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Streptomyces venezuelae P(10) could produce extracellular chitinase in a medium containing 0.6% colloidal chitin that was fermented for 96 hours at 30 degrees C. The enzyme was purified to apparent homogeneity with 80% saturation of ammonium sulfate as shown by chitin affinity chromatography and DEAE-cellulose anion-exchange chromatography. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) of the enzyme showed a molecular weight of 66 kDa. The chitinase was characterized, and antifungal activity was observed against phytopathogens. Also, the first 15 N-terminal amino-acid residues of the chitinase were determined. The chitin hydrolysed products were N-acetylglucosamine and N, N'-diacetylchitobiose.

Actual nitrogen fixation of root nodules of differentAlbizia-rhizobium symbioses, was compared with the potential nitrogen fixation of isolated bacteroids. The potential nitrogen fixation exceeded actual nitrogen fixation in all symbionts. After addition of nitrate the actual nitrogen fixation decreased more than did potential nitrogen fixation in effective symbiosis, whereas in a less effective symbiosis, the actual and potential nitrogen fixation increased as a result of better photosynthate supply to the roots and nodules. As confirmed by correlation analysis, the nitrogen fixation and photosynthetic yield of suboptimum symbioses were relatively enhanced by dressing with inorganic nitrogen fertilizer.

An attempt to transfer genes from droughttolerant Diplotaxis harra, a wild relative of Brassica species, to an elite oil-yielding cultivar, B-85, of mustard (Brassica juncea) was made through protoplast fusion, as the two plant systems are sexually incompatible. By following the standard protocol for PEG-mediated protoplast fusion followed by high pH, high Ca(++), DMSO treatment and appropriate cell-culture technique, 16 presumptive somatic hybrid plants could be regenerated. Chromosomal analysis of four such somatic hybrids revealed that three of them were asymmetric. Analysis of morphological characters, meiotic chromosomes, and esterase isoenzyme pattern revealed that all the somatic hybrids were different from each other. Furthermore four chromosomes of each genome could undergo homoeologous pairing at meiosis indicating the possibilities for genetic recombination and chromosomal rearrangements. Irregular distribution of chromosomes at anaphase-II at meiosis has been a consistent feature of these plants. Eventually, pollen of all the somatic hybrids showed complete infertility preventing the recovery of any selfed seed. Nevertheless, ovule fertility of one somatic hybrid was not totally impaired as it had set some seeds upon backcrossing with the B. juncea parent. The esterase isoenzyme banding pattern of 24 individual progeny plants of this backcross provided evidence for their recombinant nature. It was thus confirmed that a transfer of genetic traits from Diplotaxis harra to B. juncea had indeed taken place. Furthermore, it was conceptualised that a transfer of alien genes through the protoplast-fusion technique is primarily possible in situations where meiotic pairing of the chromosomes of the two participating genomes generates recombinant gametocytes which can pass through subsequent filial generations.

Mesophyll protoplasts from leaves of aseptically grown shoot tips of Diplotaxis muralis were isolated (6.2-7.1×10(5) protoplasts/g fresh weight of tissue) using one step enzyme digestion. The protoplasts (71% viability) underwent divisions (4.2+0.1%) on plating in M8PS2 medium and ultimately formed calli with 0.45+0.03% plating efficiency. Plant regeneration could be achieved both through embryogenesis and organogenesis. The efficiency of plant regeneration through organogenesis was 9 times higher than embryogenesis. Forty eight out of 52 plants regenerated so far from 3 independent experiments were normal with respect to fertility and meiotic chromosomal behavior.

