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1.
In attempt to obtain an efficient mutant for the production of flavin-adenine dinucleotide (FAD) from flavin mononucleotide (FMN) and adenine, Sarcina lutea. IAM 1099 was treated with N-methyl-N′-nitro-N-nitrosoguanidine, and a purine base-requiring and adenosine deaminaseless mutant was obtained as the favorable one. The mutant accumulated more than three fold as much as that by the parent strain.  相似文献   

2.
A study was made to develop a new method for the production of flavine-adenine dinucleotide (FAD) from riboflavine and adenine by a mutant of Sarcina lutea deficient in the enzyme adenosine deaminase. It was found that this strain could convert exogenously supplemented riboflavine to extracellular FAD. The yields of FAD were increased by addition of D-cycloserine in the culture medium. The culture conditions for FAD production were investigated under the addition of D-cycloserine, and increased production of FAD was observed with the addition of an appropriate amount of thiamine, acetate, and sodium ion. The yield of 0.7 g/liter was obtained in the optimal culture in 5 days. Accumulated FAD was readily isolated by adsorption chromatography and ion-exchange chromatography in a 70% yield.  相似文献   

3.
Summary Microbial esterification of primary and secondary short chain alcohols with butyric acid in organic solvent has been studied. A screening for 2-octylbutyrate hydrolysis between microorganisms belonging to different genera allowed the selection of 12 microbial strains able to hydrolyze this substrate. The potential of these microorganisms in catalyzing ester formation was checked for various 1- and 2-alkylbutyrate derivatives:Rhizopus delemar,Rhizopus oryzae andSarcina lutea promoted both 1- and 2-alkylbutyrate synthesis with almost complete molar conversion of the primary alcohols, whileAspergillus niger andYarrowia lipolytica only catalyzed 1-alkanol esterification.  相似文献   

4.
The review of works on amine oxidases of microorganisms is presented. Preparation, physical-chemical and kinetic properties of amine oxidases from archaebacteria Methanosarcina barkery, group of methane-producing archaebacteria, eubacteria, Sarcina lutea, Micrococcus rubens, M. lutea, representatives of Enterobacteriaceae family, such as Klebsiella and Escherichia, are considered. Besides, the amine oxidases obtained from mycelium of fungus Aspergillus niger are described. The works are considered, are performed both using classical biochemistry methods based on studying of substrate–inhibitor enzyme specificity and using gene engineering.  相似文献   

5.
Bacterial production of 4-hydroxy(3,4-d)pyrazolopyrirnidine riboside (AP–R) was studied. Seven among 73 tested strains were found to produce AP–R through N-ribosyl transfer reaction between uridine and 4-hydroxy(3,4-d)pyrazolopyrimidine (allopurinol). AP–R was produced by the cell-free extract of Erwinia carotovora and was isolated in crystals from the reaction mixture. The crystalline AP–R was characterized by spectroscopic data and was confirmed to be β-1-ribosyl allopurinol. AP–R could not substitute for inosine to support the growth of a nonexacting purine base-requiring mutant of Sarcina lutea.  相似文献   

6.
Penicillin amidohydrolase productivity of four locally isolated bacterial species is described. Organisms were identified asEscherichia coli, Pseudomonas aeruginosa, Sarcina lutea andBacillus megaterium. Highest enzyme productivity of 3.2 U/mL with a corresponding dry cell mass of 4.5 g/L was recorded fromS. lutea.  相似文献   

7.
Summary It has been demonstrated that the carotenoid pigments of Sarcina lutea prevent photodynamic killing by either exogenous or endogenous photosensitizers.Evidence has been presented which suggests that the locus of the lethal photooxidation is in or on the cell membrane.  相似文献   

8.
Assay organisms Saccharomyces cerevisiae and Sarcina lutea, when suspended in a weak buffer and stored at refrigerator temperatures, are stable for 1 year or more.  相似文献   

9.

Background  

Engineering microorganisms to improve metabolite flux requires detailed knowledge of the concentrations and flux rates of metabolites and metabolic intermediates in vivo. Fluorescence resonance energy transfer sensors represent a promising technology for measuring metabolite levels and corresponding rate changes in live cells. These sensors have been applied successfully in mammalian and plant cells but potentially could also be used to monitor steady-state levels of metabolites in microorganisms using fluorimetric assays. Sensors for hexose and pentose carbohydrates could help in the development of fermentative microorganisms, for example, for biofuels applications. Arabinose is one of the carbohydrates to be monitored during biofuels production from lignocellulose, while maltose is an important degradation product of starch that is relevant for starch-derived biofuels production.  相似文献   

10.
Disruption of Bacterial Cells by a Synthetic Zeolite   总被引:1,自引:1,他引:0       下载免费PDF全文
The use of a synthetic zeolite (type 4A, Union Carbide Corp., Linde Div., New York, N.Y.) in a procedure for the preparation of pure cell wall fractions proved successful for many gram-positive, gram-negative, and acid-fast bacteria, as well as for some fungi. The technique, however, was found to be limited in effectiveness for Rhodospirillum rubrum, Gaffkya tetragena, and Sarcina lutea, and not applicable to preparations of heat killed microorganisms. The possible mechanisms of zeolite action, together with the effect of the disruptive procedure on the chemical composition of cell wall fragments, were investigated also.  相似文献   

11.

