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This article discusses paper electrophoresis patterns of enzymes involved in polyglucoside synthesis in oscillatoria princeps and its low temperature strains. The technique of paper partition chromatography and paper electrophoresis for the study of genetically different tissues have recently found application in the field of genetic studies. These methods should prove of considerable interest in the detection of differences between enzymes having the same properties and functions in the different species.

The role of Β-glucose 1,6-bisphosphate as a cofactor in the reaction catalyzed by the phosphoglucomutase for Β-glucose 1-phosphate (Β-phosphoglucomutase) has been examined in purified extracts of Euglena gracilis var. bacillaris. 1. The incubation of Β-glucose 1-[32P]phosphate with Β-phosphoglucomutase in presence of high concentrations (0.1 mM) of a commercial preparation of α-D(+)-glucose 1,6-bisphosphate (prepared synthetically) yielded a labelled compound running electrophoretically and chromatographically as the sugar bisphosphate. Specificity studies with Β-phosphoglucomutase and muscle phosphoglucomutase (α-phosphoglucomutase) strongly suggest that the compound formed is Β-glucose 1,6-[32P]bisphosphate. The results would also indicate that the commercial preparation of α-D(+)-glucose 1,6-bisphosphate contains Β-glucose 1,6-bisphosphate as contaminant. 2. When synthetic Β-glucose 1-phosphate preparations were purified by paper chromatography and then incubated with Β-phosphoglucomutase, no glucose 6-phosphate could be detected. On the other hand the reaction readily took place when challenged with the chromatographic fraction that runs as sugar bisphosphate. Upon analysis with etectrophoresis, chromatography and weak acid hydrolysis, and experiments with Β-phosphoglucomutase and α-phosphoglucomutase it was concluded that this compound is Β-glucose 1,6-bisphosphate. 3. It was established that the natural α-D(+)-glucose 1,6-bisphosphate not only fails to sustain the reaction catalyzed by Β-phosphoglucomutase but rather inhibits the reaction when added to the whole Β-phosphoglucomutase system, it was also demonstrated that Β-glucose 1,6-bisphosphate acts as inhibitor of the α-phosphoglucomutase system. 4. These results show for the first time that Β-glucose 1,6-bisphosphate is an active and necessary participant in the reaction catalyzed by Β-phosphoglucomutase. The role played by Β-glucose 1,6-bisphosphate in this reaction would be essentially the same as that of the α-anomer in the reaction catalyzed by α-phosphoglucomutase. [ABSTRACT FROM AUTHOR]

A conference paper on the electrochemistry of porous membranes is presented. It discusses the selectively permeable role played by the porous membrane in molecular, ionic, and particle transport. The composition and mechanisms of membranes are described and research performed on the dynamics of membrane systems is examined.

An apparatus for electrophoresis on cellulose coated glass plates is described. Combined with a subsequent chromatographic separation, thin-layer electrophoresis permits a rapid, convenient and complete analysis of the amino acid composition of various biological fluids and extracts. Relative mobility values and Rf-values are given for 21 of the more common acids and amines. [ABSTRACT FROM AUTHOR]

The ATP-synthesis and the electric phenomena on the thylakoid membrane have been studied under excitation of photosynthesis with short flash groups. The light induced electric potential difference has been measured by means of field indicating absorption changes around 523 nm. It is shown that upon excitation with short flash groups a certain electric potential difference required before ATP can be synthesized. Moreover it is confirmed that the ATP-synthesis accompanied by an additional flux of protons down their electrochemical potential gradient. Correlation between the number of protons which have flowed across the ATPase coupled pathway, and the number of ATP-molecules which have been formed, yields a ratio H+/ATP = 3. Since this ratio includes only those protons, which have interacted with the ATPase complex, it represents the lower limit for H+/ATP-ratios determined by any other method. The necessity of a certain electric potential difference and the fact that 3 H+ have to be translocated down their electrochemical potential difference before one molecule of ATP can be synthesized is consistent with the chemiosmotic postulate, that the ADP ~ P bond energy derived from the electrochemical potential difference of the proton across the coupling membrane. With respect to the alternative hypothesis for phosphorylation, the results impose grave restriction on a phosphorylation driven only by the free energy of a chemical intermediate, if this does exist at all. [ABSTRACT FROM AUTHOR]

This article presents information on a previously published clinical study which focuses on the role of cerebrospinal fluid (CSF) protein in syphilis. The first object of the study was to discover the most accurate and reliable method of estimating the CSF protein. The Izikowitz method seemed highly efficient and correlated well with results obtained by paper electrophoresis, but it was found that the "globulin " fraction consisted mainly of gamma globulin, while the "albumen " fraction consisted of albumen and alpha and gamma globulins. The second object was to discover a "protein pattern" for cases of syphilis.