Two trace elements, copper (Cu) and zinc (Zn) in serum are elevated in cancer patients since both areconstituents of super oxide dismutase (SOD) as metalloenzyme, the enzyme that scavenge free radicals andactivated oxygen species in the body. The study of 52 cancer patients comprising of 31 carcinoma stomachand 21 breast cancer showed the elevation of both of these trace elements in serum when compared to 32healthy controls and effected the kidney functions as a consequences. Serum Cu and Zn were estimated byAtomic Absorption Spectrometer (AAS), analyzed statistically by student "t" test and marked elevationwas observed in cancer patient compared to healthy controls. Serum Cu and Zn values were 98.13 ± 17.49μg/dl 99..57 ± 13.91 μg /dl respectively in 38 healthy subjects and these trace metals were 156.23 ± 31.02 μg/dl and 171.86 ± 35.15 μg/dl in 52 cancer patients showing significant elevation (P

A soil isolate of Bacillus stearothermophilus was found to synthesize thermostable alpha-amylase. The enzyme was purified to homogeneity by ammonium sulfate fractionation and IECC on DEAE-cellulose column. The purified enzyme was considered to be a monomeric protein with a molar mass of 64 kDa, as determined by SDS-PAGE. The enzyme showed a wide range of pH tolerance and maximum activity at pH 7.0. The temperature tolerance was up to 100 degrees C with more than 90% catalytic activity; the maximum activity was observed at 50 degrees C. Divalent metal ions exhibited inhibitory effect on the enzyme activity. However, proteinase inhibitor did not react positively.

Degraded gum, obtained from the waste liquor after degumming of decorticated ramie with hot dilute alkali, can replace one-third of the urea-formaldehyde resin required for making jute-stick particle board.

To improve the yield of lysine by the isolate, auxotrophic mutants were isolated. Among the mutants, only one auxotrophic mutant required vitamin B12. This mutant produced alpha-alanine. About 200 mutants resistant to the lysine analog S-(2-aminoethyl)-L-cysteine were isolated and some of them produced well above the wild type.

DNAs have been isolated from various Oryza species and studied using physical techniques. The percent of guanine plus cytosine has been determined by thermal denaturation. While the base composition varied between the species, no heterogeneity in the base pair distribution was observed. Renaturation kinetics data of DNAs from different species show that the proportion of repeated DNA sequences vary considerably depending on the DNA content per cell, whereas the nonrepetitive DNA component remains relatively constant. These results suggest that in addition to a small range of DNA variation between the species, changes in the base composition and proportion of repeated sequences have accompanied divergence of the species within the genus.

The need to transfer genetic traits from Diplotaxis muralis (2n=42) to Brassica juncea (2n=36), a major oil seed crop of the tropical world, was realised. Since the two plant types are sexually incompatible, attempts were made to evolve parasexual hybrids as the result of protoplast fusion. Protoplasts of hypocotyl-derived calli of two cultivars of B. juncea were fused with normal and γ-irradiated mesophyll protoplasts of Diplotaxis muralis. Regeneration of 110 plants from the fused products was successfully achieved. Upon analysis of some of them, we realised that true somatic hybrids and partial somatic hybrids had been generated. Thus the primary goal of evolving intergeneric hybridisation products between these two plant types was fulfilled.

In vitro culture ofBrassica alba anthers on a growth medium containing inorganics of KB5 and organics, iron, sucrose and hormones of B5 resulted in a very high response of anthers (93.75%) towards callus induction. All the calli transferred to regeneration media responded favourably even after six months of callus induction. Numerous torpedo-shaped embryoids developed in clusters at many sites from each callus mass. Secondary embryogenesis and multiple shoot formation was also observed in many cases. The number of embryoids and plantlets produced by one embryogenic anther were as high as 169.8 and 17 respectively. 87% of the regenerated plants were haploids.

A glucomannan, isolated by fractionation of the alkali-soluble hemicelluloses of sunn-hemp fibre (crotalaria juncea linn), had [α] -45° and, on hydrolysis, yielded glucose, mannose, and xylose in the molar ratios 1.2:1:0.07. The methylated polysaccharide contained an average of ≈45 hexose residues, whereas the corresponding value for the nitrate derivative was 49. Structural studies showed that the glucomannan has a main chain of (1→4)-linked β-D-glucopyranosyl and -mannopyranosyl residues. The molecule appears to have an average of one branch point, through position 6 of both glucose and mannose residues of the main chain. Both D-glucopyranosyl (87%) and d-mannopyranosyl (13%) residues were present as non-reducing end groups. D-glucose and d-mannose occur in the chain both as alternate and contiguous units.

