ak, 18-OH-DOC [cortexone, corticosterone, 21-hydroxy-4-pregnene-3,11,20-trione and 18-hydroxy-cortexone, respectively] and aldosterone, formed directly from progesterone (I). Because of the limited amounts of ***.-OH-progesterone (II) available, biosynthesis of SR [17,21-dihydroxy-4-pregnene-3,20-dione] fk [cortisol) and Ek [cortisone] is restricted. Since 21-OH steroid hydroxylase (21-OH-ase) uses both I and II in corticoid biosynthesis in other species, it was of interest to study the comparative interactions which could exist between these 2 precursors and rat adrenal 21-OH-ase, determining enzymatic constants for I and II (usual and unusual substrates, respectively). Homogenized adrenals from normal rats were incubated with various combinations of concentrations of 3H-I and/or 14C-II, acting as substrates and/or inhibitors of 21-OH-ase. 21-OH-ase uses II almost as efficiently as I. Km values were about the same for both I and II (13.9 and 14.2 .times. 10-6 M, respectively);however, Vmax values were 54.6 and 26.0 .times. 10-7 M/min for I and II, respectively. Amounts of I required to saturate the 21-OH-ase was double that of II. Both I and II inhibit the 21-hydroxylation of the other in a reciprocal fashion. While II inhibits the 21-hydroxylation of I by competitive inhibition, I inhibits the 21-hydroxylation of II through a mixed type of inhibition. Rather than the existence of 2 different specific enzymes (one for I and another for II) as has been postulated by others, there is probably a 21-hydroxylation system with 2 active sites. One site used only I, and the other site uses I and/or II indistinctively.

关键词： P Progesterone Progesterone 4-Pregene-3,20-dione 17-OH-P 17α-hydroxyprogesterone 17α-hydroxyprogesterone 17α-hydroxy-4-Pregnene-3,20-dione DOC Cortexone Cortexone 21-hydroxy-4-Pregnene-3,20-dione B k Corticosterone Corticosterone 11β,21-dihydroxy-4-pregnene-3,20-dione Aldo Aldosterone Aldosterone 11β,21-dihydroxy-4-pregnene-18-al-3,20-dione f k Cortisol Cortisol 11β,17α,21-trihydroxy-4-pregnene-3,20-dione S R Substance's Reichstem S Substance's Reichstem S Cortexolone Cortexolone 17,21-dihydroxy-4-pregnene-3,20-dione 18-OH-DOC 18-hydroxy-DOC 18-hydroxy-DOC 18,21-dihydroxy-4-pregnene-3,20-dione E k Cortisone Cortisone 17,21-dihydroxy-4-pregnene-3,11,20-trione A k Kendall's Compound A Kendall's Compound A 21-hydroxy-4-pregnene-3,11,20-trione 17α-OH-ase 17α-hydroxylase 21-OH-ase 21-hydroxylase 11β-OH-ase 11β-hydroxylase

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fUNCTION Of PLASTOQUINONE AS ELECTRON AND PROTON CARRIER IN PHOTOSYNTHESIS

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BIOELECTROCHEMISTRY AND BIOENERGETICS 1976年第2期3卷 302-318页

作者： SIGGEL, U TECH UNIV BERLIN MAX VOLMER INSTD-1000 BERLIN 10FED REP GER

The aim of this paper is to compile earlier and recent experimental results by flash photometry in order to discuss the possible mechanisms of coupled proton and electron transport by the plastoquinone system. The results from different techniques ( e.g. fluorescence studies) which sometimes lead to different conclusions are not included.

