Total visitors: 1,621 since 15-06-05
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ISSN : 0301-1208 |
CODEN : IJBBBQ |
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VOLUME 42 |
NUMBER 3 |
JUNE 2005 |
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Papers |
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Fractal
studies on the protein secondary structure elements |
141 |
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Stage-specific
cytosolic protein kinase C-like activity in human malarial parasite Plasmodium falciparum |
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RNase and DNase activities of antiviral proteins from leaves of Bougainvillea xbuttiana |
152 |
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Purification and partial characterization of α-D-mannosidase from Erythrina indica seeds |
156
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Embryo
is not required for initiation of a-amylase activity in
germinating cowpea |
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β-Aminobutyric
acid-mediated enhancement of resistance in tobacco against TMV and
consideration of its capability in wounded tobacco plants |
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Shaolin Ge, Xinsheng
Cheng*, Zechun Xue, Liwen Yang and Xiaoyun Zheng |
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Phytomitogen induced
changes in levels of inositol phosphates in the bovine lymphocytes |
173
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Jyotsna Behl nee Dhingra*, N K Verma, Rahul Behl, S K Prasad and S P
S Ahlawat |
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Notes |
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Extracellular
enzyme production by environmental strains of Serratia spp. isolated from river Narmada |
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Characterization
and purification of alkaline phosphatase from Elephas trogontherii (Steppe elephant) bone |
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Determination
of serum lactate with alkylamine glass bound lactate oxidase |
186
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(Contd)
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Oxidative stress in
relation to lipid profiles in different stages of breast cancer |
190 |
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Aymelek Gönenç*, Devrim Tokgöz, Sabahattin Aslan
and Meral Torun |
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Indian Journal of Biochemistry &
Biophysics
Vol. 42, June 2005, pp. 141-144
Fractal
studies on the protein secondary structure elements
Y Surya Pavan and C K Mitra*
Received 1 December 2004; revised 2 May 2005
The fractal dimensions of the protein secondary structure elements based on the positional distributions were calculated. The seven secondary structure elements could be grouped into two distinct classes based on their fractal dimensions. A negative correlation was observed between the dimensional values of the secondary structures and their abundances. Markov model was applied, to check the persistence of transitions of the secondary structure elements, in the protein sequences. The results suggest the presence of long-range correlations in the protein sequences that may be useful in prediction algorithms.
Keywords: Fractal dimension, protein secondary structure elements, protein sequence, negative correlation, Markov model
Indian Journal of Biochemistry &
Biophysics
Vol. 42, June 2005, pp. 145-151
Stage-specific
cytosolic protein kinase C-like activity in human malarial parasite Plasmodium falciparum
Arun Sharma* and Sukla Biswas
Received 25 June 2004; revised 14 March 2005
Protein kinase C (PKC)-like activity was characterized in malarial parasite Plasmodium falciparum and its involvement in growth, maturation and differentiation functions, during the asexual stages (ring, trophozoite and schizont) of development was studied. PKC-like activity was found distributed in all the stages of the parasite maturation. The activity was predominantly cytosolic, however it was also present in the membrane fraction. The activation of cytosolic PKC required Ca2+, phosphatidyl serine (PS), and either diacylglycerol or phorbol myristate acetate (PMA). The 9-fold increase in the activity was observed in the presence of the co-factors (Ca2+, PS and PMA) in the late trophozoite stage, as compared to the ring stage. The activation of trophozoites with PMA resulted in redistribution of PKC-like activity from cytosol to membrane fractions. An antimalarial drug, chloroquine (CQ) inhibited directly the PKC-like activity in a dose-dependent manner (IC50 of 45 nM) in trophozoites of chloroquine-sensitive CQ(S) strains, however, the activity remained unaltered in the chloroquine-resistant CQ(R) strains. Kinetic studies showed that the inhibition of cytosolic PKC-like activity by CQ was non-competitive with respect to ATP, histone and PS. The results suggest that the PKC-like activity is developmentally expressed during the parasitic survival and development.
