A systematic study of the effect of hydrophobicity and charge on the cell viability and cell association of lanthanide metal complexes is presented. The terbium luminescent probes feature a macrocyclic polyaminocarboxylate ligand (DOTA) in which the hydrophobicity of the antenna and that of the carboxyamide pendant arms are independently varied. Three sensitizing antennas were investigated in t...

In the present study, the hydrophobicity of a 26-residue α-helical peptide (peptide P) was altered to study the effects of peptide hydrophobicity on the mechanism of action of cationic anticancer peptides. Hydrophobicity of the nonpolar face of the peptides was shown to correlate with peptide helicity. The self-association ability of peptides in aqueous environment, determined by the reversed-p...

We have examined the hydrophobicity component of signal peptide function using polymeric sequences in combination with cassette mutagenesis. Using homopolymeric units of either isoleucine, leucine, valine or alanine to replace the natural core segment of the Escherichia coli alkaline phosphatase signal peptide, the hydrophobicity requirements for export and processing were delineated. The trans...

Changes in the cell surface properties of amoebae of Dictyostelium discoideum during growth in different culture conditions have been studied by aqueous two-phase partitioning on a thin-layer countercurrent distribution apparatus. Changes in cell surface properties were not dependent on the source of nutrients but only on cell density. There was a progressive increase in cell surface hydrophobi...

Upon growth on n-hexadecane (C(16)), n-tetracosane (C(24)), and n-hexatriacontane (C(36)), Dietzia sp. strain DQ12-45-1b could produce different glycolipids, phospholipids, and lipopeptides. Interestingly, cultivation with C(36) increased cell surface hydrophobic activity, which attenuated the negative effect of the decline of the emulsification activity. These results suggest that the mechanis...

Poly(arginine) mimics bearing long hydrophobic side chains adopt stable helical conformation and exhibit helix-related cell-penetrating properties. Elongating polypeptide backbone length and increasing side chain hydrophobicity further increase the helicities of poly(arginine) mimics. They show superior cell membrane permeability up to two orders of magnitude higher than that of HIV-TAT peptide...