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SCIENCE teachers, TEACHER training, CHEMISTRY education, HIGH schools, OCCUPATIONAL training, SECONDARY education, EFFECTIVE teaching, HIGH school students, and EDUCATION research

The article discusses studies about developments in professional training of science teachers in high schools in the U.S. A chemistry teacher should have as a minimum, college courses in general inorganic chemistry, organic chemistry, qualitative analysis, quantitative analysis and physical chemistry. Organic chemistry is studied because of the basic principles and general information involved and the important role organic substances play in modern life. One of the conclusions reached by the Committee on Preparation of High School Chemistry teachers is that more extensive training and other sciences is urgently needed in many cases and these needs should be met either by decreasing the requirements in educational course, by increasing the number of credits required for graduation.

SCIENTISTS, BIOLOGISTS, BIOLOGICAL research, SCIENTIFIC community, and OXYTETRACYCLINE

The article presents information on scientist Ben A. Sobin and his research achievements. He was born in Cleveland, Ohio, in 1912 and his graduate education took place at Ohio State University. He specialized in chemistry, organic chemistry, bacteriology and biochemistry. Professionally he worked in various organizations and his career with Pfizer Inc. began as chief of biologies control where he attained success in research assignment. One of them was the preparation of the first samples of Terramycin under Sobin's direction.

BIOCHEMISTRY, CHEMICAL abbreviations, NAMES, ORGANIC chemistry, BIOLOGY, CHEMISTRY, and SCIENCE conferences

The Commission on the Nomenclature of Biological Chemistry decided in 1958 that an attempt should be made to standardize the abbreviations and symbols used for chemical names of special interest in biological chemistry. The original draft proposals were based on the notes given at the beginning of each number of the Journal of Biological Chemistry. The problems were discussed fully at the meeting of the commission in Munich in September 1959--and also in joint sessions with the Organic Nomenclature Commission and the Enzyme Commission of the International Union of Biochemistry. A third draft, incorporating the results of the Munich discussions, was widely circulated in December 1959, and many useful comments on this were received.

LIPIDS, NAMES, BIOCHEMISTRY, ORGANIC chemistry, BIOMOLECULES, and STEROIDS

The nomenclature of lipids is the concern both of organic chemists and of biochemists. The systematic names of individual lipids can always be derived by the general rules of organic nomenclature, however, such names are often complex and need to be supplemented by alternative "semi systematic" names as has been done, for steroids and corrinoids. Another problem is that of names for groups of related and homologous compounds including mixtures, such names are hardly ever needed by the pure organic chemist, but are very necessary in biochemical work.

BASIC dyes, CELL membranes, THERMODYNAMICS, ORGANIC chemistry, and MITOCHONDRIA

Three effects concerning the organic cations, the aggregation, the metachromasy and the pKa shift, have been studied in comparison at high dye concentrations, with natural and synthetic polyanions and with energized submitochondrial particles. The metachromatic effect has been obtained by increase of the free cationic dye concentration or by interaction of the dye with natural, synthetic polyanions and energized submitochondrial particles. The metachromatic effect is dependent on the pH of the medium, the presence of ionized acidic groups, and the ionic strength of the medium. The polyanion-induced metachromasy requires the ionization of the acidic groups of the polyelectrolyte. The metachromasy with neutral red requires an acidic pH if induced by increase of the dye concentration or by chondroitin sulphuric acid, whereas it takes place also at alkaline pH if induced by polystyren suiphonic acid or by energized particles. It is inhibited by increase of ionic strength in the case of agar and chondroitin sulphuric acid, but not in the case of the energized particles or polystyrene sulphonic acid. Interaction of neutral red with polystyrene sulphonic acid or energized particles results also in a large apparent pKa shift, which represents the mechanism for obtaining the metachromatic effects at alkaline pH. The apparent pKa, as measured from the extinction of the alkaline band is: 6.0 at 400µM neutral red, 6.7 at 20 µM neutral red, 7.0 with chondroitin sulphuric acid, 7.1 with the deenergized particles, 8.0 with polystyrene sulphonic acid and 8.1 with energized particles. From thermodynamic considerations it is suggested that the pKa shift requires a decrease of the activity coefficient of the dye following the formation of ion pairs with anionic groups of the membrane. The pKa shift may be taken as a tool for discriminating between a dyeinduced and a membrane-induced metachromatic effect. A model is proposed for the energized membrane, based upon electrostatic and hydrophobic interactions of the cationic dyes with a layer of oriented nucleophilic sites in an environment of intermediate polarity. [ABSTRACT FROM AUTHOR]

