Electronic coupling of the phycobilisome with the orange carotenoid protein and fluorescence quenching.

Using computational modeling and known 3D structure of proteins, we arrived at a rational spatial model of the orange carotenoid protein (OCP) and phycobilisome (PBS) interaction in the non-photochemical fluorescence quenching. The site of interaction is formed by the central cavity of the OCP monomer in the capacity of a keyhole to the characteristic external tip of the phycobilin-containing domain (PB) and folded loop of the core-membrane linker LCM within the PBS core. The same central protein cavity was shown to be also the site of the OCP and fluorescence recovery protein (FRP) interaction.

Thermodynamic and structural properties of tuber starches from transgenic potato plants grown in vitro and in vivo.

Potato plants harboring Phytochrome B (PHYB) gene from Arabidopsis thaliana or rol genes from Agrobacterium rhizogenes were used to study the effect of transgene expression on structure and properties of starch in tubers. Thermodynamic characteristics of starch (melting temperature, enthalpy of melting, thickness of crystalline lamellae) were shown to be variable depending on the transgene expression and plant culturing mode: in vitro or in soil. The expression of rolB or rolC genes in in vitro cultured plants evoked opposite effects on starch melting temperature and crystalline lamellae thickness.

The Na+-translocating ATPase in the plasma membrane of the marine microalga Tetraselmis viridis catalyzes Na+/H+ exchange.

Our previous investigations have established that Na+ translocation across the Tetraselmis viridis plasma membrane (PM) mediated by the primary ATP-driven Na+-pump, Na+-ATPase, is accompanied by H+ counter-transport [Y.V. Balnokin et al.

Ethylene rapidly up-regulates the activities of both monomeric GTP-binding proteins and protein kinase(s) in epicotyls of pea.

It is demonstrated that, in etiolated pea (Pisum sativum) epicotyls, ethylene affects the activation of both monomeric GTP-binding proteins (monomeric G-proteins) and protein kinases. For monomeric G-proteins, the effect may be a rapid (2 min) and bimodal up-regulation, a transiently unimodal activation, or a transient down-regulation. Pretreatment with 1-methylcyclopropene abolishes the response to ethylene overall.