关键词： AH proton translocator molecule of unknown identity Chl- a 1 and Chl- a II reaction centre chlorophylls of photosystem I and II respectively Cyt- f cytochrome f DCMU 3-(3 4-dichlorophenyl)-I I-dimethylurea MES 2-(N-morpholino)-ethanesulfonate PCy plastocyanine PQ plastoquinone PQH 2 plastohydroquinone PQH . plastosemiquinone PQ .− plastosemiquinone-anion PQ o sum of these 4 species Tricine N-tris (hydroxymethyl)methylglycine U direct acceptor for the electrons of the PQ-pool (mainly PCy) X special plastoquinone not included in the pool X − special plastosemiquinone-anion X 2 2− twin of two X − X 2 o sum of twins of X − and X Y primary electron donor of light reaction II Z primary electron acceptor of light reaction I

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CHOLINE KINASE KINETIC STUDIES - DUAL ROLE Of MG2+ IN SEQUENTIAL ORDERED MECHANISM AT LOW REACTANT CONCENTRATIONS - REGULATORY IMPLICATIONS

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INTERNATIONAL JOURNAL Of BIOCHEMISTRY 1976年第9-10期7卷 483-496页

作者： INfANTE, JP KINSELLA, JE CORNELL UNIV COLL AGR & LIFE SCIITHACANY 14853

The kinetics of the forward reaction catalyzed by choline kinase from rat liver was studied at pH 8.0. The enzyme follows 2 alternative mechanisms according to the concentrations of reactants. Studies at low ligand concentrations are consistent with a sequential order mechanism with the reactants adding in the order: choline, MgATP −2 and Mg 2+ ∗ The apparent and true values of the corresponding kinetic parameters are reported. The possible implications of the dual role of Mg 2+ on the regulation of the activity of this enzyme are discussed.

关键词： [Mg 2+ ] f free Mg 2+ concentration [ATP] i total ATP concentration [Mg 2+ ] i total Mg 2+ concentration [ATP] f free ATP concentration choline kinase or ATP choline phosphoryl transferase (EC 2.7.1.32)

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OLIGOMYCIN SENSITIVITY Of MITOCHONDRIAL ATPASE AS A MARKER fOR fLY TRANSMISSABILITY AND PRESENCE Of fUNCTIONAL KINETOPLAST DNA IN AfRICAN TRYPANOSOMES

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COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY B-BIOCHEMISTRY & MOLECULAR BIOLOGY 1976年第1期55卷 25-30页

作者： OPPERDOES, fR BORST, P DERIJKE, D UNIV AMSTERDAM BIOCHEM LAB MED ENZYMOL & MOLEC BIOL SECT AMSTERDAM NETHERLANDS

The ATPase activity of particulate preparations of 2 strains of Trypanosoma (Trypanozoon) brucei brucei, able to multiply in insects, is highly sensitive to the inhibitor of oxidative phosphorylation oligomycin, although in 1 of these strains no sign of mitochondrial respiratory chain activity was detectable. The ATPase activity of 4 other strains of African trypanosomes, unable to multiply in insects (I- strains), a kinetoplastic strain of Trypanosoma (T.) evansi and dyskinetoplastic variants of T. (T.) evansi and T. (T.) brucei brucei, was insensitive to oligomycin. The ATPase is apparently a mitochondrial enzyme. Its oligomycin sensitivity reflects the presence of a functional kinetoplast DNA and a mitochondrial protein-synthesizing system and, hence, the ability to develop functional mitochondria and to multiply in insects. The analogy between I- trypanosomes and cytoplasmic petite mutants of yeast is stressed.

关键词： K-DNA kinetoplast DNA mtDNA mitochondrial DNA ATPase adenosine triphosphatase (EC 3.6.1.3) Cf 0 membrane factor of mitochondrial ATPase f 1 mitochondrial ATPase

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PLASMA-MEMBRANE PHOSPHORYLATION BY ENDOGENOUS PHOSPHATE DONORS IN HUMAN-BLOOD PLATELETS SELECTIVITY Of ACTION Of DIBUTYRYL CYCLIC-AMP

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BIOCHIMICA ET BIOPHYSICA ACTA 1976年第2期455卷 371-382页

作者： APITZCASTRO, R RAMIREZ, E MAINGON, R DEMURCIANO, A RIBBI, A INST VENEZOLANO INVEST CIENTIFICAS CTR BIOFIS & BIOQUIM CARACAS 101 VENEZUELA