Keywords: Malaria, Plasmodium falciparum, protein kinase C, cytosol, membrane, drug resistance, chloroquine, phorbol myristate acetate, phosphatidyl serine, schizont, trophozoite
Indian Journal of Biochemistry & Biophysics
Vol. 42, June 2005, pp. 152-155
RNase and
DNase activities of antiviral proteins from leaves of Bougainvillea xbuttiana†
Shikha Bhatia and M L Lodha*
Received 4 October 2004;
revised 28 February 2005
Antiviral proteins (AVPs) purified from the leaves of Bougainvillea xbuttiana cv Mahara exhibited RNase activity against viral RNA of the tobamoviruses, Tobacco mosaic virus (TMV) and Sunnhemp rosette virus (SRV). They caused complete degradation of viral RNAs in a concentration-dependent manner. RNase activity gel assay ruled out the possibility of the presence of contaminating nucleases. AVPs also showed DNase activity, as indicated by conversion of supercoiled form of plasmid DNA into relaxed and linear forms. The implications of these activities in controlling plant viruses are discussed.
Keywords: Bougainvillea xbuttiana, antiviral proteins, ribosome inactivating proteins, DNase activity, RNase activity
Indian Journal of Biochemistry &
Biophysics
Vol. 42, June 2005, pp. 156-160
Purification
and partial characterization of α-D-mannosidase from Erythrina indica seeds
Rakesh M Kestwal and Shobhana V Bhide*
Received 13 September 2004; revised 14 March 2005
α-D-Mannosidase (EC: 3.2.1.24), a glycoprotein with 8.6% carbohydrate was purified (26 fold purification) to homogeneity from Erythrina indica seeds, by gel filtration on Bio-Gel P-100 and affinity chromatography on Con-A CL Seralose. The enzyme had the molecular mass of 124 kDa and 127 kDa by gel filtration and SDS-PAGE, respectively. The optimum pH and temperature for enzyme activity were found to be 4.6 and 50°C, respectively. The Km value for the enzyme was 2.1 mM for p-nitrophenyl-α-D-mannopyranoside. The enzyme activity was found to depend on the presence of Zn2+. Chemical modification studies revealed the involvement of tryptophan, serine and cysteine for enzyme activity.
Keywords: Erythrina indica, α-D-mannosidase, purification, con-A CL seralose, zinc
Indian Journal of Biochemistry &
Biophysics
Vol. 42, June 2005, pp. 161-165
Embryo is not required for initiation of a-amylase activity in
germinating cowpea (Vigna unguiculata
L.) seeds
Prabhdeep Kaur, Anil K Gupta and Narinder Kaur*
Received 18 October 2004; revised 8 April 2005
When embryonated and de-embryonated cotyledons of cowpea (Vigna unguiculata L.) were kept for germination, only embryonated cotyledons (EC) developed into seedlings. a-Amylase activity appeared late in de-embryonated cotyledons (DEC), but increased and matched with that of EC on 4th day, and thereafter started declining. A higher content of reducing sugars may be one of the factors in down regulating the activity in DEC after 4th day, in comparison to EC, where it continued increasing. Addition of GA3 to DEC did not increase the activity significantly, suggesting that GA3 was not a limiting factor for amylase initiation. Addition of 1 mM chlorocholine chloride (CCC) to DEC decreased activity by about 50%, suggesting that GA3 might partly be synthesized in the DEC and hence the activity could be initiated independent of embryo. However, for mobilization of starch, amylase activity has to be sustained for a longer period, for which sink strength in the form of shoot and root is essential. Unlike cereals, where embryo is required for induction of amylase, the process of amylase induction in germinating cowpea seeds appear to be different. Purification of a-amylase from EC and DEC by DEAE-cellulose and Sephadex G-150 column chromatography revealed three peaks in EC, and only one in DEC, indicating that gibberellin present in DEC could induce only one form of amylase. Amylase from DEC had higher Km value (0.33 mg ml-1 of starch), as compared to the corresponding Km value in EC (0.11 to 0.16).
