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1.
Vasant Gurunath Rao 《Mycopathologia》1970,42(3-4):241-258
The paper deals with some of the contributions made from India by various research workers towards our knowledge of the fungus genusPhytophthora de Bary, in the fields of morphology, disease production, occurrence and distribution of species, host range, physiology, taxonomy and control measures. Out of the total of fifteen species and five varieties ofPhytophthora reported from India, five species (viz.,P. arecae, P. palmivora, P. colocasiae, P. parasitica andP. infestans, and four varieties ofP. parasitica, viz.,P. parasitica var.macrospora, var.sesami, var.piperina and var.nicotianae) assume considerable parasitic roles inciting serious diseases like seedling-blights, wilts, cottoney-leaks, foot-rots, blights, budrot and rots of fruits, nuts, tubers and corms etc. They are widely distributed in various parts of this country, and are mostly prevalent in rainy seasons.Phytophthora palmivora, andP. parasitica were found to have a wide host range. 相似文献
2.
Vasant Gurunath Rao M. Sc. 《Mycopathologia》1963,21(1):45-59
Summary Of the 20 species ofPythium reported from India, not more than seven assume parasitic role inciting mainly diseases in seed bed and sometimes in the fields such as damping-off, seedling blights and foot rots. The paper gives a brief account of the taxonomy of the Indian species and methods of controlling the diseases incited by them. 相似文献
3.
Garima Tripathi Anima Tripathi Gurunath Ramanathan Shail K. Chaube 《International journal of peptide research and therapeutics》2016,22(1):57-66
The study was designed to investigate whether crown ether containing dipeptide Boc-12-crown-4-l-DOPA-Gly-OMe has potential to induce meiotic cell cycle arrest and apoptosis in rat eggs cultured in vitro. The immature female rats were subjected to superovulation induction protocol and ovulated eggs were collected from ampulla of the fallopian tube. Ovulated eggs arrested at metaphase-II (M-II) stage of meiotic cell cycle were cultured in media-199 with or without various concentrations (0.0, 0.025, 0.050, 0.10, and 0.20 mM) of dipeptide for 3 h in vitro. Morphological apoptotic changes, hydrogen peroxide (H2O2) concentration, cytochrome c level, caspase-3 level as well as activity and DNA fragmentation were analysed in eggs cultured in vitro. Culture of M-II arrested eggs in plain medium for 3 h in vitro induced meiotic exit from M-II arrest in majority of eggs as evidenced by initiation of extrusion of second polar body (II PB). The dipeptide induced maintenance of M-II arrest and morphological apoptotic features in a concentration-dependent manner prior to degeneration. The dipeptide-induced morphological features were associated with increased H2O2 and cytochrome c levels in treated eggs. The increased cytochrome c induced caspase-3 level and activity and thereby DNA fragmentation as evidenced by DAB positive staining in treated eggs. Our results suggest that dipeptide Boc-12-C-4-l-DOPA-Gly-OMe induces cell cycle arrest at M-II stage and apoptosis in rat eggs cultured in vitro. 相似文献
4.
Deepak Singh Archana Kumari S. Ramaswamy Gurunath Ramanathan 《Biochemical and biophysical research communications》2014
3-Nitotoluene dioxygenase (3-NTDO) is the first enzyme in the degradation pathway of 3-nitrotoluene (3-NT) by Diaphorobacter sp. strain DS2. The complete gene sequences of 3-NTDO were PCR amplified from genomic DNA of Diaphorobacter sp., cloned, sequenced and expressed. The 3-NTDO gene revealed a multi component structure having a reductase, a ferredoxin and two oxygenase subunits. Clones expressing the different subunits were constructed in pET21a expression vector system and overexpressed in E. coli BL21(DE3) host. Each subunit was individually purified separately to homogeneity. The active recombinant enzyme was reconstituted in vitro by mixing all three purified subunits. The reconstituted recombinant enzyme could catalyse biotransformations on a variety of organic aromatics. 相似文献
5.
In the title family, the ONO donor ligands are the acetylhydrazones of salicylaldehyde (H2L1) and 2-hydroxyacetophenone (H2L2) (general abbreviation, H2L). The reaction of bis(acetylacetonato)oxovanadium(IV) with a mixture of tridentate H2L and a bidentate NN donor [e.g., 2,2′-bipyridine(bpy) or 1,10-phenanthroline(phen), hereafter B] ligands in equimolar ratio afforded the tetravalent complexes of the type [VIVO(L)(B)]; complexes (1)-(4) whereas, if B is replaced by 8-hydroxyquinoline(Hhq) (which is a bidentate ON donor ligand), the above reaction mixture yielded the pentavalent complexes of the type [VVO(L)(hq)]; complexes (5) and (6). Aerial oxygen is most likely the oxidant (for the oxidation of VIV → VV) in the synthesis of pentavalent complexes (5) and (6). [VIVO(L)(B)] complexes are one electron paramagnetic and display axial EPR spectra, while the [VVO(L)(hq)] complexes are diamagnetic. The X-ray structure of [VVO(L2)(hq)] (6) indicates that H2L2 ligand is bonded with the vanadium meridionally in a tridentate dinegative fashion through its phenolic-O, enolic-O and imine-N atoms. The general bond length order is: oxo < phenolato < enolato. The V-O (enolato) bond is longer than V-O (phenolato) bond by ∼0.07 Å and is identical with V-O (carboxylate) bond. 1H NMR spectrum of (6) in CDCl3 solution indicates that the binding nature in the solid state is also retained in solution. Complexes (1)-(4) display two ligand-field transitions in the visible region near 820 and 480 nm in DMF solution and exhibit irreversible oxidation peak near +0.60 V versus SCE in DMSO solution, while complexes (5) and (6) exhibit only LMCT band near 535 nm and display quasi-reversible one electron reduction peak near −0.10 V versus SCE in CH2Cl2 solution. The VO3+-VO2+E1/2 values shift considerably to more negative values when neutral NN donor is replaced by anionic ON donor species and it also provides better VO3+ binding via phenolato oxygen. For a given bidentate ligand, E1/2 increases in the order: (L2)2− < (L1)2−. 相似文献
6.
