Streptomyces noursei

Streptomyces mycarofaciens Midecamycin Streptomyces nodosus Amphotericin B Streptomyces noursei Nystatin... 

Antibiotics, e.g. Benzylpenicillin Gentamicin Nystatin Penicillin notatum, P. chrysogenum Micromonospora purpurea Streptomyces noursei Antibacterial drug Antibacterial drug Antifungal drug... 

It is obtained from Streptomyces noursei. It has similar antifungal action as amphotericin but is highly toxic and used topically only. It is effective against Candida, Histoplasma, Trichophyton, Blastomyces, Microsporum audouini etc. It is indicated in Candida albicans especially oral moniliasis. 

Nystatin is a mixture of tetraene antifungals produced by cultures of Streptomyces noursei. The principal component is nystatin Ai (Figure 3.68), but the commercial material also contains nystatin A2 and A3, which have additional glycoside residues. Nystatin is too toxic for intravenous use, but has value for oral treatment of intestinal candidiasis, as lozenges for oral infections, and as creams for topical control of Candida species. 

Nedal A, Sletta H, Brautaset T et al (2007) Analysis of the mycosamine biosynthesis and attachment genes in the nystatin biosynthetic gene cluster of Streptomyces noursei ATCC11455. Appl Environ Microbiol 73 7400-7407... 

A mixture of antifungal polyenes produced by the growth of certain strains of Streptomyces noursei, or by any other means. It consists largely of nystatin Aj. Approximate molecular formula C47H75NOi7 = 926.1. 

Streptomvces nodosus, 350 Streptomyces noursei, 829 Streptomyces orchidaceus, 504 Streptomyces onentalis, 1060 Streptomyces peuceticus, 575 Streptomycin, 976 Streptomycin sulphate, 976 Streptosil, 991... 

Nystatin Organic acids, e.g. Streptomyces noursei Antifungal drug... 

The antibiotic cycloheximide was isolated in 1946 from actinomycetes fungi producing streptomycin (Leach et al., 1947 Whiffen, 1948), and later was also produced from Streptomyces noursei fungi (Brown and Hazen, 1956). Naramycin A, isolated in Japan from Streptomyces naranensis fungi, is also cycloheximide (Okuda, 1959). Cycloheximide was first used in agriculture in 1948 under the name Actidione in the USA. Its chemical structure is 4 (2/ )-2-[(15,35,5S)-(3,5-dimethyl-... 

B. (2000). Biosynthesis of the polyene antifungal antibiotic nystatin in Streptomyces noursei ATCC 11455 Analysis of the gene cluster and deduction of the biosynthetic pathway. Chem. Biol. 7, 395 03. 

Nitrogen metabolism plays a critical role in the biosynthesis of the streptothricin-type antibiotic nourseothricin in Streptomyces noursei [102]. Glutamine synthetase is repressed in this organism by a high concentration of ammonium ions. After the ammonium ion is depleted from the medium, derepression of the enzyme occurs. O-aminobenzoic (anthranilic) acid stimulates nourseothricin production and has a marked effect on regulation of enzymes responsible for nitrogen metabolism [102]. 

In 1950, Hazen and Brown published a report [1] on a new antifungal substance called nystatin produced by Streptomyces noursei, representing the first example of a polyene macrolide. Thereafter a great number of natural substances with a similar structure [2-5] were discovered, mostly produced by soil Actinomycetes belonging to the genus Streptomyces [5]. The primary interest in these anti-... 

Nystatin Al, initially named fungicidin, is a polyene macrolide with a 38-membered macrolactone ring and was isolated in 1950 from Streptomyces noursei [127, 128], and patented in 1964 [129], The stmcture 146 was assigned to it by Borowski and coworkers in 1971, while the stereochemistry of the molecule was unraveled several years later (Figure 7.46) [130, 131], Nystatin is mainly used for topical treatment of candidiasis [132], and represents a commercial product with a world market estimated to be in the range of US 250-300 million per year. In spite the commercial interest, very limited reports have appeared on biosynthesis of nystatin. 

Pioduccd by Streptomyces noursei broad Spectrum antifungal antibi otic available in topical and oral formulatiorts used to treat candidiasis see Chapter 19. 

Nystatin, obtained from Streptomyces noursei, has the molecular formula C46H77O19N. Its ultraviolet absorption spectrum indicates that it contains a tetraene grouping. Amphotericin B, obtained from another species of Streptomyces, has the formula C46H73O20N and contains a heptaene group-ing " . Both antibiotics are amphoteric and both consist of C40 structures linked to an amino sugar named mycosamine. 

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