Physiochemical properties of LIA-0191 A and B antibiotics

An antifungal antibiotic LIA-0191 was isolated from the mycelium by methanol extraction. It was shown with thin-layer chromatography that it consisted of components A and B. Component A was isolated with collumn chromatography on silica gel, recrystalization from the solvent mixture as a monocomponent crystalline substance. On the basis of the physicochemical and biological properties it was identified with sentacidin. Component B was obtained from preparation LIA-0191 by the method of counter-current distribution and recrystalization from methanol. Comparison of its physico-chemical and biological properties with those of the known purines and pyrimidine pyrrol showed that antibiotic LIA-0191 B is new.     

云南红豆杉内生放线菌TAR11活性代谢产物的初步研究

目的：初步研究从云南红豆杉植株根部筛选到的一株抗植物病害的内生放线菌TAR11的活性代谢产物性质。方法：以枯草芽孢杆菌为指示菌、以抑菌活性为指标,测定TAR11发酵液的最小抑菌浓度;用不同温度、pH值处理,了解活性物质的稳定性;用有机溶剂对活性物质萃取和溶解,并用纸层析对活性物质进行初步分类。结果：TAR11发酵液抗菌物质的最小抑菌浓度为0．78％,对温度敏感,在酸性和中性条件下稳定,可被三氯甲烷萃取,能溶于水、甲醇、乙醇、丙酮、乙醚。结论：低浓度的放线菌TAR11代谢产物能强烈抑制枯草芽孢杆菌活性,经纸层析实验初步鉴定为一类碱性抗生素。放线菌TAR11有望开发成为新一代生物药物。     

HA-1-92, A new antifungal antibiotic produced by Streptomyces CDRIL-312: Fermentation,isolation, purification and biological activity

A new antifungal antibiotic, HA-1-92, was isolated from the biomass of Streptomyces CDRIL-312, by extracting in butanol and further purified by silica gel column chromatography followed by preparative TLC. The antibiotic is presumed to be an oxohexaene macrolide and showed promising antifungal activity against yeasts and filamentous fungi including human and plant pathogens. It was found to be less toxic in mice than known oxohexaenes.     

Bacereutin, an antifungal antibiotic isolated from metabolites of Bacillus cereus CHU 130

An antifungal metabolite, bacereutin, was isolated from culture filtrate of Bacillus cereus CHU 130. The bacterium was isolated from soils collected in Changhwa County, Taiwan, and was grown in soybean meal-mannitol broth for production of the antibiotic metabolite. The antibiotic metabolite was isolated by adsorption column chromatography of Amberite XAD-2 and was purified by passing through the chromatographic columns packed with Dowex 50W-X8, Sephadex LH 20 and Biogel P-2. The antibiotic metabolite was soluble in water and 87% acetone, and was slightly soluble in methanol, but was not dissolved in n-propanol, n-butanol, acetone, benzene and ethyl acetate. The antibiotic metabolite was a heat-stable and ninhydrin-positive substance. The antibiotic activities of bacereutin were tested by means of the agar-diffusion plate method. The antibiotic metabolite inhibited the growth of Saccharomyces cerevisiae CHU 1, Paecilomyces variotii CHU 6, Rhizomucor miehei CHU 40 and Fusarium oxysportum CHU 98. Bacereutin was a ninhydrin-positive antifungal antibiotic.     

The preparation of iodinated vancomycin and its distribution in bacteria treated with the antibiotic

Vancomycin was radioactively labelled by iodination with (125)I.Iodinated vancomycin was only a little less potent as an antibiotic than vancomycin itself. It was shown, both by chromatography and differential absorption measurements, to combine with acyl-d-alanyl-d-alanine residues. Radioactive vancomycin was used to follow the fate of the antibiotic in bacteria that had been subjected to the least concentration required to inhibit growth. Most of the radioactivity was in the cell walls, although some was found in the membrane fraction. The latter proportion increased during longer incubations with the antibiotic. Pre-formed protoplasts adsorbed very little vancomycin. Mg(2+) removed labelled vancomycin from the mucopeptide of Bacillus licheniformis, but had little effect on the antibiotic adsorbed on Micrococcus lysodeikticus, either in vivo or on previously isolated cell walls. Specific peptide was shown to compete with cell walls for vancomycin and it also extracted from cell-wall samples the labelled compound that had been adsorbed on M. lysodeikticus living cells.     