The article discusses a study on levels of copper in dental amalgams. The American Dental Association (ADA) standards for dental amalgams limit copper concentration to six percent. However, it was found that high concentrations of copper eliminated the γ2 phase, which is weak and electrochemically active.

Application of the potentiostatic polarization technique to the metallographic etching of set dental amalgam is described. Etching studies of amalgam prepared from a lathecut, a spherical, and a silver-copper dispersed-phase amalgam alloy are reported. The γ2 phase in set dental amalgam can be characterized by this electrochemical technique. [ABSTRACT FROM AUTHOR]

Vesicles of erythrocyte ghosts were produced by treatment with Primaquine or hexokinase. The resulting vesicles could be separated from each other and characterized by preparative free-flow electrophoresis. One population consisted of outside-out vesicles carrying the same sialic acid distribution as the original ghosts. The other represented homogeneous inside-out particles with a different electrophorctic mobility carrying most of their sialic acid at their inner side. The two kinds of vesicles could not be separated by density gradient centrifugation. [ABSTRACT FROM AUTHOR]

The article presents an abstract of the paper "Study of Electrophoresis in 13 Cases of Psoriasis," by M. Bolgert, J. Blamoutier and M. Moret. It opines that no characteristic electrophoretic variation was found in the blood in psoriasis.

This communication describes the use of micro-electrophoresis in studying the changes in ascites tumour cells exposed to antibodies and complement. Treatment of the cells with rabbit antibody led to a change in electrophoretic mobility consistent with a surface adsorption of γ-globulin. The addition of complement led to a reduction in this electrophoretic effect of antibody. Treatment of the cells with neuraminidase, which produced a marked fall in their electrophoretic mobility, did not alter the effect of rabbit antibody and complement on the cells. Incubation with iso-antibody, in the presence or absence of complement, did not alter the mobility of the ascites cells measured at pH 7.0. The addition of 0.01 M calcium chloride to the electrophoresis medium produced a fall in mobility of the cells exposed to either antibody preparation in the presence of complement. Therefore, although iso-antibody and complement did not produce direct changes in cell mobility, changes in the cell surface could be detected by electrophoresis in the presence of calcium ions. The possibility is discussed that, during immune cytolysis, unmasking of phosphate groups of phospholipids might take place in the cell surface. [ABSTRACT FROM AUTHOR]

New methods are presented for the isolation of nucleoli and the extraction of intact preribosomes under mild conditions avoiding EDTA and high salt buffers. These nucleolar preribosomes were characterized by an improved technique of polyacrylamide-gel electrophoresis which loves better resolution than sedimentation analysis for both ribonucleoprotein particles anti free-RNA molecules. Thus, the 50-S native-ribosomal subunit could be separated from its 55-S precursor containing 32-S pre-RNA, and another nucleolar precursor, a "70-S" particle, could be identified. The separation technique newly developed is disc electrophoresis using exponential polyacry1amide gels. The resolution with these gels is gloater than that with uniform gels over a wider range of molecular weights. The final resolution is independent of the volume in which the sample is loaded and the diffusion of molecules during migration is eliminated. Molecular weights of RNA molecules can be estimated in exponential gels as in uniform gels. Electrophoresis in quartz tubes allows the direct scanning of ultraviolet, absorbance during and after the run. As all handling is thus avoided, gels of very low concentration can be used. [ABSTRACT FROM AUTHOR]

All 21 ribosomal proteins from 30 S subunits of Escherichia coli were isolated in a pure state by the following methods: separation of subunits by zonal centrifugation in B XV rotors, extraction of proteins, CM-cellulose chromatography with pyridine formate gradients, gel filtration on Sephadex G-100 and, in some cases, preparative polyacrylamide block electrophoresis. The purity of isolated proteins was 97-100% shown by disc electrophoresis at pH 4.5 in urea, by two-dimensional polyacrylamide electrophoresis, by dodecylsulfate gel electrophoresis and by cellulose acetate gel electrophoresis. The yield of the isolated proteins was 7-110 mg depending on the protein and the number of purification steps. Fractionation of total 30 S proteins with ammonium sulfate is recommended for quick isolation of proteins S15 and S20 in large quantities. [ABSTRACT FROM AUTHOR]

