HIV-1 integrase is a critical enzyme for replication of HIV, and its inhibition is one of the most promising new drug strategies for anti-retroviral therapy, with potentially significant advantages over existing therapies. In this report, a series of HIV-1 inhibitors isolated from the organic extract of fermentations from terrestrial fungi is described. These fungal species, belonging to a variety of genera, were collected from throughout the world following the strict guidelines of Rio Convention on Biodiversity. The polyketide- and terpenoid-derived inhibitors are represented by two naphthoquinones, a biphenyl and two triphenyls, a benzophenone, four aromatics with or without catechol units, a linear aliphatic terpenoid, a diterpenoid, and a sesterterpenoid. These compounds inhibited the coupled and strand-transfer reaction of HIV-1 integrase with an IC(50) value of 0.5-120 micro M. The bioassay-directed isolation, structure elucidation, and HIV-1 inhibitory activity of these compounds are described.
The stimulation of human blood with a Ca2+ ionophore, A23187, leads to activation of polymorphonuclear leucocytes (PMN) with release of small amounts of catalyticaly active elastase, as demonstrated by the formation of a characteristic product, the N-terminal A alpha (1-21) peptide of the Aa subunit of fibrinogen. The identity of the peptide was initially established by radioimmunoassay (r.i.a.) with an antibody raised to A alpha (1-21). We now provide independent confirmation of the formation of A alpha (1-21) by fast-atom-bombardment-m.s. analysis of the fractions separated chromatographically after spiking of plasma samples with peptide labelled with [2H8]Phe at position 8. Identity of the peptides was established on the basis of their chromatographic retention time and by the distinct peaks in the mass spectra of these fractions. The relative intensities of the molecular ions of natural and labelled peptides were measured. On the basis of a comparison of the peaks of similar intensities, the concentration of the natural peptide at the time of spiking was close (79%) to the amount obtained by r.i.a. An additional peptide, des-alanyl-A alpha (2-21), was also seen. The total amount of material measured by r.i.a. could be accounted for by the sum of these two provides. The addition of label and assay by m.s. has provided an independent physical-chemical method for identifying A alpha (1-21) as a characteristic product of PMN elastase release in whole blood, but which is absent in freshly drawn blood.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.