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1.
2种新型基因工程长效人胰岛素类似物   总被引:8,自引:0,他引:8  
甘精胰岛素和地特胰岛素是2种新型的人胰岛素类似物。虽然他们都通过基因工程的方法生产,药效能持续24h,无明显的波峰和波谷,是真正意义上的基础胰岛素,但是这2种长效胰岛素的分子结构、长效机制、生产工艺各不相同,在临床使用上也有各自的利弊。  相似文献   

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In recent years, the decreased efficacy of existing antibiotics toward management of emergent drug-resistant strains has necessitated the search for novel antibiotics from natural products. In this regard, Bacillus sp is well known for producing variety of secondary metabolites of potential use. Therefore, we performed an investigation to isolate and identify Bacillus sp from oral cavity for production of novel antimicrobial compounds. We extracted, purified, and identified a novel bioactive compound by B. megaterium (KC246043.1). The optimal production of compound was observed on de Man Rogosa and Sharpe broth by incubating at 37?°C, and pH 7.0 for 4?days. The bioactive compound was extracted by using n-butanol (2:1 v/v), purified on TLC plates with detection at Rf 7.8?cm; further characterized and identified as a cyclic ploypeptide sharing structural similarity with bacitracin. Minimum inhibitory concentration of bioactive compound was found to be 0.25, 0.5, 1.0, 3.125 and 6.25?μg/ml against Micrococcus luteus ATCC10240, Salmonella typhi ATCC19430, Escherichia coli ATCC35218. Pseudomonas aeruginosa ATCC27853 and Staphylococcus aureus ATCC25923 respectively, with no activity against Candida albicans ATCC10231. Our findings have revealed a novel cyclic peptide compound from B. megaterium with broad spectrum antimicrobial activity against both Gram positive and Gram negative bacteria.  相似文献   

4.
A new semaphorin inhibitor xanthofulvin was isolated from the cultured broth of a fungus Penicillium sp. SPF-3059 along with a known compound vinaxanthone by solvent extraction and bioassay-guided fractionation. The tautomeric structure of xanthofulvin was determined by spectroscopic analyses. The two compounds exhibited significant semaphorin inhibitory activity with IC50 values of 0.09 and 0.1 microg/ml, respectively, in semaphorin3A-induced growth cone collapse assay using cultured chick dorsal root ganglia neurons.  相似文献   

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Tyrosinase is a key enzyme in the synthesis of melanin and is widely distributed in animals, plants, and microorganisms. As excessive melanin production causes not only hyperpigmenting effects on human skin but also melanosis in various foods, an inhibitor of tyrosinase has become of interest lately from a practical point of view. In the present study, we purified the tyrosinase inhibitor produced by Trichoderma viride strain H1-7 from a marine environment. The purified inhibitor showed a single peak on HPLC. The chemical structure of this compound was determined by NMR and mass spectrometry analyses. The structure was the same as homothallin II that has been isolated as an antibiotic from T. koningii and T. harzianum. The inhibitor showed competitive inhibition against mushroom tyrosinase.  相似文献   

7.
Three new members of the fluostatin family, fluostatins C-E, were discovered in a culture filtrate extract of strain Acta 1383 during an HPLC screening program. The producing strain belongs to the genus Streptomyces and is closely related to type strains classified in the Streptomyces lavendulae 16S rRNA subclade. Fluostatins are named by their characteristic fluorenone chromophore. Fluostatin C shows moderate activity against selected human tumor cell lines.  相似文献   

8.
New antibiotics, OS-4742 A1, A2, B1 and B2, were isolated from the culture broth of the strain OS-4742, which was designated as Streptomyces matensis subsp. vineus. These compounds have anthracycline chromophores and sugar moieties, but do not contain nitrogen. They possess antimicrobial activities against Gram-positive bacteria and antitumor activities against S-180 solid tumor on mice.  相似文献   

9.
A novel vancomycin analog, N-demethylvancomycin, is produced by a soil isolate collected in Yucatan, Mexico. Taxonomic studies indicated this microorganism, designated NRRL 15232, is a strain of Nocardia orientalis. Unlike some glycopeptide antibiotics, virtually none of the N-demethylvancomycin synthesized remained bound to the cells of the producing culture. Antibiotic production was markedly depressed by the addition of orthophosphate to the fermentation medium. Enrichment of the medium with tyrosine, p-hydroxyphenylglycine, p-hydroxyphenylglyoxylic acid, or leucine, all putative precursors of the aglycone, stimulated the biosynthesis of N-demethylvancomycin.  相似文献   