AMINO acids, NAMES, POLYMERS, FUNCTIONAL groups, PEPTIDES, and ORGANIC chemistry

The article presents information about nomenclature of wide variety of synthetic polypeptides. Linear polymers are all amino acid residues linked in an unbranched chain. Block is a polymer that forms a distinct part of a larger polymer. In Graft polymer, one or more blocks are linked to the functional groups of a linear polymer, thus creating a branch or branches. In block polymer, two or more species of block are linked to form a larger linear polymer. Abbreviated nomenclature of synthetic polypeptides is given in detail along with several examples.

CAROTENOIDS, BIOLOGICAL pigments, TERPENES, PIGMENTS, ORGANIC chemistry, and CHEMISTRY

Details the amendments to the nomenclature of carotenoids developed by the UPAC Commission on the Nomenclature of Organic Chemistry and the IUPAC-IUB Commission on Biochemical Nomenclature. Minor changes; Points of scientific interest; Certain compounds that arise from certain rearrangements or degradations of the carbon skeleton.

AMINO acid separation, HYDROLYSIS, GLYCOPROTEINS, BIOCHEMISTRY, ORGANIC chemistry, and CHEMISTRY

The acylneuraminic acid fraction, obtained on mild acid hydrolysis of glycoproteins from bovine submandibular glands, contains approximately 2% N-acetyl-9-O-L-lactylneuraminic acid. The com- pound has been isolated and purified by ion-exchange and cellulose column chromatography. The structure has been elucidated using thin-layer chromatography, colorimetry, gas-liquid chromatography/mass spectrometry, periodate oxidation and specific lactate dehydrogenases. An evaluation of the different analytical methods is given. [ABSTRACT FROM AUTHOR]

ORGANIC chemistry, NAMES, BIOCHEMISTRY, and BIOORGANIC chemistry

Presents information on the nomenclature of organic chemistry. System of naming for natural products and related compounds; Structures for semisystematic names; Basis for the name of the natural product.

PHYSICAL & theoretical chemistry, ORGANIC chemistry, NAMES, BIOCHEMISTRY, and BIOORGANIC chemistry

Presents the nomenclature of isotopically modified chemical compounds. Symbols of compounds; Definitions and formulas of various types of isotopic modification; Choice between isotopically modified and unmodified atoms or groups.

ORGANIC solid state chemistry and SOLID state chemistry

Examines the electronic properties of organic solids. Uses of organic polymers; Spatial variations in the local composition and structure; Molecular nature of organic solids.

PROTEIN fractionation, ISOELECTRIC focusing, ELECTROPHORESIS, ORGANIC chemistry, QUALITATIVE chemical analysis, BIOCHEMISTRY, CHEMISTRY, and MEDICAL sciences

1. Proteins of fat-globule membrane from bovine milk were solubilized with the non-ionic detergent Triton X-100 in the presence of protease inhibitors. Approximately 25% of the total membrane protein was solubilized and the extracts were shown to contain a sample of most of the major membrane proteins and glycoproteins. 2. The solubilized proteins were separated in flat-beds of Ultrodex by electrofocusing and the pI values for the major proteins, glycoproteins and certain enzymes determined. Several of the proteins displayed marked heterogeneity indicating the existence of protein variants and isoenzymes. Principal pl values for the enzymes assayed were as follows: xanthine oxidase, 7.35–7.55; NADH2:iodonitrotetrazolium reductase, less than 4.5; 5′-nucleotidase, 7.15–7.4; alkaline phosphatase, 5.4–5.7; phosphodiesterase, 4.6–4.8; γ-glutamyl transpeptidase, 4.4–4.55. 3. Fractions after electrofocusing were analyzed by ‘fused rocket’ immunoelectrophoresis and crossed immunoelectrophoresis after separation in polyacrylamide gels containing sodium dodecyl sulphate. Major antigens of the membrane include xanthine oxidase and glycoproteins of apparent molecular weights 67000, 49500 and 46000. The latter two components share common antigenic determinants and could not be separated by gel filtration, ion-exchange chromatography, lectin-affinity chromatography or preparative electrofocusing. [ABSTRACT FROM AUTHOR]

ENZYMES, CYTOCHROMES, ELECTROPHORESIS, HYDROGEN-ion concentration, ISOELECTRIC focusing, QUALITATIVE chemical analysis, and ORGANIC chemistry