Keywords: Cowpea, Vigna unguiculata, cotyledons, a-amylase, gibberellic acid,
embryonic axis
Indian Journal of Biochemistry &
Biophysics
Vol. 42, June 2005, pp. 166-172
β-Aminobutyric
acid-mediated enhancement of resistance in tobacco against TMV and
consideration of its capability in wounded tobacco plants
Shaolin Ge, Xinsheng Cheng*, Zechun Xue, Liwen Yang and Xiaoyun Zheng
Received 30 November 2004; revised 9 May 2005
Systemic acquired resistance (SAR) is an important component of disease-resistance arsenal of plants, and is associated with enhanced potency of activating local and systemic defense-related responses upon pathogen attack. In this report, we demonstrated that pre-treatment with β-aminobutyric acid (BABA), a new elicitor of SAR in the plants, enhanced resistance against tobacco mosaic virus (TMV) in a temperately-sensitive tobacco (Nicotiana tabacum L.) cultivar Yunyan 85. The resistance is based on the elicitation of defense-related responses induced by BABA that brings the TMV-susceptible tobacco plants to a defense-ready state, even before exposure to the pathogen. The induced resistance was strongly associated with potentiated activation of defense-related enzymes [phenylalanine ammonia lyase (PAL) and polyphenol oxidase (PPO)] activities, proportional to the concentration of the BABA sprayed. Interestingly, simultaneous clipping, an important agricultural practice in tobacco production, attenuated BABA-mediated enhancement of TMV resistance in tobacco. The changes in the defense-related enzymes activities indicated that the interaction between BABA and wounding was reciprocally antagonistic. Moreover, such a negative interaction regulated the expression of defense-related enzymes, depending on the time of induction.
Keywords: β-Aminobutyric acid
(BABA), tobacco, Nicotiana tabacum L., defense-related responses, systemic
acquired resistance, tobacco, TMV, wounding, defense-related enzymes
Indian Journal of Biochemistry &
Biophysics
Vol. 42, June 2005, pp. 173-177
Phytomitogen induced changes in levels of inositol phosphates in the
bovine lymphocytes
Jyotsna Behl nee Dhingra*, N K Verma, Rahul Behl, S K Prasad and S P S Ahlawat
Received 26 May 2004; revised 27 April 2005
The changes in levels of inositol phosphates and phosphoinositides were studied in the bovine lymphocytes, in response to phytomitogens (lectins)-concanavalinA (conA) and phytohaemagglutinin (PHA). Addition of conA and PHA resulted in a rapid increase in the cpm of total inositol phosphates (from 8599 ± 100 cpm/2 ´ 106 cells to 11228 ± 126 cpm/2 ´106 and 9758 ± 100 cpm/2 ´106 cells, respectively) at 1 min after mitogen stimulation. There was a concomitant decrease in the phosphatidylinositol levels at 1 min, which continued up to 5 min. At 1 min of stimulation, inositol diphosphate fraction exhibited maximum increase, as compared to inositol mono- and triphosphates, suggesting that it contributed the most towards the overall increase in the total inositol phosphates levels. Results suggest that bovine lymphocytes respond to phytomitogens with a rapid turnover of phosphoinositides.
Keywords: Inositol phosphates, phosphatidyl inositols
Indian Journal of Biochemistry &
Biophysics
Vol. 42, June 2005, pp. 178-181
Extracellular
enzyme production by environmental strains of Serratia spp. isolated from river Narmada
Anjana Sharma* and Richa Tiwari
Received 13 October 2004; revised 21 February
2005
Serratia a gram-negative enteric bacterium is generally recovered from clinical samples as an opportunistic human pathogen and rarely from water and soil. The extracellular enzymes produced by pathogen add to its virulence. In the present study, the extracellular enzymes secretion by 26 environmental strains of Serratia spp., isolated from different stations of river Narmada was investigated. Majority of isolates were capable of producing extracellular enzymes i.e., amylase, protease, lipase and chitinase, suggesting that they can be exploited as biocontrol and biodegrading agents. All the isolates, except S. fonticola were found to be potent protease producers, while only five isolates of S. marcescens produced chitinase.
Keywords: Serratia, extracellular enzymes, protease, chitinase, lipase, amylase.