10.
Radioligand binding studies were performed in membranes of human cerebral cortex using [125I]Tyr3-octreotide in the presence of 5 mM MgCl2, [125I]SRIF-14 ([125I]Tyr11-SRIF-14) and [125I]CGP 23996 ([125I]c[Asu-Lys-Asn-Phe-Phe-Trp-Lys-Thr-Tyr-Thr-Ser]) both in the presence of 120 mM NaCl, to characterise the nature of the somatostatin (SRIF) receptors. The pharmacological profile of human brain SRIF recognition sites was compared with that of recombinant human SRIF1 (sst2-sst3-sst5) or SRIF2 receptors (sst1-sst4) and with that of native rat sst1, sst2 and sst4 receptors. [125I]Tyr3-octreotide labelled binding sites in human cerebral cortex: B max = 238 ± 36 fmol/mg protein and pKd = 9.73 ± 0.08. The pharmacological profile of [125I]Tyr3-octreotide labelled sites correlated very significantly with that of recombinant human sst2 receptors (r = 0.98) and much less with those of recombinant human sst3 (r = 0.65) or sst5 receptors (r = 0.72). The correlation between [125I]Tyr3-octreotide binding to native sst2 receptors in human and rat cerebral cortex was also highly significant (r = 0.97). [125I]SRIF-14 and [125I]CGP 23996 binding (performed in the presence of 120 mM NaCl) in the human cerebral cortex identified very similar populations of sites B max = 44 ± 7 and 36 ± 5 fmol/mg protein and pKd = 9.44 ± 0.08 and 9.48 ± 0.10, respectively. The pharmacological profiles of the sites labelled with [125I]SRIF-14 and [125I]CGP 23996 correlated highly significantly with those of recombinant human sst1 (r = 0.97–0.99) or sst4 receptors (r = 0.91–0.94). Similarly, the correlations between [125I]SRIF-14 or [125I]CGP 23996 binding in human cortex and [125I]SRIF-14 binding to native sst1 sites in rat cerebral cortex were also highly significant (r = 0.97 and 0.94, respectively). Finally, the pharmacological profile of native rat lung sst4 sites determined with [125I]LTT-SRIF-28 ([Leu8,D-Trp22,125I-Tyr25]SRIF-28) correlated with [125I]SRIF-14 and [125I]CGP 23996 binding in human cortex; r = 0.91 and 0.87, respectively. The present data show that in human cerebral cortex, [125I]Tyr3-octreotide labels SRIF1 receptor sites which are best characterised as of the sst2 type, whereas [125I]SRIF-14 and [125I]CGP 23996 (both in the presence of 120 mM NaCl), label sites which fit almost equally well with sst1 or sst4 receptors and therefore are best described as of the SRIF2 type. Under the conditions used, there was no evidence that either of these ligands would label sst3 or sst5 receptors in human cerebral cortex. Received: 8 August 1996 / Accepted: 8 November 1996  相似文献   

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A strong antistaphylococcal peptide (ASP-1) from Bacillus subtilis URID 12.1 strain that is active against cefoxitin- and methicillin-resistant Staphylococcus aureus clinical isolates was purified to homogeneity by solvent extraction, silica gel-based adsorption chromatography and reversed-phase high-performance liquid chromatography. The peptide sequence of ASP-1 as determined by MALDI-TOF/MS and ESI-FTICR-MS was acetylated Phe-Thr-Ala-Val-Dhb-Phe-Ile/Leu. The peptide was further analysed by alkaline hydrolysis, ESI-Q-TOF-MS and an ion mobility assay, which detected the presence of a lactone ring in the intact peptide and a cyclic nature, subsequently revealing the linearised peptide sequence as acPhe-Leu-Phe-Thr-Val-Ala-Dhb. Based on the molecular mass (804.5 Da), peptide sequence and amino acid composition, ASP-1 was identified as a lactone ring-containing peptide similar to TL-119, a poorly studied cyclic depsipeptide. Circular dichroism spectroscopy revealed its predominantly random structure in aqueous solution and its β-sheet conformation in methanol. Minimum inhibitory concentrations (MICs) of the purified peptide against S. aureus and methicillin-resistant S. aureus (MRSA) ranged from 2?µg/mL to 64?µg/mL. At sub-MICs and 1× MIC, ASP-1 showed a strong antibiofilm characteristic. ASP-1 at a concentration of 128?µg/mL did not show haemolytic activity, and no cytotoxicity was observed against hepatic carcinoma and breast carcinoma cell lines at the same concentration. Peptide ASP-1 with anti-MRSA and antibiofilm abilities and non-haemolytic and non-cytotoxic properties has not been reported previously. These findings suggest that it may serve as a lead molecule for developing alternative topical antibacterial agents.  相似文献   