The article refers to a study on the industrial chemistry courses. The plight of science graduates, majors in chemistry is pitiful. More than half of them are unemployed and the credit goes to the prevailing exclusion of detailed chemical courses. Chemistry has contributed towards the advancement of several industries. The industries in which chemistry has contributed are of abrasives, alcohol and other solvents, coke and its products, cotton and cotton products, the electrical industry, electrochemistry, glass and iron and steel manufacturing. There are some specialized industry chemistry courses which help the student to get acquainted with descriptive phase of a chemical industry. These industries are of paints, varnishes and lacquers, rayons, liquors. It is important for the student to consider a few points before selecting the industry. The stability, importance, demand of skilled men, cost of re-equipping are some points to be considered.

The activity of glutamate dehydrogenase( L-glutamate: NAD oxidoreductase, EC 1.4.1.2.; GDH) of rice plants changes in response to the nitrogen source supplied to the culture solution. The activity of NADH-GDH(aminating) in roots is rapidly increased by the addition of ammonia, whereas the activity in shoots is much less affected by nitrogen supply. The activity increased with increasing concentration of ammonia at least up to 14.3 mM. In roots GDH activity was found in both the mitochondrial and soluble fractions. The increase occurs in the latter fraction. The new band with GDH activity was detected on the zymogram of polyacrylamide gel electrophoresis and this inducible enzyme is active with both NAD and NADP. On the other hand, the constitutive enzyme activity active with NAD is also increased by the ammonia treatment. The increase if enzyme activity is prevented by the addition of cycloheximide or chloramphenicol to culture medium. The incorporation of 14C-leucine(U) into GDH proteins was also studied using polyacrylamide gel electrophoresis. Higher radioactivity was found in induced samples than in non‐induced ones. These results show that the increase of GDH activity in roots by ammonia treatment seems to depend on de novo protein synthesis. [ABSTRACT FROM AUTHOR]

Succinylated derivatives of bovine chymotrypsinogen A and α-chymotrypsin were prepared by treatment of the native proteins with succinic anhydride; 60% of the 6-amino groups of the 13 lysine residues form stable succinylated products. The large negative charge at neutral pH is reflected in electrophoretic and titration behavior but absorption spectra, rotatory-dispersion spectra and reversible unfolding behavior indicate that the succinylated species are conformationally similar to the parent proteins. Succinylated chymotrypsin is active as an esterase with N-acetyl-L-tryptophan ethyl ester with a small decrease in the maximum-velocity parameter. The pH dependence suggests that three ionizing groups influence catalytic behavior. The apparent pKa values analyzed in terms of three groups are shifted relative to α-chymotrypsin. Thermal-unfolding studies of succinylated chymotrypsinogen demonstrate the presence of substrates near pH 7 but is consistent with two-state behavior at other pH values. [ABSTRACT FROM AUTHOR]

A new hemoglobin variant, designated hemoglobin-St Luke's. was detected by routine starch-gel electrophoresis in four members of a Maltese family. The carriers of this abnormality are clinically and hematologically normal. Structural analyses showed the replacement of prolyl residue in position 95 (G2) of the alpha chain by an arginyl residue. The relative amount of hemoglobin-St Luke's present in the red cell hemolysates of its cagier is approximately 10 %, compared to about 23 % for hemoglobin-G Georgia and 15% for hemoglobin Rampa (the other two variant in which prolyl residue α95 (G2) is replaced). Sedimentation velocity studies of hemoglobin. St Luke's in NaCl solutions of increasing concentration up to 2 M indicate that the oxy derivative is extensively dissociated into dimers in 0.1 M NaCl at neutral pH; whereas under the same conditions, the deoxygenated molecule retains a tetrameric structure. In the deoxy state, appreciable tetramer formation occurs even in 2 M NaCl. In addition, association-dissociation in oxyor cyanferrihemoglobin St Luke's is troth pH and temperature dependent. [ABSTRACT FROM AUTHOR]