Background

Friedreich ataxia is a neurodegenerative disease caused by the lack of frataxin, a mitochondrial protein. We previously demonstrated that frataxin interacts with complex II subunits of the electronic transport chain (ETC) and putative electronic transfer flavoproteins, suggesting that frataxin could participate in the oxidative phosphorylation.

Methods and Findings

Here we have investigated the effect of riboflavin and its cofactors flavin adenine dinucleotide (FAD) and flavin mononucleotide (FMN) in Saccharomyces cerevisiae and Caenorhabditis elegans models of frataxin deficiency. We used a S. cerevisiae strain deleted for the yfh1 gene obtained by homologous recombination and we assessed growth in fermentable and non-fermentable cultures supplemented with either riboflavin or its derivates. Experiments with C. elegans were performed in transient knock-down worms (frh-1[RNAi]) generated by microinjection of dsRNA frh-1 into the gonads of young worms. We observed that FAD rescues the phenotype of both defective organisms. We show that cell growth and enzymatic activities of the ETC complexes and ATP production of yfh1Δ cells were improved by FAD supplementation. Moreover, FAD also improved lifespan and other physiological parameters in the C. elegans knock-down model for frataxin.

Conclusions/Significance

We propose that rescue of frataxin deficiency by FAD supplementation could be explained by an improvement in mitochondrial respiration. We suggest that riboflavin may be useful in the treatment of Friedreich ataxia.  相似文献   

12.
Microorganisms that produce ribavirin(1-β-d-ribofuranosyl-1,2,4-triazole-3-carboxamide; virazole®) directly from pyrimidine nucleosides and TCA (1,2,4-triazole-3-carboxamide) were screened from our stock cultures. Of the 400 strains tested, 16 were isolated as ribavirin-producers from uridine or cytidine. In particular, Enterobacter aerogenes AJ 11125, Bacillus brevis AJ 1282 and Sarcina lutea AJ 1212 were found to possess potent activities of ribavirin production from them. In the presence of intact cells of Enterobacter aerogenes AJ 11125, which was selected as the best strain, 110.2mm and 67.6 mm ribavirin were produced from uridine and cytidine, respectively, on 96 hr reaction at 60°C. In addition, this strain could also produce ribavirin from guanosine, but could not produce it from orotidine, which is also a pyrimidine nucleoside.  相似文献   

13.
通过DNS法测定羊瘤胃源功能性细菌产生的纤维素酶和淀粉酶的活力,福林酚法测定产生的蛋白酶的活力,检测细菌产生酶的特性。同时检测菌株的发酵液对大肠埃希菌(ATCC25922)、副溶血弧菌(ATCC17802)、藤黄八叠球菌(HY78)和产气杆菌(AS1489)等指示菌的抑制能力,分析它们的抑菌活性。结果表明,羊瘤胃源细菌C13产生的纤维素酶活力最高,产酶量也最高;而细菌C5产淀粉酶活力和蛋白酶活力最高,产生淀粉酶和蛋白酶的能力也最高。抑菌活性检测发现,细菌C9对副溶血弧菌(ATCC17802)有很高的抑制作用,而细菌C12对大肠埃希菌(ATCC25922)的抑制能力最明显。  相似文献   

14.
Summary It is demonstrated for the first time that a species from the genusHumicola is a potential source of acid protease. A strain was classified by morphological investigations asHumicola lutea. The influence of constituents of the culture medium on the growth and acid protease production ofH. lutea 72 in submerged cultivation in flasks was investigated. An improved medium was devised for future studies. The optimal aeration rate, inoculum level and cultivation time were determined. A maximal proteolytic activity of 670 g tyrosine liberated from casein ml–1 culture filtrate min–1 at pH 3.0 was obtained.  相似文献   

15.
The course of the reaction produced by intracutaneous injection of the toxin of Lyngbya majuscula Gomont is that of a severe acute inflammatory reaction. No protective or sensitizing effect is induced by a previous exposure. The response from intravenous injection into a rat indicates that the toxin acts as a general cell toxin. The protozoan Tetrahymena pyriformis and rabbit erythrocytes are lysed by the toxic principle, which also possesses antibacterial activity. Of the organisms tested, Mycobacterium species are markedly inhibited, while Bacillus cereus, Gaffkya tetragena, and Sarcina lutea are slightly to moderately inhibited. Other components of the alga, which are steam distillable, have been found to have antibacterial activity but are not involved in the skin reaction.  相似文献   

