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Shikimic acid antibiotics

In addition to acetyl-CoA, shikimic acid, mevalonic acid, and deoxyxylulose phosphate, other building blocks based on amino acids are frequently employed in natural product synthesis. Peptides, proteins, alkaloids, and many antibiotics are derived from amino acids, and the origins of the most important amino acid components of these are briefly indicated in Figure 2.1. Intermediates from the glycolytic pathway and the Krebs cycle are used in constructing many of them, but the aromatic amino acids phenylalanine, tyrosine,... [Pg.9]

Shikimic acid (144), or a close relative, has been deduced to be the source of a C7N unit (shown with heavy bonding) common to the antibiotics mitomycin (147)128 129 and rifamycin S (148) 129-131 a similar unit is also apparent in strep-tovaricin D (149). Shikimic acid is a proven precursor for bacterial phenazines which are arguably constructed from two related C7N units132 (for further research on these metabolites, see below). [Pg.31]

Exploration of geldanomycin (150) biosynthesis with D-[6-13C]glucose has revealed that the C7N unit of this antibiotic has a similar origin (labelling of C-17 and C-21 cf. nybomycin above), although shikimic acid (144) itself was a poor precursor.133 Similar observations were made on shikimic acid incorporation in the... [Pg.31]

The biosynthesis of ketomycin (128) ( -3-cyclohexenylglyoxylic acid) was studied using D-[C/- C]shikimic acid and D,L-[l,6- C2]shikimic acid, and it was found that the cyclohexenyl moiety of this antibiotic was derived from shikimic acid (119), and that 1 and 2 -C of ketomycin (128) were derived from carbon-1 and carbon-6 of 119 (Fig. 16) [211]. [Pg.93]

An ansamycin antibiotic produced by Streptomyces spectabilis with antibacterial (against tuberculosis pathogens), antiviral, and antitumor activities. S. occurs as a multi-component mixture of up to ten individual compounds (S. A to G, J, K, and U) with S. C (methyl streptovaricate, C4oH5,NO,4, Mr 769.84, amorphous, mp. 189-191 °C, [a][) 4-602°) as the main component. The S. are inhibitors of bacterial RNA-polyme-rase as well as the reverse transcriptase of oncogenic viruses. The biosynthesis of the aromatic core branches off from the shikimic acid pathway while the alkyl chain is formed on the polyketide pathway. [Pg.618]

The amino derivative 71 has been synthesized from shikimic acid to explore a new variant of the shikimate pathway which, leads to 3-amino-5-hydroxybenzoic acid, a proposed jnecursor of part of the ansamycin antibiotics. ... [Pg.198]

The biosynthesis of p-aminobenzoic acid, a structural component of the folic acid co-enzymes and of the antibiotic amicetin , is at present still under investigation and full details are not yet available . Weiss and Srinivasan showed that p-aminobenzoic acid (73) was formed by cell free extracts of baker s yeast from L-glutamine and shikimic acid-3-phosphate and that the amide group was the precursor of the aryl amino group in (73). In later work, cell free extracts of Aerobacter aerogenes 62-1 were found... [Pg.105]

The first reported study on the biosynthesis of nocardicin A was by Hosoda etal, who administered a variety of C-labelled compounds to shaken fermentations of Nocardia miformis subsp. tsuyamonensis 206). Examination of the resulting nocardicin A showed that L-[U- C]-tyrosine, [G- CJ-shikimic acid, and L-[U- C]-serine were all incorporated into the antibiotic. [U- C]-Glycine and L-[U- C]-homoserine were also incorporated but to a lesser degree, whereas the labels from L-[l- C]-tyrosine, L-[U- C]-phenylalanine, L-[U- C]-alanine and DL-[U- C]-a-amino-butyric acid were not incorporated to any significant extent. [Pg.51]

Lack of Repression of the Shildmic Acid Pathway.—It is well established that a control mechanism on the shikimic acid pathway is by repression of enzymes early in the pathway by the end products, e.g. by phenylalanine. Cases where this type of control appear to have broken down have now been reported. Lowe and Westlake, in studying the biosynthesis of the phenolic antibiotic chloramphenicol in Streptomyces sp. 3022a, examined several enzymes of the pathway, notably chorismate mutase and anthranilate synthetase, but could find no evidence that end-product control on chloramphenicol synthesis was operating in this organism. Similarly, Chu and Widholm fed phenylalanine and tyrosine to a range of tissue cultures of higher plants, but were not able to observe any evidence of feedback control on chorismate mutase levels. [Pg.217]

