Fusidium coccineum

Fusidic acid is a product of, among others, the fungus Fusidium coccineum. It has a steroidal structure and has mainly bacteriostatic activity. Its mechanism of action is based on inhibition of bacterial protein synthesis. Its indications are limited to the treatment of severe staphylococcal infections, usually in combination with another antistaphylococcal agent to prevent the emergence of resistance. 

A number of triterpenoids are bioactive compounds and are used in medicine. For example, fusidic acid is an antimicrobial fungal metabolite, isolated from Fusidium coccineum, and cytotoxic dimeric triterpenoids, crellastatins, are isolated from marine sponges Crella species. 

Figure 8.29 Changes in total PolyP, pyrophosphate and ATP content in mycelium of Fusidium coccineum during growth of strains with high antibiotic (fusidium acid) productivity (-o-) and with low antibiotic productivity (- -) (Kulaev, 1986).

The finding169 that a 2-pro-S hydrogen from MVA was lost during the formation of fusidic acid (99) by the mould Fusidium coccineum may provide evidence for the intermediacy of a A20(22)-sterol (100) however, (99) biosynthesized from (3RS,2R )-[2-14C, 2-3H]MVA and its (2S)-isomer each contained an atom of tritium at C-22, a result which excludes the possibility of (100) as a precursor. 

Tricho-acorenol (143), isolated from a T. koningii, has been claimed to be a new compound [129]. It is in fact identical to coccinol previously isolated from Fusidium coccineum in 1968 [208, 209]. In describing the evidence for structure 143, the authors report that MnC>2 oxidation of gave acorenone B [129] which is diastereomeric at the spiro-carbon, according to the reference quoted by the authors [210]. Aspects of the biosynthesis of coccinol have been studied [209] and the more pertinent details are presented in Scheme 22. 

Fusidic Acid Fusidium coccineum Fusidic acid, antibacterial agent... 

Nine minor cometabolites (27)—(35) of the important antibiotic fusidic acid from the fungus Fusidium coccineum have been identified. Structure-activity relationships among fusidic acid type antibiotics have been reviewed.10a-Cucurbita-5,24-dien-3/3-ol (36) have been isolated from Lagenaria leucantha (Cucurbitaceae). The n.m.r. spectra of various cucurbitacins have been discussed. ... 

Protostane and their 29-nor-derivatives denoted as fusidanes are fimgal metabolites. Cephalosporium caerulens, for instance, produces (-l-)-protosta-17(20)-( -24-diene-3p-ol. Fusidanes sueh as helvolic acid from the Helvola mutant of the mold Aspergillus fumigatus and related structures are widely used as antibacterials. Fusi-dic acid isolated from the fermentation broth of Fusidium coccineum and related tribes is an example. Its sodium salt has immunosuppressive and antibacterial properties, and is applied in ointments against multiresistant staphylococci during the therapy of wound infections... 

I oduced by Fusidium coccineum active against coiynebacretia, coagulase-negative and positive st rhylococci. and strict anaer-obes-... 

Although fusidic acid, C3iH480g, a metabolite of Fusidium coccineum and Cephalosporium lamellaecola, has been known for many years, it is only recently that a complete structure (I) has been proposed for this antibiotic (Arigoni et al., 1964 Bucourt and Legrand, 1964). There is still room for doubt regarding some... 

Ebersole, R. C., W. O. Godtfredsen, S. Vangedal, and E. Caspi Mechanism of Oxidative Cyclization of Squalene. Concerning the Mode of Formation of the 17(20) Double Bond in the Biosynthesis of Fusidic Acid by Fusidium coccineum. J. Amer. Chem. Soc. 96, 6499 (1974). 

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