13.
A new secondary metabolite was detected in the culture extract of Streptomyces sp. AK 409 by HPLC-diode-array screening. The metabolite was identified as pyrocoll, which is known to be a constituent of cigarette smoke. Pyrocoll is known as a synthetic compound, but until now had not been isolated as a natural product from a microorganism. The compound showed biological activity against various Arthrobacter strains, filamentous fungi, several pathogenic protozoa, and some human tumor cell lines.  相似文献   

14.
Homogeneous dispersions of insulin and recombinant human growth hormone (rh-GH) in tristearin/phosphatidylcholine/PEG mixtures (1.3:1.3:0.25:0.15 w/w ratio) were processed by supercritical carbon dioxide gas micro-atomisation to produce protein-loaded lipid particles. The process yielded spherical particles, with a 197 ± 94 nm mean diameter, and the insulin and rh-GH recovery in the final product was 57 ± 8% and 48 ± 5%, respectively. In vitro, the proteins were slowly released for about 70–80 h according to a diffusive mechanism. In vivo, the insulin and glucose profiles in plasma obtained by subcutaneous administration of a dose of particles containing 2 μg insulin to diabetic mice overlapped that obtained with 2 μg of insulin in solution. Administration of a dose of particles containing 5 μg insulin resulted in faster and longer glycaemia reduction. Oral administration of 20 and 50 μg insulin equivalent particles produced a significant hypoglycaemic effect. The glucose levels decreased since 2 h after administration, reaching about 50% and 70% glucose reduction in 1–2 h with the lower and higher dose, respectively. As compared to subcutaneous administration, the relative pharmacological bioavailability obtained with 20 and 50 μg equivalent insulin particles was 7.7% and 6.7%, respectively. Daily subcutaneous administration of 40 μg of rh-GH-loaded particles to hypophysectomised rats induced similar body weight increase as 40 μg rh-GH in solution. The daily oral administration of 400 μg rh-GH equivalent particles elicited a slight body weight increase, which corresponded to a relative pharmacological bioavailability of 3.4% compared to subcutaneous administration.  相似文献   

15.
AB3217-A, a novel anti-mite substance, was isolated from the fermentation broth of a streptomycete strain. The strain was isolated from a soil collected at Kita-azumi, Nagano Prefecture, Japan, and identified as Streptomyces platensis AB3217. AB3217-A was purified by Amberlite IR120B, Diaion HP-20 and CM-Sephadex C-25 column chromatographies. The molecular formula was determined as C17H23NO7 by elemental analysis, MS and 13C NMR spectroscopy. The structure of AB3217-A was determined to be (1R,3S,4S,7R,8R,11R,12S,13R)-4,12,13-trihydroxy-8-(4-methoxy phenyl)-6-aza-2,9,14-trioxatricyclo-[9.2.1.0(3,7)]tetradecane by spectroscopic analysis and X-ray crystallographic analysis. The molecule of AB3217-A has unique structure that deacetylanisomycin and beta-D-xylofuranose linked through glycosidic bond and ether bond resulting in the formation of nine-membered ring. AB3217-A showed marked activity against the two spotted spider mite, Tetranychus urticae.  相似文献   

16.
A47934, a novel glycopeptide-aglycone antibiotic, is produced by a strain of Streptomyces toyocaensis, NRRL 15009. A47934 is unique among reported glycopeptides in that it contains a sulfate ester. Like several other glycopeptides, the majority of the A47934 produced remained associated with the producing biomass, from which it could be released into aqueous media by alkalization. Antibiotic biosynthesis was depressed when initial levels of phosphate phosphorus in the medium exceeded the normal level of 35 micrograms/ml. Enrichment of the fermentation medium with tyrosine depressed A47934 yields while enrichment with p-hydroxyphenylglycine or p-hydroxyphenylglyoxylic acid stimulated antibiotic biosynthesis.  相似文献   

