Journal of Biosciences

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Studies on plant gums. Role of calcium in polysaccharide-protein interaction in the neem (Azadirachta indica) gum.
(1979-03) Nayak, B Ramakrishna; Shenoy, B C; Pattabiraman, T N
The partial removal of tightly bound Ca2+ from dialysed neem (Azadirachta indica) gum, resulted in the release of a basic protein from a highly anionic polysaccharide-protein complex as evidenced by chromatographic studies on TEAEcellulose. Complete removal of Ca2+ caused, in addition, the release of a minor heteropolysaccharide which was found in association with the basic protein. These processes were reversed on the addition of Ca2+. The gum, in addition, contained a protein-rich component accounting for 35% protein and 7·5% total carbohydrate. This component behaved as a distinct entity during ion-exchange chromatography of the native gum solutions, or which were either partially or completely depleted of bound Ca2+.
Removal of radioactive strontium from the rat by feeding stable strontium.
(1979-03) Kshirsagar, S G
The effect of administering the stable isotope of strontium (as phosphate) at different dietary levels to adult rats (fed on a cereal and pulse-based diet containing 0·4% Ca) on the retention of radiostrontium (89Sr) and radiocalcium (45Ca) in the femur and the whole skeleton was studied for a period up to 6 weeks after an intraperitoneal injection of the two radioisotopes. The ability of strontium to remove 89Sr under the above dietary conditions was examined. Feeding Sr at 0·5% or 1% levels for 6 weeks had no effect on the skeletal content of 89Sr or 45Ca while a dietary regimen of 2% Sr (2000 times the normal content), significantly lowered the 89Sr and 45Ca content by about 30% in the femur but not in the whole skeleton. At this Sr level, the urinary excretion of the isotopes increased with a concomitant decrease in their excretion in the faeces. This study underscores the limitations of dietary Sr to mobilise 89Sr from the bones after it is incorporated in the bone mineral.
Distribution of acid and alkaline deoxyribonucleases in white and grey matter regions of growing and aging chick brain.
(1979-03) Rao, K Subba; Shrivastaw, K P
The activities of acid and alkaline deoxyribonucleases in the white and grey matter areas of growing and old chick cerebrum were measured. Two marker enzymes for glial cells, butyrylcholinesterase and carbonic anhydrase were also measured in these regions. Higher specific activities of both butyrylcholinesterase and carbonic anhydrase were found in the white matter region at all the stages studied. Acid and alkaline deoxyribonuclease activities were observed in both white and grey matter. The decrease in the specific activity of acid deoxyribonuclease with advancement of age was more pronounced as compared to the alkaline deoxyribonuclease Marked reduction in total acid deoxyribonuclease activity in white matter, beyond the age of 130 days, was observed. On the other hand, total alkaline deoxyribonuclease activity in both white and grey matter continued to increase with age Further, the activity per mg of DNA also increased in white matter of the old brain. These results indirectly suggest a continued role for alkaline deoxyribonuclease in glial cells formed at a later age.
Changes in carbohydrates and lipids during embryonic development of Antheraea mylitta (Lepidoptera).
(1979-03) Pant, Radha; Kumar, Suman; Singh, Shiva Dhar
Changes in carbohydrate and lipid metabolism during embryonic development in Antheraea mylitta were studied. While carbohydrates were metabolized during early embryogenesis, lipids were catabolised at the later stages. A significant increase in both total carbohydrates and glycogen on days 5 and 6 suggested the concurrent occurrence of both gluconeogenesis and glycogenesis. As the development of the embryo proceeds, both lipids and carbohydrates were utilised, resulting in the increase in the concentration of citrate, pyruvate and lactate.
Effect of phospholipase-D on rat kidney mitochondria.
(1979-03) Zaidi, S N A; Shipstone, A C; Garg, N K
Incubation of purified rat kidney mitochondrial fraction with phospholipase- D resulted in the accumulation of phosphatidic acid in the membrane due to the degradation of membrane-bound phosphatidylcholine, -serine and -ethanolamine Simultaneously with the hydrolysis of the phospholipids, cholesterol and protein were released from the mitochondrial membrane into the medium, and binding of Ca2+ by mitochondrial membranes increased. Phospholipase Dtreated mitochondrial fraction exhibited increased swelling in vitro in the early stages of incubation (15 min) after which the mitochondria were ruptured. Membrane- bound adenosine triphosphatase was partially inactivated and the enzyme activity was not significantly restored by incubation with sonicated dispersions of phosphatidylcholine, -serine and cholesterol. These results indicate that removal of choline, serine and ethanolamine from membrane-bound phospholipids disrupt phospholipid-cholesterol and phospholipid-protein association and affect functions of the membrane.