Incubation of platelet-rich plasma with 32Pi leads to cellular uptake of the isotope and covalent incorporation into several cell constituents. Plasma membranes isolated from intact labeled platelets, delipidated and solubilized in sodium dodecyl sulfate, show, upon gel electrophoretic analysis, 3 main peaks of radioactivity: 2 in the MW range 100,000-30,000 and an additional very slow migrating component strongly positive by the periodic acid-Schiff reaction. Treatment of the cells with dibutyryl cyclic AMP under conditions just sufficient to completely inhibit platelet aggregation leads to an increased isotope incorporation. Electrophoretic analysis of membranes isolated from dibutyryl cyclic AMP-treated cell reveals: no change in the general pattern of distribution of the isotope;no difference in the isotope incorporation to the 2 components of lower molecular weight and a marked increase (> 100%) in isotope incorporation in the slow migrating material as compared to membranes isolated from control cells. This material can be extracted from platelet plasma membranes after treatment of the membranes for 5 h with Triton X-100, at a detergent-to-protein ratio of 7.5. When the membrane material extracted with Triton X-100 is subjected to gel chromatography in Agarose (Biogel A-15m), the phosphorylated material that corresponds to the slow migrating band in polyacrylamide gel electrophoresis is eluted with or very close to the void volume of the column. Isoelectric focusing of this fraction shows a single radioactive peak corresponding to an isoelectric point of 3.78. The isolated component is pronase-sensitive, contains 52% of carbohydrate and 15% sialic acid. Analysis of the stability of the bound phosphate suggests that about 43% of it is bound as acylphosphate. The results, obtained through an approach that closely resembles physiological conditions, are compatible with the participation of this membrane phosphoglycoprotein in the phenomena of platelet aggregation

关键词： cyclic AMP adenosine 3′ : 5′-cyclic monophosphate dibutyryl cyclic AMP N 6 ,O 2′ -Dibutyryl adenosine 3′ : 5′-cyclic monophosphate PheMeSO 2 f phenylmethyl-sulfonylfluoride TosPheCH 2 Cl l -1-tosylamide-2-phenylethyl-chloromethyl ketone TosylCH 2 Cl N -α-p- tosyl- l -lysine chloromethyl ketone

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EffECTS Of GUANIDINE-HYDROCHLORIDE ON HUMAN-PLASMA HIGH-DENSITY LIPOPROTEINS

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BIOCHIMICA ET BIOPHYSICA ACTA 1976年第1期446卷 226-239页

作者： NICHOLS, AV GONG, EL BLANCHE, PJ fORTE, TM ANDERSON, DW UNIV CALIF BERKELEY LAWRENCE BERKELEY LAB DONNER LAB BERKELEY CA 94720 USA

Denaturation of human plasma high density lipoproteins during ultracentrifugation in *** is characterized by dissociation of apoA-I, in the range of 2-3 M *** and dissociation of apoA-I and apoA-II in 5-6 M ***. Denaturation of high density lipoprotein species, during a sequence of timed exposure to *** followed first by removal of the denaturant by dialysis and then by ultracentrifugation, is characterized by dissociation of lipid-poor apoA-I, which follows a time course similar to denaturation-related changes in reported spectroscopic parameters, and apparent formation of lipoprotein aggregation products depleted in apoA-I and relatively enriched in apoA-II. These studies indicate differential properties of the major apoproteins in stabilizing high density lipoprotein structure, and characterize a mode of lipoprotein transformation and degradation which apparently results from apoprotein dissociation coupled with aggregation of denatured lipoprotein species.