Methemoglobin reduction in human red cells involves successively an electron transport from NADH to a soluble form of cytochrome b5 (step 1) and from cytochrome b5 to methemoglobin (step 2), Step 1 is catalysed by an enzyme, soluble NADH:cytochrome b5 reductase (EC 1.6.2.2). Step 2 is non-enzymatic and involves complementary electrostatic interactions between acidic residues of cytochrome b5 and basic residues of hemoglobin [Gacon et al. (1980) Proc, Natl Acad. Sci. USA, 77, 1917–1921], Here we present data indicating a similar mode of interactions occurring in step 1 between cytochrome b5 reductase and cytochrome b5. These results have been obtained by using the combined isoelectric focusing/electrophoresis method [Righetti et al. (1978) J. Chromatogr. 166, 455–460] allowing a direct titration of both entities either separately or in a mixture. This is the first report on the obtention of a direct titration curve of an enzyme visualized after specific staining (zymogram). The pH dependence of the Michaelis constant for cytochrome b5 is also in agreement with the hypothesis that electrostatic charges, which are maximal below pH 7.0, are essential in the interaction between cytochrome b5 and its reductase. [ABSTRACT FROM AUTHOR]

ACETYLTRANSFERASES, ENZYMES, TRANSFERASES, PROTEIN metabolism, AMINO acids, LABORATORY rats, and ORGANIC chemistry

The charge heterogeneity of the mitochondrial acetyl-CoA acetyltransferase (EC 2.3.1.9), referred to transferases A and B, seems to be preformed in vivo and can be demonstrated in vitro by a spontaneous transformation of transferase A into transferase B. These two enzymes, although remarkably similar in amino acid composition, show structural dissimilarities. This becomes evident from their tryptic maps, which are substantially different. Isoelectric focusing in the presence of urea confirms the charge heterogeneity of the mitochondrial acetyl-CoA acetyltransferase by indicating different patterns of protein bands for transferases A and B. Transferase B lacks the protein band with an isoelectric point of 7.2 which is normally shown with transferase A. However, this 7.2-pI protein band can be demonstrated after a [³H]CoASH treatment of transferase B in the presence of urea by protein staining and by autoradiography. This change in the isoelectric focusing band pattern after interaction of the subunits with CoASH is interpreted as being the result of an apparently covalent secondary modification of the protein side chains. The CoASH-modification may be the only molecular basis of the acetyl-CoA acetyltransferase charge heterogeneity, a view, which is further substantiated by the CoASH-mediated transformation of transferase B into transferase A. An additional heterogeneity of the enzyme as caused by a limited proteolysis seems unlikely but cannot be definitely excluded. [ABSTRACT FROM AUTHOR]

CHEMICAL purification, ANGIOTENSINS, OLIGOPEPTIDES, LABORATORY rats, PROTEIN analysis, ORGANIC chemistry, and BIOCHEMISTRY

Two forms of rat plasma proangiotensin were purified by (NH4)2SO4 fractionation, chromatography on DEAE-cellulose at pH 6.5, DEAE-Sepharose at pH 8.9, Sephadex G-150, hydroxyapatite and hexyl-agarose. Both forms were finally separated by affinity chromatography on concanavalin-A—Sepharose. Presence or absence of carbohydrate side chains seems to be the only difference between these forms of proangiotensin. Both proteins consist of single polypeptide chains having apparent molecular weights of 52000 and 55000 and isoelectric points around 4.7 and 4.4, respectively. No significant difference between the proteins could be observed with respect to the amino-terminal amino acid sequence which was found to be the same (H2N-Asp-Arg-Val) as for angiotensin I and II. Furthermore, extensive digestion with renin, releasing the decapeptide angiotensin I, did not significantly reduce the molecular weights of both polypeptides. It can therefore be concluded that the angiotensin I peptide is located at the amino terminus of the prohormone. Kinetic constants measured for the release of angiotensin I by renin were found to be Km = 5.0 μM proangiotensin and V = 270 nmol of angiotensin I h-1 unit renin-1 for the concanavalin-A-binding form and Km = 5.6 μM proangiotensin and V = 250 nmol angiotensin I h-1 unit renin-1 for the prohormone which did not bind to concanavalin-A—Sepharose. The form of proangiotensin not bound to concanavalin-A—Sepharose was found to be more thermally labile (tm of 59.0 °C) than the form binding to concanavaiin A (tm of 61.5 °C, where tm = temperature at which 50% reactivity is lost). [ABSTRACT FROM AUTHOR]

CHEMICAL nomenclature, BIOCHEMISTRY, ORGANIC chemistry, AMINO acids, PEPTIDES, NUCLEOTIDES, and ENZYMES

Lists the recommendations of the nomenclature committees of the IUB Committee of Editors of biochemical journals and other international committees. General nomenclature; Organic chemistry nomenclature; Amino acids; Peptides; Proteins; Enzymes; Nucleotides.

