Diversity and pharmaceutical screening of fungi from benthic mats of Antarctic lakes.

During the MICROMAT project, the fungal diversity of microbial mats growing in the benthic environment of Antarctic lakes was accessed for the discovery of novel antibiotics and anticancers. In all, 160 filamentous fungi belonging to fifteen different genera and 171 yeasts were isolated from 11 lakes, classified and cultivated in different media and at different temperatures. Filamentous fungi were then screened to discover novel antimicrobial and cytotoxic compounds.

Inhibitors of myo-inositol monophosphatase, ATCC 20928 factors A and C. Isolation, physico-chemical characterization and biological properties.

During the course of a screening program for inhibitors of myo-inositol monophosphatase we fermented the strain ATCC 20928, a known producer of L-671,776. We now show that this strain produces a complex of at least three sesquiterpenic compounds, L-671,776 (termed factor B) and two structurally related substances, termed factors A and C. Both factors A and C, like L-671,776, exhibited inhibitory activity against myo-inositol monophosphatase.

Cryptochrome, Phytochrome, and the Photoregulation of Anthocyanin Production under Blue Light.

The principle of equivalent light action predicts that two light treatments (wavelengths ;lambda(1) and lambda(2)) producing the same Pfr/P ratio (phi(lambda1) = phi(lambda2)) and the same rate of phytochrome photoconversion (k(lambda1) = k(lambda2)) are perceived by phytochrome as being the same and should produce the same effect. The results of experiments based on the principle of equivalent light action indicate that cryptochrome is involved in the photoregulation of anthocyanin production elicited by blue light in tomato seedlings. This was also the case for one strain of cabbage seedlings.