Antibiotics of an aromatic nature from Pseudomonas cepacia]

A raw antibiotic has been isolated from culture fluid of strain Pseudomonas cepacia 5798. It was methylated and separated into individual components using the column and thin-layer chromatography. The isolated substances possessed antimicrobial activity; two of them were studied more in detail by the UV-, IR- and PMR-spectroscopy methods. Results of the study of physicochemical properties of methyl derivatives of antibiotics from P. cepacia permit supposing that the latter are aromatic substances with nitrogen atoms in the side chain.     

蜡梅种子抑菌成分研究

在抑菌活性追踪指导下,采用硅胶柱层析的方法。从蜡梅种子中分离得到一活性化合物A,经质谱、核磁共振波谱等技术鉴定为d－洋蜡梅碱。经杀虫活性和抑菌活性测定,该化合物对粘虫的幼虫无毒杀活性;对西瓜枯萎病菌、玉米小斑病菌、玉米大斑病菌、番茄早疫病菌均有显著的抑菌活性。其抑制中浓（EC50）分别为：3878．8、29．3、103．1、328．3mg／L,但对油菜菌核病菌无抑制活性。     

Characterization of an endophytic whorl-forming Streptomyces from Catharanthus roseus stems producing polyene macrolide antibiotic

An endophytic whorl-forming Streptomyces sp. designated as TS3RO having antifungal activity against a large number of fungal pathogens, including Sclerotinia sclerotiorum, Rhizoctonia solani, Colletotrichum gloeosporioides, Cryphonectria parasitica, Fusarium oxysporum, Pyrenophora tritici-repentis, Epidermophyton floccosum, and Trichophyton rubrum, was isolated from surface-sterilized Catharanthus roseus stems. Preliminary identification showed that Streptomyces cinnamoneus subsp. sparsus was its closest related species. However, strain TS3RO could readily be distinguished from this species using a combination of phenotypic properties, 16S rDNA sequence similarity, and phylogenetic analyses. Thus, the whorl-forming Streptomyces sp. strain TS3RO is likely a new subspecies within the Streptomyces cinnamoneus group. Direct bioautography on a thin-layer chromatography plate with Cladosporium cucumerinum was conducted throughout the purification steps for bioassay-guided isolation of the active antifungal compounds from the crude extract. Structural elucidation of the isolated bioactive compound was obtained via LC-MS spectrometry, UV-visible spectra, and nuclear magnetic resonance data. It revealed that fungichromin, a known methylpentaene macrolide antibiotic, was the main antifungal component of TS3RO strain, as shown by thin-layer chromatography bioautography. This is the first report of an endophytic whorl-forming Streptomyces isolated from the medically important plant Catharanthus roseus.     

Condensed tannin,an antibiotic chemical from Gossypium hirsutum

Antibiotic activity against Heliothis virescens was found in flower buds of Gossypium hirsutum, experimental stock Texas 254. Relatively low antibiotic activity was found in hexane extract, high activity in methanolic extract and residue, and no activity in acetone and water extracts. A condensed tannin having a molecular weight of 4850 was isolated from methanolic extract by column chromatography on Sephadex G-25. It was the major antibiotic component, 3.4% of the dried flower bud. The condensed tannin at 0.2% in the diet retarded larval growth by 84%.     

Oxidation of Elemental Sulfur to Thiosulfate by Streptomyces

Streptomyces sioyaensis, which produces the antibiotic siomycin, oxidizes elemental sulfur when added to the culture medium and accumulates thiosulfate in the fermented broth. The accumulated thiosulfate was isolated as the ammonium salt and was identified by melting point, IR spectrum, and paper chromatography. A variety of other streptomycetes also oxidized elemental sulfur and accumulated thiosulfate.     

