A seminal study of soluble adenylyl cyclase

The functional property of egg yolk phosvitin as a melanogenesis inhibitor

Phosvitin is a phosphoglycoprotein present in egg yolk. More than half of the amino acids in phosvitin molecule are serine, of which >90% are phosphorylated. Therefore, phosvitin has a strong metal binding capability. The aim of this study was to investigate the effect of phosvitin on the inhibition of melanogenesis in melanoma cells. The results showed that phosvitin inhibited the activity of mushroom tyrosinase. Addition of phosvitin at a concentration of 50μg/ml, to B16F10 melanoma cells inhibited tyrosinase activity by approximately 42% and melanin synthesis by 17% compared to those in a control without phosvitin. Phosvitin inhibited the expression of tyrosinase, tyrosinase-related protein 1 (TRP-1), TRP-2, and microphthalmia-associated transcription factor (MITF) in B16F10 melanoma cells. In addition, phosvitin reduced the cellular cAMP concentration in B16F10 melanoma cells. These results indicate that phosvitin has the potential to be used as a melanogenesis inhibitor in the food and cosmetics industry.

A conformational transition in the adenylyl cyclase catalytic site yields different binding modes for ribosyl-modified and unmodified nucleotide inhibitors

Adenylyl cyclases (ACs) are promising pharmacological targets for treating heart failure, cancer, and psychosis. Ribose-substituted nucleotides have been reported as a potent family of AC inhibitors. In silico analysis of the docked conformers of such nucleotides in AC permits assembly of a consistent, intuitive QSAR model with strong correlation relative to measured pK(i) values. Energy decomposition suggests that the MANT group effects an AC conformational transition upon ligand binding.