Studies on glutamine synthetase. Purification of the enzyme from mung bean (Phaseolus aureus) seedlings and modulation of the enzyme-antibody reaction by the substrates.
(1979-03) Seethalakshmi, S; Rao, N Appaji
Glutamine synthetase (L-glutamate : ammonia ligase, EC 6.3.1.2) from Phaseolus aureus (mung bean) seedlings was purified to homogeneity by ammonium sulphate fractionation, DEAE-cellulose chromatography, Sephadex G-200 gel filtration and affinity chromatography on histidine-Sepharose. The enzyme had a molecular weight of 775,000 ± 25,000. The enzyme consisted of identical subunits with an approximate subunit molecular weight of 50,000. Hyperbolic saturation curves were obtained with the substrates, glutamate, ATP and hydroxylamine. Antibody, raised in the rabbit, against mung bean glutamine synthetase, completely inhibited the activity of the enzyme. Preincubation of the enzyme with glutamate and ATP, prior to the addition of the antibody, partially protected the enzyme against inhibition. The Km values of this enzyme-antibody complex and the native enzyme were identical (glutamate, 2.5mM; ATP, 1 mM; hydroxylamine, 0·5 mM). The Km values of the partially inhibited enzyme (the enzyme pretreated with antibody prior to the addition of substrates) were 2-fold higher than those of the native enzyme. These results suggested that the substrate-induced conformational changes in the enzyme were responsible for the protection against inhibition of the enzyme activity by the antibody.
A rapid and gentle method for the salt extraction of chromatin core histones H2A, H2B, H3 and H4 from rat liver nuclei.
(1979-03) Jamaluddin, M; Philip, Mohanan; Chandra, H Sharat
A complex of histones H2A, H2B, H3 and H4 has been isolated from purified rat liver nuclei by a method which is both gentle and rapid. Nuclei were homogenised in 0·25 Μ sucrose and the residual nuclear material obtained after centrifligation was adsorbed on calcium phosphate gel. After removing histone H1 from the adsorbed material by washing with 1M NaCl in 25 mM sodium phos phate buffer, pH 6·0, histones H2A, H2B, H3 and H4 were eluted together, with 2 Μ NaCl in 25 mM sodium phosphate buffer, pH 7 · 0. The core histones so obtained migrated as a single sharp band on polyacrylamide gel electrophoresis under non denaturing conditions. Fractionation of the freshly prepared core histones on a Sephadex G 100 column yielded two major protein peaks. The peak having the larger elution volume contained histones H2A and H2B in equal amounts while the peak with the smaller elution volume contained all the four histones. Histones H3 and H4 were present in larger proportions in the second peak.
Inhibitory effect of penicillin on spore-specific functions in Bacillus polymyxa 2459.
(1979-03) Goel, Anil K; Jayaraman, Kunthala
Penicillin at concentrations non-inhibitory to the vegetative growth was found to inhibit sporulation in Bacillus polymyxa 2459. The effect of penicillin was shown to be at the level of spore-specific mucopeptide synthesis. Penicillin had no effect on the early events such as DNA and protein synthesis in sporogenesis The sensitive period of inhibition was between T0 to T2 hours of sporulation.
Alteration of the structure of the Escherichia coli ribosomes on treatment with Fab fragment of immunoglobulin raised against the ribosomes.
(1979-03) Das, M; Burma, D P
Rabbits were immunised against Escherichia coli ribosomes and the partially purified immunoglobulin G fraction had maximum ability to precipitate the ribosomes as well as the extracted ribosomal proteins. By digestion of immunoglobulin G with papain, monovalent Fab fragments were produced. The 70 S ribosome and its subunits (50 S and 30 S) were separately treated with Fab and then tested in the kinetic assay of degradation of ribosomes by ribonuclease I at various Mg2+ concentrations. Treated ribosomes and their subunits were degraded at faster rates than the nontreated ones; the rates in both the control and the treated cases were dependent on the concentration of Mg2+. These results indicate the unfolding of the structure of the ribosome on treatment with antibody fragments, which may be due to the weakening of the interaction between rRNAs and ribosomal proteins.
Metal binding to pyridoxal derivatives. An NMR study of the interaction of Eu(III) with pyridoxal phosphate and pyridoxamine phosphate.