X-ray crystallography, BINDING sites, FLAVINS, ORGANIC chemistry, MONOOXYGENASES, and MOLECULES

Analysis of the partially refined X-ray crystallographic structure of the active site of p-hydroxybenzoate hydroxylase shows clearly that the enzyme is complementary to a flavin C4,C4a-dioxetane derivative. A mechanism is proposed based on such an intermediate as the oxenoid transferring agent. A non-enzymatic analogue of this reaction is not known in organic chemistry. A possible evolutionary pathway for such a non-imitable enzyme is discussed. [ABSTRACT FROM AUTHOR]

ORGANIC chemistry and RESEARCH

Focuses on the contributions of Jean Baptiste Dumas to organic chemistry research in France. Description of the Dumas school; Assessment of the relationship between Dumas and his students; Formation of a laboratory-based research school.

ISOELECTRIC focusing, ELECTROPHORESIS, ORGANIC chemistry, IMMUNOGLOBULINS, GLOBULINS, CRYOGLOBULINEMIA, and PARAPROTEINEMIA

Previous studies have demonstrated that the IgM monoclonal anti-IgG autoantibodies (AGAs) characteristic of essential mixed cryoglobulinaemia (EMC) display preferential use of κ light chains of the Vkiiib sub-subgroup. In order to gain insights as to the possible basis for this V region selection, IgM-Vkiiib immunoglobulin was affinity purified from normal human serum, analysed by dissociating two-dimensional gel electrophoresis and compared to the two-dimensional gel patterns of IgM-Vkiiib anti-IgG autoantibodies (AGAs) from patients with essential mixed cryoglobulinaemia (EMC). The results suggest that only part of the available Vkiiib light chain repertoire is selected by EMC AGAs. When AGAs from EMC, rheumatoid arthritis (RA) and primary Sjögren's syndrome (SS) patients were analysed by ELISA, it was found that the association of Vkiiib light chains with anti-IgG autoantibodies differed significantly among the three diseases. In fact, in RA there appeared to be a negative selection against the use of Vkiiib in AGAs. Clearly, the Vkiiib determinant is not required for anti-IgG autoreactivity. The possibility emerges, therefore, that the genesis and perpetuation of AGA synthesis in these diseases may follow quite different pathways. [ABSTRACT FROM AUTHOR]

ORGANIC compounds, SULFUR, CHEMISTRY, ORGANIC chemistry, ALCOHOLS (Chemical class), and CARBOHYDRATES

Five complex hopanoids have been detected in the purple non-sulfur bacterium Rhodopseudomonas acidophila. Next to the polyfunctionalized methylcyclopentane bacteriohopanetetrol ether already isolated from Methylo- bacterium organophilum, 3 5-carbamoylbacteriohopane-32 ,3 3,34-trio!, 34,3 5-dicarbamoyl bacteriohopane-3 2,33 - diol and two nucleoside analogues, (22R)-30-(5'-adenosyl)hopane and (223)-30-(5'-adenosyl)hopane were isolated and identified by spectroscopic and chemical methods. In Rhodopseudomonas palustris, however, only 3 5-amino- bacteriohopane-32,33,34-triol was detected. Chemical correlation between adenosyihopane and bacteriobopanetetrol, as well as comparison of derivatives obtained from bacterial and synthetic hopanoids, permitted the determination of the configurations of all asymmetric centres of the side-chain of bacteriohopanetetrol as 22R, 32R, 33R and 34S. According to the stereochemistry, this side-chain could be a D-ribose derivative linked through its C-5 carbon atom to the hopane skeleton. [ABSTRACT FROM AUTHOR]

ISOELECTRIC focusing, CELL proliferation, MOLECULAR weights, FLUIDS, ELECTROPHORESIS, and ORGANIC chemistry

