A New Antibiotic K-52B

A new antibiotic K-52B, different from K-52A, was isolated from the culture broth of Streptoverticillium roseoverticillatum subsp. albosporum, strain No. K-52. The antibiotic K-52B was thought to be a similar saccharide to K-52A from its physicochemical properties but differed from K-52A in the presence of nitrogen content. Antibiotic K-52B inhibited the growth of Gram-positive and Gram-negative bacteria, including Pseudomonas aeruginosa on a chemically defined medium. The growth inhibition was, however, reversed by l-glutamine, l-glutamic acid, l-asparagine and l-aspartic acid.     

Capoamycin,a New Isotetracenone Antibiotic

A new antibiotic was obtained from the cultured broth of an actinomycete identified as Streptomyces capoamus, and has been named capoamycin. The structure of capoamycin was elucidated by NMR spectral analysis and chemical degradation, which revealed that capoamycin was composed of a modified benz[a]anthraquinone chromophore, a β-C-olivoside and (E,E)-2,4- decadienoic acid. Capoamycin inhibited the growth of Gram-positive bacteria, yeasts and fungi, induced differentiation of mouse myeloid leukemia cells (M1) and prolonged the survival periods of mice bearing Ehrlich ascites carcinoma.     

Isolation and Structure Elucidation of a New Antifungal and Antibacterial Antibiotic Produced by Streptomyces sp. 201

An antibacterial and antifungal antibiotic was isolated from the culture filtrate of Streptomyces sp. 201, and its structure was determined as 2-methyl-heptyl isonicotinate by extensive use of NMR spectroscopy. The compound exhibited marked antimicrobial activity against Bacillus subtilis, Shigella sp., Klebsiella sp., E. coli, Proteus mirabilis, and the pathogenic fungi, Fusarium moniliforme, F. semitectum, F. oxysporum, F. solani and Rhizoctonia solani.     

Cephalexin, a New Orally Absorbed Cephalosporin Antibiotic

A new antibiotic, structurally related to cephaloglycin, has been assigned the generic name cephalexin, 7-(D-alpha-amino-alpha-phenylacetamido)-3-methyl-3-cephem-5-carboxylic acid. In vitro antimicrobial activity of cephalexin does not equal that of cephaloglycin. However, excellent oral absorption and lack of serum binding of cephalexin compensates significantly for the lower in vitro activity. Exceptional efficacy against experimental bacterial infections in mice was obtained with cephalexin therapy as compared with cephaloglycin, tetracycline, and chloramphenicol. The data suggest that cephalexin merits clinical trial.     

The Structure of an Antibiotic Kanamycin

The antibiotic kanamycin was degraded with methanolic hydrogen chloride and was determined to be composed of three compounds: deoxystreptamine, 6-amino-6-deoxy-d-glucopyranose and 3-amino-3-deoxy-d-glucopyranose. From the chemical and physical data on the antibiotic and its fragments, kanamycin was shown to be O-α-6-amino-6-deoxy-d-glucopyranosyl-(1→4 or 6)-O-[α-3-amino-3-deoxy-d-glucopyranosyl-(1→6 or 4)]-1,3-diamino-1, 2, 3-trideoxy-myo-inositol.     

新抗生素莫西沙星国内外研究应用最新进展

莫西沙星(moxifloxacin)属第四代氟喹诺酮类抗菌药物。莫西沙星通过抑制细菌的DNA螺旋酶A亚单位和拓扑异构酶IV的活性,阻断DNA的复制,从而发挥杀菌作用。对革兰阴性菌、阳性菌均有强大的抗菌能力,对支原体、衣原体、军团菌有效,对厌氧菌感染有效,尤其对某些临床常见的耐药菌有效。临床应用莫西沙星治疗社区获得性肺炎、急性细菌性鼻窦炎、泌尿生殖系感染、继发性腹膜炎、肺结核的早期及延长早期间治疗、强直性脊椎炎和皮肤、皮下组织感染的治疗。     

Clinical Evaluation of Adriamycin,a New Antitumour Antibiotic

Adriamycin, a new antitumour antibiotic of the anthracycline group with a structural formula very similar to daunorubicin, has proved to have potent tumour-growth-inhibiting properties, and to be particularly effective in childhood malignancies. Though adriamycin produces a higher percentage of side-effects than daunorubicin—namely, stomatitis and alopecia—a lower dosage may be used for therapy.     

Properties and Structure of a Novel Peptide Antibiotic No. 1907

There are three NAD biosynthetic pathways: the nicotinic acid-NAD, nicotinamide-NAD, and quinolinic acid (derived from tryptophan)-NAD pathways. To discover the main pathways of NAD biosyntheses in various tissues of the rat, the tissue distribution of nicotinamidase, quinolinate phosphoribosyltransferase, nicotinate phosphoribosyltransferase, nicotinamide phosphoribosyl-transferase, nicotinamide mononucleotide adenylyltransferase, and NAD⁺ synthetase were investigated. All of the tissues could synthesize NAD from nicotinamide, judging from that the activities of nicotinamide phosphoribosyltransferase and NMN adenylyltransferase detected in all of the tissues. From nicotinic acid, only liver, kidneys, and heart could. Liver and kidney can also synthesize NAD de novo from quinolinic acid.     

Isolation,Biological Properties,and Spatial Structure of Antibiotic Loloatin A

A peptide antibiotic with cyanolytic activity was isolated from the IGM52 strain of the Brevibacillus laterosporus Gram-positive spore-forming bacteria. By ¹H NMR spectroscopy, this antibiotic was identified as loloatin A, a cyclic decapeptide cyclo(-Asn-Asp-Tyr-Val-Orn-Leu-D-Tyr-Pro-Phe-D-Phe-). The spatial structure of loloatin A in solution was determined.     

New Antifungal Antibiotic,Polcillin

Polcillin was found in culture filtrate of Bacillus subtilis TPR-2201 isolated from a soil sample. By the purification it was obtained as white amorphous powder which was easily soluble in water, lower alcohol, wet acetone and pyridine. It is stable at pH values from 2.0 to 9.0. From the physicochemical studies it was found to be an acidic polypeptide consisting of such amino acids as aspartic acid, glutamic acid, serine, proline and tyrosine. The growth of fungi and yeasts are widely inhibited but most bacteria are not inhibited by above the concentration of 200 mcg/ml.