Indian Journal of Biochemistry &
Biophysics
Vol. 42, June 2005, pp. 182-185
Characterization and
purification of alkaline phosphatase from Elephas
trogontherii (Steppe elephant) bone
Yaşar Demir, Safinur Yildirim and Nazan Demir*
Received 9 December 2004; revised 25 April 2005
Four isozymes of alkaline phosphatase (AP) were purified from Elephas trogontherii (Steppe elephant) from different locations in the bone (outer and inner peripheral, cytosolic, and integral) using Sephadex G-200 gel filtration and TEAE-cellulose anion-exchange chromatography. The specimen was obtained from Erzurum Museum and its age was approx. 0.3-0.5 million years old. No fungi or bacteria were present in the bone sample. The enzyme activity was determined by using p-nitrophenylphosphate as a substrate. SDS-PAGE of all the isozymes gave a single band at the same location. The molecular mass of the four isozymes as determined by using gel filtration was about 60 kDa. Optimum pHs for the four isozymes were between 8-8.5. The optimum temperatures of the isozymes were: outer peripheral, 37.5°C, cytosolic, 37.5°C, inner peripheral, 35°C and integral, 40°C. The values of Vmax and Km, as well different optimum temperatures indicated that isozymes were structurally different.
Keywords: Elephas trogontherii, elephant, bone, alkaline phosphatase.
Indian Journal of Biochemistry &
Biophysics
Vol. 42, June 2005, pp. 186-189
Determination of serum lactate with alkylamine glass bound lactate
oxidase
Suman and C S Pundir*
Received 14 July 2004; revised 7 March 2005
Commercial lactate oxidase (Lactate:O2; oxidoreductase EC 1.1.3.2) from Pediococcus species was immobilized on to alkylamine glass beads (pore diameter 55 nm) through glutaraldehyde coupling with a conjugation yield of 3.2 mg/g support and 105% retention of initial activity. Immobilized enzyme showed maximum activity at pH 6.5, when incubated at 40°C for 12 min and was used for determination of lactic acid in serum. The H2O2 generated from serum lactate by immobilized enzyme was measured colorimetrically at 565 nm by its oxidative coupling with 4-aminoantipyrine and N,N¢-dimethyaniline catalyzed by horseradish peroxidase. A linear relationship was observed between A565 and lactic acid concentration ranging from 0.075 mM to10 mM. The minimum detection limit of the method was0.075 mM, which was better than that of enzymic colorimetric method employing free enzyme (0.2 mM). Within day andbetween day coefficient of variations were <8.0% and <19%,respec-tively. Serum lactic acid values determined by the present method were in good correlation (r = 0.99) with the currently used enzymic colorimetric method. The cost of lactate determination for 100 serum samples was less, as compared with Sigma kit method.
Keywords: Lactate, lactate oxidase, immobilization, alkylamine glass, serum, lactic acid determination
Indian Journal of Biochemistry &
Biophysics
Vol. 42, June 2005, pp. 191-194
Oxidative stress in relation to lipid profiles in different stages of
breast cancer
Aymelek Gönenç*, Devrim Tokgöz, Sabahattin Aslan and
Meral Torun
Received 10 November 2004; revised 4 May 2005
The changes in the levels of MDA, nitrite, vit. E, lipids (total cholesterol and triglycerides) and lipoproteins (HDL and LDL cholesterol) were estimated among breast cancer patients, in relation to different clinical stages (stage I to IV). MDA and nitrite levels were increased in breast cancer patients, irrespective of clinical stage, as compared to controls (p<0.01). Their levels were also significantly elevated from stage III to stage IV (p<0.05). In contrast, vit. E levels were decreased in all stages, as compared to control group (p<0.05), the decrease was more pronounced in stage II and IV. Compared to controls, serum triglycerides were elevated in all patient groups (p<0.05); the maximum increase was in stage IV. HDL-cholesterol decreased in all stages, when compared with control group (p<0.05). These findings support the hypothesis that reactive oxygen and nitrogen species are increased in breast cancer, especially metastases and may cause consumption of vit. E.
Keywords: Malondialdehyde; vitamin E;
nitrite; cholesterol; high-density lipoprotein; low-density lipoprotein;
triglycerides; breast cancer, oxidative stress