17.
The actinobacterium strain ABH26 closely related to Saccharothrix xinjiangensis, isolated from an Algerian Saharan soil sample, exhibited highly antagonist activity against Gram-positive bacteria, yeasts and filamentous fungi. Its ability to produce antimicrobial compounds was investigated using several solid culture media. The highest antimicrobial activity was obtained on Bennett medium. The antibiotics secreted by strain ABH26 on Bennett medium were extracted by methanol and purified by reverse-phase HPLC using a C18 column. The chemical structures of the compounds were determined after spectroscopic (1H NMR, 13C NMR, 1H-1H COSY and 1H-13C HMBC spectra), and spectrometric (mass spectrum) analyses. Two new cyanogriside antibiotics named cyanogriside I (1) and cyanogriside J (2), were characterized along with three known caerulomycins, caerulomycin A (3), caerulomycin F (4) and caerulomycinonitrile (5). This is the first report of cyanogrisides and caerulomycins production by a member of the Saccharothrix genus. The minimum inhibitory concentrations (MIC) of these antibiotics were determined against pathogenic microorganisms.  相似文献   

18.
Two new human chymase inhibitors, SPF-32629A and B, were isolated from the cultured broth of Penicillium sp. SPF-32629. These structures were determined by spectroscopic methods and identified as new pyridone compounds. SPF-32629B was the carboxylated derivative of SPF-32629A. SPF-32629A and B specifically inhibited human chymase among four serine proteases tested with the IC50 of 0.25 and 0.42 microg/ml, respectively.  相似文献   

19.
Three human phenol sulfotransferases, provisionally named SULT1A1, 1A2 and 1A3, show 91-96% homology of their amino acid sequences and are encoded by neighbouring gene loci. Functional genetic polymorphisms are known for two of these sulfotransferases. In SULT1A1, a G to A transition leads to an Arg213 to His exchange and eliminates a Bsp143II restriction site. SULT1A1*His shows lower enzyme activity and thermostability than SULT1A1*Arg. In SULT1A2, an A to C transversion causes an Asn235 to Thr exchange and introduces a BpiI restriction site. Enzyme SULT1A2*Thr is less active than SULT1A2*Asn. These substitutions were detected by restriction fragment length polymorphism analyses of genomic sequences amplified by polymerase chain reaction. Despite the high similarity between the different human SULT1A genes, it was possible to amplify specifically the polymorphic parts of either SULT1A1 or 1A2, but not the homologous sequences of the other SULT, by setting the forward primer into intron 6. DNA from 300 adult male Caucasian subjects was analysed. Allele frequencies were 0.63 and 0.37 for SULT1A1*Arg and *His, and 0.62 and 0.38 for SULT1A2*Asn and *Thr, respectively. The frequency of the haplotype SULT1A1*Arg/SULT1A2*Asn (0.61) was nearly as high as the allele frequencies of its components. The same was observed for the haplotype SULT1A1*His/SULT1A2*Thr, whose frequency was 0.35. In contrast, haplotypes 1A1*Arg/1A2*Thr and 1A1*His/1A2*Asn were very rare. Their frequencies (0.02 each) were less than 10% of the figures expected in an independent distribution. The results demonstrate a strong association of the alleles producing the more active enzyme variants (SULT1A1*Arg and SULT1A2*Asn) and of those encoding the less active variants (SULT1A1*His and SULT1A2*Thr).  相似文献   

20.
Endusamycin formerly called CP-63,517 (C47H77O14Na), is a novel polycyclic ether antibiotic produced by a new strain of Streptomyces endus subsp. aureus (ATCC 39574). Recovery, fractionation and purification were achieved using standard procedures. Forms include the endusamycin free acid, mp 95 approximately 105 degrees C, lambda max 232 nm (log E 4.16), [alpha]25D +47.4 degrees (c 0.5, methanol) and a crystalline sodium salt, mp 215 approximately 220 degrees C, lambda max 232 nm, (log E 4.15), [alpha]25D +25 degrees (c 0.5, methanol). The structure is shown below, Fig. 1. Endusamycin exhibited; antibacterial activity, in vitro against Gram-positive and anaerobic bacteria, effectiveness against coccidia in poultry, and stimulation of propionic acid production in an in vitro system.  相似文献   

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