The syntheses of [5- H] labelled 5-epishikimic acid and [6 H] labelled shikimic acid have been achieved from L-shikimic acid. The synthesis of several deuterated and "C derivatives of shikimic acid has been described in order to study the biosynthesis of ansatrienin (a member of the ansamycin antibiotics). These derivatives were also used in feeding experiments to determine the biosynthesis of the cyclohexanecarboxylic acid starter unit of ca-cyclohexyl fatty acids in Alicyclobacillus acidocaldarius. ... [Pg.217]

Additional feeding using p- C,7a- C-tryptophan, COOH-anthra-nilic acid, U- C-shikimic acid, and 2- C-pyruvic acid failed to implicate any known pathway in the formation of the quinoline portion of streptonigrin 41, 42). Suspicions that a new pathway for quinoline biosynthesis was involved have recently been confirmed and the basic features of the biosynthesis of this portion of streptonigrin have been determined by analysis of the NMR spectrum of the antibiotic derived from feeding UL- Ce-D-glucose (35) to S. flocculus (7, 47). [Pg.94]

The Shikimate pathway is responsible for biosynthesis of aromatic amino acids in bacteria, fungi and plants [28], and the absence of this pathway in mammals makes it an interesting target for designing novel antibiotics, fungicides and herbicides. After the production of chorismate the pathway branches and, via specific internal pathways, the chorismate intermediate is converted to the three aromatic amino acids, in addition to a number of other aromatic compounds [29], The enzyme chorismate mutase (CM) is a key enzyme responsible for the Claisen rearrangement of chorismate to prephenate (Scheme 1-1), the first step in the branch that ultimately leads to production of tyrosine and phenylalanine. [Pg.4]

The shikimate biosynthetic pathway occurs in bacteria, plants, and fungi (including yeasts) and is a major entry into the biosynthesis of primary and secondary metabolites, for example aromatic amino acids, menaquinones, vitamins, and antibiotics [1], Starting from erythrose-4-phosphate (E4P) and phosphoenol-pyruvate... [Pg.511]

An mCyN unit is also present in the core of the polyketide antibiotic asukamycin from Streptomyces nodosas subsp. asukaensis [96]. This has been shown to arise not from a variant of the shikimate pathway, but from the condensation of a C4 unit from the TCA cycle, closely related to succinate, with a C3 unit, possibly dihydroxyacetone phosphate, from the triose pool. Related studies concerning 3-amino-4-hydroxybenzoic acid biosynthesis in Streptomyces murayamaensis mutants MC2 and MC3 support this hypothesis [97]. [Pg.81]

Chorismate synthase (CS) catalyzes the formation of chorismate, the last step in the shikimate pathway. Chorismate is a branch-point metabolite used for the synthesis of aromatic amino acids, p-aminobenzoic acid, folate, and other cyclic metabolites such as ubiquinone. The shikimate pathway is found only in plants, fungi, and bacteria, making the enzymes of the pathway potential targets for herbicides, antifungals, and antibiotics. [Pg.90]


See other pages where Shikimic acid antibiotics is mentioned: [Pg.77]    [Pg.8]    [Pg.22]    [Pg.298]    [Pg.318]    [Pg.424]    [Pg.445]    [Pg.2]    [Pg.93]    [Pg.147]    [Pg.156]    [Pg.39]    [Pg.46]    [Pg.181]    [Pg.111]    [Pg.99]    [Pg.232]    [Pg.113]    [Pg.31]    [Pg.29]    [Pg.37]    [Pg.114]    [Pg.138]    [Pg.471]    [Pg.1421]    [Pg.573]    [Pg.398]    [Pg.405]    [Pg.671]    [Pg.671]   
See also in sourсe #XX -- [ Pg.11 , Pg.182 , Pg.183 , Pg.184 , Pg.185 , Pg.186 , Pg.187 , Pg.188 , Pg.189 , Pg.190 ]

See also in sourсe #XX -- [ Pg.11 , Pg.182 , Pg.183 , Pg.184 , Pg.185 , Pg.186 , Pg.187 , Pg.188 , Pg.189 , Pg.190 ]




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Antibiotics shikimic acid derive

Antibiotics shikimic acid derived

Shikimate

Shikimic

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