We investigated the possible existence of IL-1 in human amniotic fluid (AF). Since AF from most full- term deliveries appeared to contain an inhibitor(s) for thymocyte proliferation, AFs were fractionated by gel filtration prior to IL- 1 assay. IL-1 activities eluted in two peaks at positions of 90,000-60,000 MW and 20,000-15,000 MW. Growth inhibitory activity eluted at the position of 70,000-50,000 MW, and its effect appeared to be non-specific because these fractions inhibited the growth of various cell lines. Using isoelectric focusing (IEF) techniques, pI values of 68-7.3 for the higher MW IL-1 as well as 4.9-5.5 and 6.7-7.0 for the lower MW IL-1 were obtained. Antibody against human IL-1α partially neutralized the activity of the lower MW IL-1, though it exhibited little effect on the higher MW IL-1. In contrast, antibody against human IL-1β almost completely neutralized the activity of the higher MW IL-1 and partially neutralized the activity of the lower MW IL-1. These results suggest that most of the higher MW IL-1 is β-type, and the lower MW IL-1 is a mixture of α and β-types. IL-1 β appeared to exist as a complex (combined with AF components) or as an aggregate of the lower MW IL-1 forms. These findings indicate that both IL-1α and IL-1β are present in normal human AF from full-term deliveries, though IL-1β exists as a higher MW form aggregated with an unknown molecule. [ABSTRACT FROM AUTHOR]

SKIN absorption, ORGANIC solvents, GUINEA pigs, SURFACE active agents, ORGANIC compounds, and ORGANIC chemistry

Percutaneous absorption of 4 organic solvents (1,1,1-trichloroethane, 1,1,2-trichloroethane, toluene and butanol) from various colloidal preparations in a surfactant-water-organic solvent system was studied in vivo in guinea pigs. The preparations examined were binary solutions of organic solvents and surfactants, o/w emulsions and microemulsions. Phase diagram, birefringence microscopy and droplet size: distribution analysis were used for characterization of the preparations. It was found that skin absorption of the solvents depends on the type of surfactant, type of preparation and also on phase equilibria in the systems studied. The presence of nonionic surfactants in the solvents and in a microemulsion with butanol caused skin absorption to decrease. A reduced uptake of solvents from o/w emulsions was observed. The absorption of butanol from a microemulsion with anionic surfactant was greater than from the pure solvent. [ABSTRACT FROM AUTHOR]

AMINO acids, PROTEINS, FLAVINS, NUCLEAR magnetic resonance, BIOCHEMISTRY, and ORGANIC chemistry

Assignments for the 137 amino acid residues of Megasphaera elsdenii flavodoxin in the reduced state have been made using the sequential resonance assignment procedure. Several hydroxyl and sulfhydryl protons were observed at 41 °C at pH 8.3. Spin systems were sequentially assigned using phase-sensitive two-dimensional-correlated spectroscopy and phase-sensitive nuclear Overhauser enhancement spectroscopy. Spectra of the protein in H2O and of protein preparations either completely or partly exchanged against ²H2O were obtained. Use of the fast electron shuttle between the paramagnetic semiquinone and the diamagnetic hydroquinone state greatly simplified the NMR spectra, making it possible to assign easily the ¹H resonances of amino acid residues located in the immediate neighbourhood of the isoalloxazine ring. The majority of the nuclear Overhauser effect contacts between the flavin and the apoprotein correspond to the crystal structure of the flavin domain of Clostridium MP flavodoxin, but differences are also observed. The assignments provide the basis for the structure determination of M. elsdenii flavodoxin in the reduced state as well as for assigning the resonances of the oxidized flavodoxin. [ABSTRACT FROM AUTHOR]

PROTEOGLYCANS, AMINO acids, ENZYME-linked immunosorbent assay, ORGANIC chemistry, IMMUNOLOGY, and BIOCHEMISTRY

Two populations of proteochondroitins were isolated from 4 M guanidine hydrochloride extracts of squid skin by a combination of ion exchange, gel chromatography and density gradient centrifugation. The proteoglycans, Mr 4.8 × 105 and 2.8 × 105, contained four and two chondroitin chains respectively and unusual oligosaccharides with uronic acid and sulphate groups, and had different amino acid and neutral sugar composition. The chondroitin chains isolated after alkaline borohydride treatment contained varying amounts of glucose, galactose, mannose, fucose and xylose, most likely as branches. Both proteoglycans were antigenic to the rabbit and showed considerable cross-reactivity as assessed by competition experiments using the ELISA technique. The proteoglycans reacted neither with exogenous hyaluronic acid nor with each other to form aggregates. [ABSTRACT FROM AUTHOR]

ORGANIC chemistry and PETROLEUM

ORGANIC chemistry and PETROLEUM