关键词： HDL high density lipoproteins isolated between d  1.063 and 1.21 g/ml HDL 2 HDL isolated between d  1.063 and 1.125 g/ml HDL 3 HDL isolated between d  1.125 and 1.21 g/ml apoA-I and apoA-II two major apoproteins from human HDL, both with carboxyl-terminal glutamine. f 1.20 values are flotation rates expressed in Svedbergs (10 −12 cm/s/dyne/g) in a NaBr/NaCl solution of density 1.20 g/ml

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SELECTIVE SOLUBILIZATION Of COMPONENTS Of MITOCHONDRIAL INNER MEMBRANE BY LYSOLECITHIN

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BIOCHIMICA ET BIOPHYSICA ACTA 1976年第1期455卷 24-35页

作者： RYDSTROM, J UNIV STOCKHOLM DEPT BIOCHEMARRHENIUS LABS-10405 STOCKHOLMSWEDEN

1. 1. Of various phospholipids tested, lysolecithin was the most efficient in the solubilization of the components of beef heart submitochondrial particles. Lysolecithin solubilized selectively nicotinamide nucleotide transhydrogenase, succinate dehydrogenase, NADH dehydrogenase and oligomycin-sensitive ATPase. Various cytochromes other than cytochrome c were only slightly solubilized. 2. 2. The effect of various parameters, e.g. ionic strength, pH, time of centrifugation, and concentrations of lysolecithin and protein was investigated. Increasing times of centrifugation led to a partial sedimentation of NADH dehydrogenase, and a complete sedimentation of oligomycin-sensitive ATPase and cytochrome oxidase. 3. 3. further fractionation of the lysolecithin extract by centrifugation in the presence of low concentrations of cholate gave a complete separation of NADH dehydrogenase and transhydrogenase, indicating that these enzymes are not related functionally. 4. 4. With the lysolecithin fractionation procedure a more than 10-fold purification of transhydrogenase was achieved. Polyacrylamide gel electrophoresis of the partially purified transhydrogenase in the presence of sodium dodecyl sulphate showed major increases in protein-stained bands corresponding to between 70 000 and 54 000 daltons. 5. 5. A possible mechanism for the detergent action of lysolecithin involving a specific exchange of bound phospholipids for lysolecithin is discussed.

关键词： f 1 ATPase (coupling factor 1)

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PROTEINASES Of HUMAN EPIDERMIS - POSSIBLE MECHANISM fOR POLYMORPHONUCLEAR LEUKOCYTE CHEMOTAXIS

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BIOCHIMICA ET BIOPHYSICA ACTA 1976年第2期452卷 458-467页

作者： LEVINE, N HATCHER, VB LAZARUS, GS DUKE UNIV MED CTR DEPT MED DIV DERMATOL DURHAM NC 27710 USA MONTEFIORE HOSP & MED CTR DIV DERMATOL BRONX NY 10467 USA YESHIVA UNIV ALBERT EINSTEIN COLL MED DEPT BIOCHEM BRONX NY 10461 USA YESHIVA UNIV ALBERT EINSTEIN COLL MED DEPT MED BRONX NY 10461 USA

Three neutral proteinases (EC 3.4.-.-) and cathepsin D were identified in human epidermis utilizing a highly sensitive radioactive method. The proteinases were extracted in 1.0 M KCl and 0.1% Triton X-100 and separated by Sephadex G-75 chromatography. The neutral proteinase peaks were all inhibited by diisopropyl fluorophosphate and thus were serine proteinases. Incubation of the enzyme fractions with [3H]diisopropyl fluorophosphate followed by sodium dodecyl sulfate polyacrylamide gel electrophoresis demonstrated that the 2 larger molecular weight proteinases were enzyme mixtures. The small molecular weight [3H]diisopropyl fluorophosphate proteinase migrated as a single band. Injection of the small molecular weight neutral proteinase into rabbit skin produced a polymorphonuclear leukocyte infiltration and edema. The reaction was not observed with the diisopropyl fluorophosphate-inhibited enzyme fraction. The release of neutral proteinases may be one of the singal events in the epidermal inflammatory response.

