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51.
Effect of oilseed cakes on alpha-amylase production by Bacillus licheniformis CUMC305. 总被引:1,自引:1,他引:0 下载免费PDF全文
The effects of oilseed cakes on extracellular thermostable alpha-amylase production by Bacillus licheniformis CUMC305 was investigated. Each oilseed cake was made of groundnut, mustard, sesame, linseed, coconut copra, madhuca, or cotton. alpha-Amylase production was considerably improved in all instances and varied with the oilseed cake concentration in basal medium containing peptone and beef extract. Maximum increases were effected by a low concentration (0.5 to 1.0%) of groundnut or coconut, a high concentration (3%) of linseed or mustard, and an Rintermediate concentration (2%) of cotton, madhuca, or sesame. The oilseed cakes made of groundnut or mustard could completely replace the conventional peptone-beef extract medium as the fermentation base for the production of alpha-amylase by B. licheniformis. The addition of corn steep liquor to cotton, linseed, sesame, or madhuca cake in the medium improved alpha-amylase production. 相似文献
52.
Chandra M. Dwivedi Laurence T. Plante Roy L. Kisliuk Edward J. Pastore Surendra P. Verma Donald F.H. Wallach 《Archives of biochemistry and biophysics》1982,213(1):338-340
Dihydrofolate reductase from Lactobacillus casei and its complexes with NADPH and methotrexate yield well-resolved Raman spectra. The 1685-cm?1 Raman band assigned to the carboxamide of NADPH persists in the NADPH-enzyme binary complex but is absent from the NADPH-methotrexate-enzyme ternary complex. This is ascribed to stabilization of the polarized form of the carboxamide by H bonding to the NH and CO groups of Ala 6 and Ile 13 of the peptide backbone. 相似文献
53.
54.
Summary A method is described for non-radioactive labeling of total mRNA [poly(A)+ RNA] in plastic-embedded plant tissue sections. Oligo-deoxythymidylic acid (oligo-dT) labeled with digoxigenin-conjugated dUTP was used for in situ hybridization to poly(A)+ RNA in sections of tobacco (Nicotiana tabacum) anthers. The digoxigenin was immuno-stained using antidigoxigenin IgG and gold-labeled protein-A, followed by silver enhancement of the gold label. Reproducibly similar positive staining patterns were obtained with digoxigenin-labeled oligo-dT and polyuridylic acid [poly(U)], but not with a similarly labeled sense probe, poly(A). In the developing anthers, from the onset of meiosis to the production of pollen grains, labeling patterns were compatible with a gradual depletion of nuclear and chromosome-associated sporophytic mRNA molecules during prophase of meiosis, followed by postmeiotic production of gametophytic mRNA in microspore nuclei and the vegetative nuclei of the pollen grains.Abbreviations BSA
bovine serum albumin
- DIG
digoxigenin
- IgG
immunoglobulin-G
- oligo-dT
oligo-deoxythymidylic acid
- PAS-ABB
periodic acid Schiff-aniline blue black
- PBS
phosphate buffered saline
- poly(A)
polyadenylic acid
- poly(U)
polyuridylic acid
- SSC
standard saline citrate 相似文献
55.
A new technique for studying the effect of insulin on protein degradation is reported. The method is based on measuring the parallel release of a reutilizable and a nonreutilizable amino acid from muscle protein. Animals are prelabeled in vivo with [Me-3H]methionine which labels both the nonreutilizable 3-methylhistidine and the reutilizable methionine of tissue protein. The data presented show that insulin has only a trivial effect on the loss of 3-methylhistidine from muscle protein, while it substantially diminishes the efflux of methionine. The analysis of muscle protein confirms the observation that insulin causes the reincorporation of methionine and has a minimum effect on the loss of 3-methylhistidine. This supports the view that the major inhibitory effect of insulin on gluconeogenesis is the diversion of the flow of amino acids away from the gluconeogenesis pathway back toward protein synthesis. 相似文献
56.
A new antifungal antibiotic named acmycin was isolated from a soil streptomycete. Detailed comparative taxonomic studies showed
that the organism differed from three related species of streptomycetes. The organism was referred to asStreptomyces sp. AC2. The isolated antibiotic appears to be of polyene nature. 相似文献
57.
A soil actinomycete hydrolyzed collagen extracted from bovine Achilles tendon, calf skin, carp swim-bladder and rat tail tendon.
Glucose, mannose, aspartic acid and asparagine increased its collagenolytic activity which was optimum at 28 °C and at pH
7.2 – 7.5. Metallic ions, NaEDTA, cysteine, 4-chloromercuribenzoate, glutathione and sodium azide were inhibitory. 相似文献
58.
The effect of neurotensin on submaximally-stimulated hepatobiliary and pancreatic secretion was studied in 6 healthy subjects. An intravenous infusion of neurotensin 1.4 ± 0.3 pmol/kg/min, designed to reproduce plasma neurotensin immunoreactivity levels within the physiological range, produced a significant increase in pancreatic bicarbonate output. Plasma concentrations of pancreatic polypeptide rose by 83 ± 16 pmol/l and were associated with a small reduction in trypsin, but no significant change in bilirubin outputs. 相似文献
59.
Girish Chandra 《BioControl》1980,25(2):187-192
Three new techniques of rearing dryinids parasitising rice hoppers were developed, namely, laboratory rearing technique for
detailed observations, device for transporting and rearing field-collected hoppers to estimate percentage parasitism and a
breeding technique.
Résumé Trois nouvelles techniques d’élevage de dryiinides parasites des cicadelles du riz ont été mises au point. L’une pour l’élevage en laboratoire en vue d’observations précises, un système pour le transport et l’élevage de cicadelles récoltées dans la nature afin d’évaluer le pourcentage de parasitisme et une technique d’élevage permanent.相似文献
60.