Heterologous expression of the kanamycin biosynthetic gene cluster (pSKC2) in <Emphasis Type="Italic">Streptomyces venezuelae</Emphasis> YJ003

The pSKC2 cosmid, which has 32 kb and 28 open-reading frames, was isolated from Streptomyces kanamyceticus ATCC12853 as the gene cluster of kanamycin. This gene cluster includes the minimal biosynthetic genes of kanamycin with the resistance and regulatory genes. It was heterologously expressed in Streptomyces venezuelae YJ003, which has the advantage of fast growth, good efficiency of the transformation host, and rapid production of the aminoglycosides antibiotic. The isolated compound was analyzed by electrospray ionization–mass spectrometry, liquid chromatography–mass spectrometry, high-performance liquid chromatography, and tandem mass spectrometry and shows a molecular weight of 485 as kanamycin A.     

链霉菌FIM 95-F1产生的抗真菌抗生素S1

放线菌FIM 95-F1的形态特征、培养特性及生理生化特征和16S rDNA序列分析表明该菌属于Strepto-myces castelarensis的一个变种,暂定名为S.castelarensis FIM 95-F1。本研究利用高速逆流色谱分离和结晶法相结合的方法从放线菌FIM 95-F1胞内分离纯化抗真菌抗生素S1。化合物理化性质和UV、IR、MS以及NMR等波谱分析结果表明化合物S1与抗真菌抗生素Scopafungin同质,为36元环大环内酯类抗生素。S1对白色念珠菌(Candida albicans)、黑曲霉(Aspergillus niger)及红酵母(Rhodotorula sp.)均有抗菌活性,其MIC分别为0.234、0.469μg/mL和0.234μg/mL。     

A New Amino Acid Antibiotic KT–151, Produced by Streptomyces luteogriseus,Strain No. KT–151

From the results of taxonomic studies, Streptomyces sp. strain No. KT–151 isolated from a soil sample collected in Kumamoto City, was identified as a strain belonging to Streptomyces luteogriseus Schmitz, Deak, Crook and Hooper 1964. A new antibiotic, produced by this strain, was isolated as a leaflet crystal by ion-exchange chromatography and found to be an amino acid with the molecular formula, C₅H₁₂N₂O₂, and named antibiotic KT–151 (refered to as KT–151 hereinafter). The antibiotic showed antimicrobial activity against various Gram-positive and Gram-negative bacteria in a chemically defined medium but it was antagonized by several amino acids such as valine, leucine, isoleucine and threonine.     

两种水溶性抗菌活性物质的分离提取

对水溶性、不解离的极性物质分离时,一般采用吸附层析和凝胶层析等途径。实验通过硅胶柱层析、葡聚糖凝胶柱层析以及硅胶ＧＦ２５４制备型薄板层析,从发酵液样品中分离出两种有抗菌活性的纯物质。薄层层析的展开剂为二氯甲烷－四氢呋喃－甲醇－水（２５：３０：２）,分离出的组分中Ｒｆ＝０．７和Ｒｆ＝０．８两种物质有抗菌活性。硅胶柱层析洗脱过程为梯度洗脱,先用１５０ｍｌ上述展开剂洗脱,再用二氯甲烷－甲醇（２０：８０）     

Interaction of gramicidins with the cellular phospholipids of the producer Bacillus brevis

Phospholipid fractions were isolated from the cells of Bacillus brevis var. G.-B. variants, some, of which produced gramicidin S and some did not. As was found by thin layer chromatography, phosphatidyl ethanolamine predominated in the fraction of phospholipids. Interaction of the isolated phospholipids with gramicidin S in vitro resulted in a loss of the antibiotic activity. Presumably, formation of a complex between the polypeptide and phospholipids may decrease the actual concentration of gramicidin S in cells producing the antibiotic.     

Kosinostatin, a major secondary metabolite isolated from the culture filtrate of Streptomyces violaceusniger strain HAL64