关键词： iPr 2 P- f diisopropyl fluorophosphate

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ISOLATION AND PARTIAL CHARACTERIZATION Of 2 ABNORMAL HUMAN-PLASMA LIPOPROTEINS - LP-X-1 AND LP-X-2

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BIOCHIMICA ET BIOPHYSICA ACTA 1976年第2期434卷 419-427页

作者： PATSCH, JR PATSCH, W SAILER, S BRAUNSTEINER, H METHODIST HOSP HOUSTON TX 77030 USA UNIV INNSBRUCK DEPT MED A-6020 INNSBRUCK AUSTRIA

Two abnormal lipoproteins (LP-X1 and LP-X2) rich in free cholesterol and phospholipid were isolated from the plasma of 9 different patients with obstructive jaundice. As isolated, both lipoproteins were devoid of low density lipoproteins as judged by agar electrophoresis. In addition, they were free of apoB as judged by double immunodiffusion. However, LP-X1 exhibited a higher phospholipid to protein ratio and a lower hydrated density than LP-X2. The levels of LP-X1 and LP-X2 in plasma were measured in 3 patients studied for 14 days after corrective surgery for obstructive liver disease. The level of both these abnormal lipoproteins decreased after surgery until the 12th day when they were completely absent from the plasma of these patients. The rates of this decrease for the 2 particles are significantly different. These differences in metabolic, chemical and physical properties of LP-X1 and LP-X2 establish their identity as 2 distinct and unique lipoprotein particles.

关键词： VLDL very low density lipoproteins isolated conventionally at density 1.006 g/ml and under our zonal ultracentrifugation conditions at density <1.02 g/ml LDL low density lipoproteins isolated conventionally between densities 1.006 and 1.063 g/ml and by our zonal procedure in the density range 1.05–1.10 g/ml and containing apoB HDL high density lipoproteins conventionally isolated at density 1.063–1.210 g/ml and by our zonal procedure at the periphery (bottom) of the rotor [10] LP-X 1 abnormal lipoproteins from the plasma of patients with obstructive liver disease isolated under our zonal ultracentrifugation conditions in the density ranges 1.04–1.06 LP-X 2 abnormal lipoproteins from the plasma of patients with obstructive liver disease isolated under our zonal ultracentrifugation conditions in the density ranges 1.06–1.08 g/ml conventionally at density 1.006–1.063 g/ml apoB a major protein component of VLDL and LDL S f flotation rate in an aqueous sodium chloride solution of density 1.063 g/ml at 26 °C

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ISOLATED, RADIOIODINATED SURfACE IMMUNOGLOBULINS Of MURINE BONE-MARROW DERIVED LYMPHOCYTES WHICH BIND 2,4-DINITROPHENYL HAPTEN

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IMMUNOCHEMISTRY 1976年第8期13卷 667-670页

作者： MARCHALONIS, JJ ROY MELBOURNE HOSP WALTER & ELIZA HALL INST MED RESMOLEC IMMUNOL LABMELBOURNE 3050VICTORIAAUSTRALIA

Radioiodinated surface proteins of B cells of unimmunized congenitally thymic aplastic nu/nu mice which bound to dinitrophenylated cellular or Sepharose immunoadsorbents were isolated and partially characterized. Antigenic analysis and polyacrylamide gel electrophoresis in sodium dodecylsulfate-containing buffers disclosed that surface immunoglobulins of IgM and putative IgD type were the major DNP-binding proteins. Another component characterized by an electrophoretic mobility corresponding to that of a previously described protein which binds to antigen-antibody complexes was also observed. The surface Ig which bound to DNP was a subpopulation comprising <5% of total B cell surface Ig. These results support the concept that two types of B cell surface Ig molecules serve as recognition units for antigen.

关键词： B cells bone-marrow-derived lymphocytes BSA bovine serum albumin DNP dinitrophenol f x -SRBC dinitrophenylated fixed sheep erythrocytes SRBC sheep erythrocytes Ig immunoglobulin NIP nitroiodophenol PAGE polyacrylamide gel electrophoresis SDS sodium dodecylsulfate

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