SUMMARYNuclear DNA syntheses have been measured microspectrophotometrically in course of meiotic nuclear development inNeurospora crassa. The purpose of the study has been to establish the timing of these DNA syntheses in relation to meiosis and in the formation of its final products in an ideal genetic material, where the products of the meiotic division can be recovered and identified. Spectrophotometric analysis has indicated that the last premeiotic DNA replication is completed before caryogamy; a postmeiotic DNA replication takes place at the tetrad of the nuclei level; and finally a second postmeiotic DNA replication occurs in the ascospores to result in eight binucleated ascospores. The timing of postmeiotic replication is compatible with the models explaining gene conversion through the postulated mechanisms involving heteroduplex formation.

Regeneration of rice plantlets (Oryza sativa L.) from calli originated from leaf sheath cells was made possible. This was possible in tissues initially grown in media containing 2.4-D (2.4-dichlorophenoxyacetic acid) at low temperature and illumination. The slow growing tissues were subsequently subjected to growth conditions at an elevated temperature and higher illumination with addition of kinetin and IAA and without 2.4-D. The suitability of leaf sheath cells for protoplast technology is indicated by this success.

Pineapple-fibre holocellulose was extracted with alkaline solutions of increasing concentration to give hemicellulose fractions I–III. Purified fraction I (major component) contained d -xylose, l -arabinose, and 4-O-methyl- d -glucuronic acid in the molar proportions 10:0.6:1, and an average of ∼116 sugar residues, whereas its methylated product contained ∼94 sugar residues. Structural studies of the hemicellulose and its arabinose-free portion showed it to be a (1→4)-linked β- d -xylan with approximately every tenth residue carrying a 4-O-methyl-α- d -glucopyranosyluronic acid group at O-2 and every sixteenth residue carrying an l -arabinofuranosyl group at O-3.

Isolated mesophyll protoplasts of Brassica juncea (L.) Czern., cv. RLM 514 upon culture in suitable growth medium, regenerated cell wall, underwent cell division and formed cellular colonies. Subsequent induction of embryoid (embryogenesis) and shoot bud (organogenesis) formations in such cell masses resulted in regeneration of 186 and 42 plantlets respectively.

In females homozygous for the meiotic mutant c(3)G, a reasonable amount of intergenic recombination was found to occur, while no intragenic recombination could be detected at the white locus. On the other hand, a significant increase in both inter-and intragenic recombination was observed in females heterozygous for the same mutation. These results are discussed in the context of the synaptonemal complex formation during chromosome pairing in the mutant.

Hypocotyl calli-derived protoplasts of two cultivars of Brassica juncea (2n=36), a major oil-seed crop, were fused with normal as well as γ-irradiated mesophyll protoplasts of Eruca sativa (2n=22). The irradiation of the Eruca fusion partner increased the plating efficiency as well as the morphogenic potentiality of the fusion products over the normal fusion. Fertile plants could be regenerated from such fusion products. Analysis of 63 out of 181 plants regenerated showed that, indeed, 11 somatic hybrids (2n=58) and 10 partial somatic hybrids (chromosome number ranged between 50 and 56) had been obtained. Pollen viability (0%–82.9%) and seed set (0%–50%) of the hybrids indicated them to be useful for future studies.

Protoplasts isolated from mesophyll cells of Eruca sativa Lam., cultured on suitable medium, underwent sustained cell divisions to form calli. The plating efficiency was found to be 0.4%. The protoplast-derived calli subsequently produced plantlets through organogenesis (15.71%) and somatic embryogenesis (11.25%). Regenerated plants exhibited normal appearance. These results indicate potential to introgress desirable traits from this wild crucifer into important oilseed and cole Brassicas by protoplast fusion and hybrid recovery.