Approximate calculation and experimental derivation of native isoelectric points of membrane protein complexes of Arabidopsis chloroplasts and mitochondria.

Electric charges are important intrinsic properties of proteins. They directly affect functionality and also mediate interactions with other molecules such as cofactors, substrates and regulators of enzymatic activity, with lipids as well as other proteins. As such, analysis of the electric properties of proteins gives rise to improved understanding of the mechanism by which proteins fulfil their specific functions.

Resolution of adiponectin oligomers in human plasma using free flow electrophoresis.

Adiponectin is an important adipocytokine hormone which circulates in blood as homo-oligomers (trimer, hexamer and high molecular weight (HMW) forms) as well as a truncated form corresponding to the globular domain. Free flow electrophoresis (FFE) used in zone electrophoresis mode revealed the presence of isoforms within these oligomeric forms in plasma. HMW adiponectin oligomer showed two isoforms which carry different charge density at pH 4.

Functional characterization of BbCRASP-2, a distinct outer membrane protein of Borrelia burgdorferi that binds host complement regulators factor H and FHL-1.

Borrelia burgdorferi, the aetiological agent of Lyme disease, employs sophisticated means to survive in diverse mammalian hosts. Recent studies demonstrated that acquisition of complement regulators factor H and factor H-like protein-1 (FHL-1) allows spirochetes to resist complement-mediated killing. Serum-resistant B.

Targeted mutagenesis of the farnesylation site of Drosophila Ggammae disrupts membrane association of the G protein betagamma complex and affects the light sensitivity of the visual system.

Activation of phototransduction in the compound eye of Drosophila is mediated by a heterotrimeric G protein that couples to the effector enzyme phospholipase Cbeta. The gamma subunit of this G protein (Ggammae) as well as gamma subunits of vertebrate transducins contain a carboxyl-terminal CAAX motif (C, cysteine; A, aliphatic amino acid; X, any amino acid) with a consensus sequence for protein farnesylation. To examine the function of Ggammae farnesylation, we mutated the farnesylation site and overexpressed the mutated Ggammae in Drosophila.

Immunological characterization of the complement regulator factor H-binding CRASP and Erp proteins of Borrelia burgdorferi.

Complement activation plays an important role in the elimination of invading microorganisms. Borrelia (B.) burgdorferi sensu lato the etiological agent of Lyme borreliosis, can resist complement-mediated killing.

A chloroplast RNA binding protein from stromal thylakoid membranes specifically binds to the 5' untranslated region of the psbA mRNA.

The intrachloroplastic localization of post-transcriptional gene expression steps represents one key determinant for the regulation of chloroplast development. We have characterized an RNA binding protein of 63 kDa (RBP63) from Chlamydomonas reinhardtii chloroplasts, which cofractionates with stromal thylakoid membranes. Solubility properties suggest that RBP63 is a peripheral membrane protein.