(1979-03) Rao, B N Narasinga; Ramakrishnan, C; Balaram, P
The solution conformations of pyridoxal-5'-phosphate and pyridoxamine- 5'-phosphate have been investigated using Eu(III) as a nuclear magnetic resonance shift probe. Binding of Eu(III) to pyridoxal phosphate results in the formation of two complexes, at the phosphate group and the o-hydroxy-aldehyde moiety, which are in slow exchange on the nuclear magnetic resonance time-scale. The lanthanide-induced pseudo contact shifts calculated using the McConnell-Robertson equation (J. Chem. Soc. (1950), 22, 1561) are in good agreement with the experimentally observed values for both pyridoxal phosphate and pyridoxamine phosphate and lead to a family of closely related conformations.
Interaction of amino acids with glycyl-glycine transport in the mammalian intestine.
(1979-03) Ganapathy, V; Hellier, M D; Radhakrishnan, A N
In order to investigate a possible interaction between free amino acids and dipeptides during their mucosal uptake in man and monkey, perfusion studies in vivo and uptake studies in vitro using labelled and non-labelled dipeptides and amino acids have been carried out. In contrast to the observations of other workers, inhibition of glycyl-glycine uptake was observed with free leucine and methioninc but not with glycine, proline, hydroxyproline or alanine. Leucine and methionine caused inhibition of cytosol glycyl-glycine hydrolase activity, while glycine had no effect. The dipeptide uptake and dipeptide hydrolysis by cytosol enzyme was competitively inhibited by leucine. Although brush border glycyl-glycine hydrolase was also inhibited by leucine, the inhibition was noncompetitive. These data indicate that a few free amino acids can interact with dipeptides during uptake. This interaction might occur either at the transport step or at the stage of intracellular dipeptide hydrolysis.
Alpha-tocopheryl acetate hydrolase in chicken liver. Characterisation and properties.
(1979-06) Kartha, V N R; Bai, N Jayanthi; George, Thomas; Krishnamurthy, S
An enzyme catalysing the hydrolysis of a-tocopheryl acetate was characterised in chicken liver. The enzyme was localised in the microsomes, had an optimum pH 8·6 and a Km value of 0·5 mM. The enzyme did not hydrolyse retinyl acetate, cholesteryl acetate and ethyl acetate, thus indicating a high degree of specificity. a-Tocopheryl acetate hydrolase required bile salts as a specific cofactor. The results suggested a role for this enzyme in the absorption of vitamin E.
Reduction in population growth under different contraceptive Policies.
(1979-06) Singh, S N; Yadava, K N S
A number of equations for the various population control policies are worked out for a desired reduction in the rate of growth. At the ages of 25 and 30 respectively, 61 and 97% of contraceptive users are necessary to reduce the present rate of growth of 0·026 to 0·010. While at the age of 25 about 69 and 76% contraceptive users are required for the same reduction in the rate of growth, assuming that 25 and 50% would discontinue the use of contraceptives at the age of 35. The birth and death rates in the study area (Varanasi Rural) have remained almost constant for several years, justifying the assumption of a stable population. This study emphasises the need for the use of contraceptive devices at two or more age levels.
Species variation in the localisation of esterases in the cerebellar cortex of mouse and bat.
(1979-06) Sood, P P; Bohra, M H; Banu, Hafiza
A comparative study of the distribution of a simple esterase and acetylcholinesterase in the cerebellar cortex of mouse and bat has been made. The Purkinje layer is intensely positive for simple esterase in both species. The granular and molecular layers showed mild to moderate activity in mouse and intense activity in bat. Acetylcholinesterase in cerebellar layers of bat is more intense than in mouse. In bat cerebellum, acetylcholinesterase is observed in the dendrites of Purkinje cells, but not in their cell bodies. Acetylcholinesterase was not found in Purkinje cells of mouse.
Microbial transformation of isonicotinic acid hydrazide and isonicotinic acid by Sarcina sp.
(1979-06) Gupta, R C; Shukla, O P
Metabolism of isonicotinic acid and isoniazid by Sarcina sp. led to the formation of two metabolites which were characterised as 2-hydroxyisonicotinic acid and citrazinic acid. The blue pigment formed during fermentation was shown to be derived from the auto-oxidation of citrazinic acid. 2-Oxo-glutarate accumulated as the major keto acid when isonicotinic acid or isonicotinic acid hydrazide metabolism was inhibited by 1 mM sodium arsenite. Isonicotinic acid, 2-hydroxyisonicotinic acid and 2-oxo-glutarate were oxidised by isonicotinic acid hydrazide or isonicotinic acid-grown cells; citrazinic acid was, however, not oxidised. Isoniazid hydrazine hydrolase, isonicotinic acid and 2-hydroxyisonicotinic acid hydroxylases were detected in the cell-free extract of Sarcina sp. grown on isonicotinic acid hydrazide or isonicotinic acid.
An actinomycete producing L-3,4-dihydroxyphenylalanine from L-tyrosine.