During a screening program, an actinomycete strain isolated from the Egyptian soil was investigated for its potential to show antimicrobial activity. The identification of this isolate was performed according to spore morphology and cell wall chemo-type, which suggested that this strain is a streptomycete. Further cultural, physiological characteristics and the analysis of the nucleotide sequence of the 16S rRNA gene (1480 bp) of this isolate indicated that this strain is identical to Streptomyces violaceusniger (accession number EF063682) and then designated S. violaceusniger strain HAL64. In its culture supernatant, this organism could produce one major compound strongly inhibits the growth of Gram-positive but the inhibition of Gram-negative indicator bacteria was lower. The antibiotic was separated by silica gel column chromatography and then purified on a sephadex LH-20 column and finally the purity was checked by HPLC. The chemical structure of the purified compound was determined using spectroscopic analyses (molecular formula of C33H32N2O10 and molecular weight of 617.21) and found to be identical to the kosinostatin, a quinocycline antibiotic which is known to be produced by Micromonspora sp. TP-A0468 (Igarashi et al., 2002) and to quinocycline B isolated from Streptomyces aureofaciens (Celmer et al., 1958). Although the antibiotic is known, the newly isolated strain was able to produce the antibiotic as a major product providing an important biotechnological downstream advantage.     

Microbial Transformation of Antibiotics

Microbial transformation of the nucleoside analogue antibiotic showdomycin was performed using some Streptomyces species. Both the growing culture and the resting cells of Streptomyces sp. No. 383 arrested the antibacterial activity of showdomycin. The inactivated showdomycin was isolated from the reaction mixture by carbon chromatography and was identified with an isoshowdomycin sample which has been chemically derived from showdomycin. It is conjectured that the conversion of showdomycin to isoshowdomycin results from isomerization by an enzyme of Streptomyces sp. No. 383.     

Isolation of bacilysin and a new amino acid from culture filtrates of Bacillus subtilis

1. Bacilysin, a labile dipeptide antibiotic that lyses growing staphylococci, was isolated from culture fluids of Bacillus subtilis by a process giving higher yields than those previously obtained. 2. The process involves adsorption on a cation-exchange resin and elution with aqueous trimethylamine, separation from neutral amino acids and glutamic acid by chromatography on DEAE-Sephadex at pH8.7 and separation from other neutral peptides by chromatography in aqueous propan-2-ol on Sephadex G-25. 3. A new amino acid, which is chemically related to bacilysin, was isolated from the fraction containing neutral amino acids. 4. Two substances that yield alanine on hydrolysis, in addition to bacilysin, were obtained from the neutral peptide fraction.     

Quantitative estimate of unlabelled cordycepin in acid-soluble pool isolated from rat brain tissue after intraperitoneal injection of the inhibitor

A technique for the quantitative estimation of intraperitoneally injected unlabelled cordycepin in an acid-soluble (ASP) isolated from rat brain tissue is suggested. It consists in consecutive chromatography of ASP on Dowex 1×8, Dihydrpxyboryl=SP500 and Sephasorb-HP. The fraction containing 2′-deoxyriboadenosine and 3′-deoxyriboadenosine (cordycepin) has been isolated from brain tissue ASP of experimental animals after a cordycepin injection. 2′-Deoxyriboadenosine fraction has been isolated from tissue ASP of the control animals not subjected to an inhibitor injection. Brain tissues antibiotic content has been estimated by the difference in nucleoside quantity values (μM) in these two fractions (control/experiment).     

番茄溃疡病菌拮抗菌株Z-L-22的鉴定及其活性物质

摘要：【目的】鉴定一株对番茄溃疡病病原菌—密执安棒形杆菌密执安亚种(Clavibacter michiganensis subsp. michiganensis,Cmm)具有强拮抗作用的放线菌菌株Z-L-22,并分析其代谢产物,为开发新的生物活性物质奠定基础。【方法】根据菌株Z-L-22的形态特征、培养特征、生理生化特征、细胞壁组分和16S rDNA序列对菌株Z-L-22的进行了鉴定。通过薄层层析、纸层析和特征性鉴别试验对活性物质进行分离、回收和鉴定。并利用抗生素合成基因保守区域设计的引物用对基因组DNA进行PCR扩增。【结果】菌株Z-L-22属于链霉菌属,各特征与西唐链霉菌(Streptomyces setonii)相似。获得了2个主要活性成分,均为放线菌素类抗生素。利用放线菌素类抗生素合成酶保守引物在该菌基因组中扩增到770 bp的相关基因片段。【结论】活性菌株Z-L-22鉴定为西唐链霉菌,命名为西唐链霉菌Z-L-22。该菌产生的抗生活性物质为放线菌素类抗生素,本研究为开发该菌株奠定基础。