A bacterial strain, PNS-1, isolated from activated sludge, could utilize sulphanilic acid (4-ABS) as the sole organic carbon and energy source under aerobic conditions. Determination and comparison of 16S r DNA sequences showed that the strain PNS-1 is closely related to the species of Agrobacterium genus. Growth on 4-ABS was accompanied with ammonia and sulfate release. TOC results showed complete mineralization of sulphanilic acid. This strain was highly specific for 4-ABS as none of the sulphonated aromatics used in the present study including other ABS isomers were utilized. Strain PNS-1 could, however, utilize all the tested monocyclic aromatic compounds devoid of a sulfonate group. No intermediates could be detected either in the growth phase or with dense cell suspensions. Presence of chloramphenicol completely inhibited 4-ABS degradation by cells pregrown on succinate, indicating that degradation enzymes are inducible. No plasmid could be detected in the Agrobacterium sp. Strain PNS-1 suggesting that 4-ABS degradative genes may be chromosomal encoded. 相似文献
7.
Pregnane glycosides from Caralluma adscendens var. fimbriata 总被引:1,自引:0,他引:1
Kunert O Rao VG Babu GS Sujatha P Sivagamy M Anuradha S Rao BV Kumar BR Alex RM Schühly W Kühnelt D Rao GV Rao AV 《化学与生物多样性》2008,5(2):239-250
Eleven novel pregnane glycosides, 2-7 and 9-13, of which four, i.e., 10-13, comprised a new pregnane-type genin exhibiting a hydroxymethylene instead of a Me group at C(19), and the known pregnane glycoside stalagmoside V (8) were isolated from whole plants of Caralluma adscendens var. fimbriata, a native Indian succulent plant. Their structures were elucidated by extensive 2D-NMR spectroscopic studies. 相似文献
8.
Vasant Gurunath Rao 《Mycopathologia》1970,42(1-2):39-48
The paper deals with the influence of temperature on the growth and sporulation of two species ofPhytophthora, viz.,P. palmivora
Butl. andP. parasitica
Dast. var.macrospora
Ashby, the causal agents of fruit rots ofAchras sapota L. andAnona squamosa L. respectively. Germination of sporangia at different temperatures were also undertaken. There was marked variation in growth and sporulation of these two organisms. Isolate C (Phytophthora palmivora) showed no growth at 5° and 35°C, scanty growth at 10° and 32.5° with an optimum temperature between 26–28°C. On the other hand, Isolate S (Phytophthora parasitica var.macroscora) showed no growth at 10°C, but slight growth even at 37°C. Eight days exposure at 37°C completely stopped the growth of this Isolate. It showed best growth at 30°C and hence this was its optimum temperature. In general, Isolate C sporulated abundantly at all temperatures tested but reached its maximum at 25°C. On the other hand Isolate S showed best growth but failed to sporulate at any of the temperatures in 98 hours growth, although it sporulated freely when the incubation period extended up to two weeks. On the basis of temperature toleration the twoPhytophthora isolates are distinguished from each other as two different species. This confirms the earlier observations and nomenclature criterion as emphasized and formulated byTucker (1931). In the germination studies, it was observed that the indirect germination with the formation of abundant zoospores started from 5° and continued even up to 35°C, reaching maximum at 20°C. High temperature was not favourable for indirect germination. As the temperature proceeded increasing, the percentage of direct germination by formation of germ tubes also increased. Direct germination was observed from 10° which continued up to 37°C, with a maximum reach at 30°C. This confirms the epidemic of fruit rots in nature during monsoon season which is prevalent with the persistence of high humidity and rainfall.Taken from a thesis submitted by the author for the degree of Master of Science in the Faculty of Agriculture, Poona University, India. 相似文献
9.
10.
Truncated thioredoxin (Trx80) exerts unique mitogenic cytokine effects via a mechanism independent of thiol oxido-reductase activity 总被引:3,自引:0,他引:3
Pekkari K Avila-Cariño J Gurunath R Bengtsson A Scheynius A Holmgren A 《FEBS letters》2003,539(1-3):143-148
Recently we discovered that a naturally occurring C-terminally truncated thioredoxin (Trx80) is a potent mitogenic cytokine stimulating IL-12 production from CD40(+) monocytes. To further characterise Trx80 we have engineered cysteine to serine mutants of Trx80 corresponding to the active site cysteines of Trx (Trx80SGPS) and to the structural cysteine at position 72 (Trx80C72S). Trx80SGPS and Trx80C72S retained the cell stimulatory activity of Trx80 and increased peripheral blood mononuclear cell (PBMC) proliferation three- to five-fold in vitro (P<0.01, n=18). Both Trx80SGPS and Trx80C72S significantly stimulated IL-12 and IFN-gamma secretion from PBMCs in the same manner as Trx80 (P<0.01, n=9 and 10). The previously described Trx80 dimer is caused by non-covalent interactions, and not by any intermolecular disulphide bonds. 相似文献