(1979-06) Sukumaran, C P; Singh, D V; Khedkar, P D; Mahadevan, P R
An actinomycete was isolated during a soil screening programme to obtain L-3,4-dihydroxyphenylalanine producers. A mutant of this organism was isolated by chemical mutagenesis and it accumulated 1 g/litre L-dihydroxyphenylalanine when grown on L-tyrosine. Resting cells converted 30% of tyrosine in the reaction mixture. The use of resting cells for dihydroxyphenylalanine production is advantageous as it eliminates interfering substances which accumulate during fermentation.
Effect of cholesterol on multiplication, lipid metabolism and lysosomal enzymes of Hartmanella culbertsoni.
(1979-06) Lal, A A; Garg, N K
Addition of sonicated dispersions of cholesterol to peptone-salt-vitamin medium resulted in the metabolism of the sterol by Hartmanella culbertsoni. Trophozoite multiplication was stimulated at 1–5 mg/litre, but retarded at 10-20 mg/litre. When cholesterol was added to the medium, incorporation of [1,2—14C] –acetate into neutral lipid, phospholipid, non-saponifiable and cholesterol fractions of the amoebae was significantly reduced. Cholesterol ester was detected in the medium but phospholipids were not released. Addition of cholesterol stimulated the activity of lysosomal acid phosphatase, acid deoxyribonuclease and cathepsin Β but did not affect 5'-nucleotidase, adenosine triphosphatase, alkaline phosphatase, glucose-6-phosphatase, succinate dehydrogenase and cytochrome C oxidase.
Toxic and antigrowth effects of raw and processed field bean (Dolichos lablab) on albino rats.
(1979-06) Ramamani, S; Subramanian, N; Parpia, H A B
Samples of freeze dried green field bean (Dolichos lablab) and dry mature bean, were subjected to the following processing methods—heat processing, extraction with 80% ethanol, hexane or dilute acid, protein isolation; and these samples were evaluated for growth promoting value and toxicity. Extraction with 80% ethanol or with dilute acid increased survival period of the animals; but these did not promote growth. Heat processing was essential to destroy antinutritional factors and promote growth. Extraction of the beans with 80% ethanol did not however alter the trypsin inhibitor or haemagglutinin activities. The protein isolate and acid-extracted residue which had low trypsin inhibitor and haemagglutinin activities, did not also promote growth. Thus the trypsin inhibtor and haemagglutinin activities did not completely account for the toxicity to albino rats. However, heat processing of ethanol extracted bean flour indicated that the beneficial effect of ethanol extraction was not apparent, once the samples were heat processed. Dry mature bean dhal was more toxic than the whole bean either dry or green. Supplementation of heat processed field bean with methionine and tryptophan promoted good growth of albino rats and significantly increased the protein efficiency ratio.
Diamine oxidase of Lathyrus sativus seedlings. Purification and properties.
(1979-06) Suresh, M R; Adiga, P R
Diamine oxidase (EC 1.4.3.6) was purified from 5-day-old etiolated seedlings of Lathyrus sativus by MnCl2 treatment, (NH4)2SO4 and acetone fractionations, DEAE-Sephadex chromatography followed by gel filtration on Sephadex G-200. A single step purification of the enzyme was achieved by using an immunoaffinity column, wherein rabbit antibodies to the homogeneous diamine oxidase were coupled to CNBr-activated Sepharose. The enzyme thus obtained was homogeneous by electrophoretic, immunological and ultracentrifugal criteria. It had an Mr of 148,000 (6·46S) and was a dimer with similar sub-units (Mr 75,000). Amino acid analysis showed the absence of cysteine residues although it contained five disulphide bonds. The enzyme had copper (2·7 g atom/mol enzyme) but was not a glycoprotein. No absorption maximum in the visible region was detectable. Ethylenediamine 1,3-diaminopropane and histamine were potent competitive inhibitors for the substrate putrescine. The addition of monospecific antibodies to the enzyme increased the Km for benzyl amine without any change in the Vmax. Diamine oxidase from pea seedling, partially purified, exhibited complete crossreactivity with the antibodies to the L. sativus enzyme.
Light microscopic features of the rete testis, the vas efferens, the epididymis and the vas deferens in the adult rhesus monkey.
(1979-06) Prakash, Asha; Prasad, M R N; Kumar, T C Anand
The present study was carried out to determine the detailed histological and cytological features of the excurrent ducts of the male reproductive system in the rhesus monkey. The excurrent ducts show a regional difference in their histological features. The use of some of these features as histological markers and their possible functional significance are discussed. The epithelial cells in the different components of the excurrent duct system possess cytological features which suggest their involvement in absorption and the secretion of different products into the lumen.

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