Aflatoxins from Aspergillus parasiticus

Substituted coumarins (aflatoxins), from Aspergillus flavus and A. parasiticus. 

McGuire, S. M., Silva, J. C., Casillas, E. G., Townsend, C. A., Purification and characterization of versicolorin B synthase from Aspergillus parasiticus. Catalysis of the stereo differentiating cyclization in aflatoxin biosynthesis essential to DNA interaction. Biochemistry 1906, 35, 11470-11486. 

BHATNAGAR, D., ULLAH, A.H.J., CLEVELAND, T.E., Purification and characterization of a methyltransferase from Aspergillus parasiticus SRRC 163 involved in aflatoxin bios5mthetic pathway. Prep. Biochem., 1988,18, 321-349. 

SILVA, J.C., MINTO, R.E., BARRY, C.E., HOLLAND, K.A., TOWNSEND, C.A., Isolation and characterization of the versicolorin B synthase gene from Aspergillus parasiticus Expansion of the aflatoxin B] biosynthetic cluster, J. Biol. Chem., 1996, 271, 13600-13608. 

CARY, J.W., DYER, J.M., EHRLICH, K.C., WRIGHT, M.S., LIANG, S.H., LINZ, J.E., Molecular and functional characterization of a second copy of the aflatoxin regulatory gene, aflR-2, from Aspergillus parasiticus, Biochim. Biophys. Acta., 2002, 1576, 316-323. 

YU, J CARY, J.W., BHATNAGAR, D CLEVELAND, T.E., KELLER, N.P., CHU, F.S., Cloning and characterization of a cDNA from Aspergillus parasiticus encoding an O-methyltransferase involved in aflatoxin biosynthesis, Appl. Environ. Microbiol., 1993,59,3564-3571. 

YU, J., CHANG, P.-K., PAYNE, G.A., CARY, J.W., BHATNAGAR, D., CLEVELAND, T.E., Comparison of the omtA genes encoding 0-methyltransferases involved in aflatoxin biosynthesis from Aspergillus parasiticus and A. flavus, Gene.,... 

Other naturally derived aflatoxin inhibitors obtained from the "neem" tree have been investigated in our laboratory (84), Azadirachta indica Juss. commonly known as "margosa" or "neem" is an ornamental tree of Asia and Africa that produces natural products having reputed value for their medicinal, antiviral, antibacterial, insecticidal, antifungal and antinematode properties (86, 87). Several active principles from different parts of the neem tree have been reported (88). Our investigation (84) examined the effects of these neem leaf components in neem leaves on aflatoxin biosynthesis by either Aspergillus parasiticus or A. flavus. 

C, (decomp.). Metabolite from Aspergillus species (A. versicolor, A. parasiticus, A. ustus, A. ni-dulans, A. multicolor), and phytopathogenic fungi (Cercospora smilacis, Dothistroma pini), and Mono-cillium nordinii. A. is an intermediate in aflatoxin biosynthesis and shows weak mutagenic activity in the Ames test. 

The optically active fungal metabolite sterigmatocystin (15) (Fig. 13.4, see also Sect. 13.2) was first isolated (but not structurally defined) from Aspergillus versicolor by Abou-Zeid in 1953 (590), and has been purified subsequently a number of times from this species (591-594) as well as the related A. parasiticus (595) and A. multicolor (596), and both Emericella venezuelensis (597) and Emericella astellata (598) (both of which also produced aflatoxins). 

---