16.
The cloning of a bifunctional FAD synthetase gene, which shows flavokinase and FMN adenylyltransferase activities, from Corynebacterium ammoniagenes was tried by hybridization with synthetic DNAs corresponding to the N-terminal amino acid sequence. The cloned PstI-digested 4.4 × 103-base (4.4-kb) fragment could not express the FAD synthetase activity in E. coli, but could increase the two activities by the same factor of about 20 in C. amminoagenes. The FAD-synthetase-gene-amplified C. amminoagenes cells were applied to the production of FAD from FMN or riboflavin. The productivity of FAD from FMN was increased four to five times compared with the parent strain, and reached a 90% molar yield. The productivity of FAD from riboflavin was increased about eight times, with a 50% molar yield. The addition of Zn2+ to the reaction mixtures for the conversion from riboflavin to FAD brought about the specific inhibition of adenylyltransferase activity and resulted in the accumulation of FMN.  相似文献   

17.
Fermentation of xylose from hydrolysate of acid-treated corn cob by Pichia stipitis is inhibited by acetic acid and lignin derivatives. In the present study, we have designed and implemented an immobilized cell culture for xylose to ethanol conversion from acid-treated corn cob hydrolysate without the removal of fermentation inhibitors. In this study, cultivations of suspended and immobilized Pichia were compared in terms of ethanol yield and productivity to investigate whether the cell immobilization could improve resistance to inhibitors. Cell immobilization clearly favored the fermentative metabolism in nondetoxified corn cob hydrolysate leading to an improvement of twofold ethanol productivity as compared to that achieved with suspension culture. Calcium alginate as an immobilization matrix was selected to immobilize Pichia cells. Concentrations of sodium alginate, calcium chloride, and fermentor agitation speed were optimized for ethanol production using statistical method. Statistical analysis showed that agitation speed had maximum influence on ethanol production by immobilized Pichia cells. In comparison to suspension culture, immobilization had a positive impact on the fermentative metabolism of Pichia, improving the ethanol yield from 0.40 to 0.43?g/g and productivity from 0.31 to 0.51?g/L/h for acid-treated corn cob hydrolysate.  相似文献   

18.
To develop an efficient method for the production of coenzyme A (CoA), optimal conditions for its formation from pantothenic acid, cysteine, and adenine were studied. A number of microorganisms were screened for production of CoA. Strains belonging to the genera Sarcina, Bacillus, Microbacterium, Micrococcus, and Serratia accumulated CoA. Among these, Sarcina lutea was selected as the best organism, and the culture conditions for the production of CoA were investigated with this organism. Under optimal conditions, 600 mug of CoA per ml was accumulated in the culture broth. CoA was readily isolated in high purity by the use of charcoal, diethylaminoethyl-cellulose, Sephadex G-25, and Dowex-50. Yields of isolated CoA were over 33% from culture broth.  相似文献   

19.
New N‐substituted‐2‐amino‐4,5,6,7‐tetrahydrothieno[2,3‐c]pyridine derivatives were synthesized employing a convenient one‐pot three‐component method and their structures were characterized by 1H‐NMR and single crystal X‐ray diffraction analysis. All the synthesized compounds were in vitro screened for antimicrobial activity against Gram‐positive (Sarcina lutea) and Gram‐negative bacteria (Escherichia coli). In this work, we introduced a chiral residue on the tetrahydropyridine nitrogen, the hitherto the less investigated position on this pharmacophore in order to explore the effect. The antibacterial results showed that the synthesized compounds were active only against Gram‐positive bacteria and the (R)‐enantiomers displayed a greater antimicrobial potency than their (S)‐counterparts. The structure–activity relationship here investigated may provide some interesting clues for future development of tetrahydrothienopyridine derivatives with higher antimicrobial activity.  相似文献   

20.
A procedure for obtaining crystalline preparations of tyramine oxidase of Sarcina lutea has been developed. The procedure included fractionation with ammonium sulfate, treatment with protamine sulfate and separation by column chromatographies on DEAE-cellulose, hydroxylapatite and sephadex G-150. The specific activity of enzyme was increased 5,700~ 6,000-fold through the procedure, over the crude cell extract. Crystals were prepared from solutions of the purified enzyme by adding solid ammonium sulfate. The crystals appeared as minute, highly refractive needles, with a bright yellow color.

With the use of crystalline preparations of tyramine oxidase of Sarcina lutea, substrate and inhibitor specificities of the enzyme were investigated. The enzyme oxidized tyramine and dopamine at almost the same rates. Other monoamines, diamines, polyamines and amino acids were not oxidized at all. The oxidation of tyramine proceeded as follows: Tyramine+O2+H2O→p-Hydroxyphenylacetaldehyde +NH3+H2O2. Ammonia and hydrogen peroxide were formed in stoichiometric amounts.

The enzyme was not inhibited by carbonyl reagents, such as hydroxylamine, hydrazine, semicarbazide and isoniazid, but was inhibited by p-CMB and iproniazid.  相似文献   

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