Disease relevance of Hydrophobicity

• Replacing the isoleucine at amino-acid position three of bacteriophage T4 lysozyme causes changes in the thermodynamic stability of the protein that are directly related to the hydrophobicity of the substituted residue [1].
• The ability of TNBS to decrease mucosal hydrophobicity and induce colitis was attenuated if the hapten was coupled with dipalmitoylphosphatidylcholine [2].
• These sequences, which resemble authentic presequences in their overall amino acid composition and degree of hydrophobicity, are rather frequent; greater than 2.7% of clones generated from E. coli DNA and greater than 5% of clones from the dihydrofolate reductase gene were functional in our screening system [3].
• Difficulties in obtaining adequate quantities of virions retaining env, as well as the unstable nature and hydrophobicity of the oligomer, may account for the absence of previous biophysical studies to determine the oligomeric valency of membrane-associated env [4].
• Mechanism of fusion of Sendai virus: role of hydrophobic interactions and mobility constraints of viral membrane proteins. Effects of polyethylene glycol [5].

High impact information on Hydrophobicity

• The solution structure of a CUE domain of the yeast Cue2 protein in complex with ubiquitin reveals intermolecular interactions involving conserved hydrophobic surfaces, including the Leu8-Ile44-Val70 patch on ubiquitin [6].
• Together with the TRAM protein, Sec61p provides a site in the membrane, at the interface of channel and lipid, through which a TM domain can dynamically equilibrate between the lipid and aqueous phases, depending on the hydrophobicity of the TM domain and the length of the polypeptide segment tethering it to the ribosome [7].
• Peptide binding is mediated by electrostatic interactions with the EEVD motif, with the C-terminal aspartate acting as a two-carboxylate anchor, and by hydrophobic interactions with residues upstream of EEVD [8].
• BID's activity is regulated by a Caspase 8-mediated cleavage event, exposing the BH3 domain and significantly changing the surface charge and hydrophobicity, resulting in a change of cellular localization [9].
• The tip of the FYVE domain has basic and hydrophobic surfaces positioned so that nonspecific interactions with the phospholipid bilayer can abet specific binding to phosphatidylinositol 3-phosphate [10].

Chemical compound and disease context of Hydrophobicity

• We demonstrated that IgG exposure to pro-oxidative ferrous ions or to reactive oxygen species enhances paratope flexibility and hydrophobicity, leading to expansion of the spectrum of recognized antigens, regulation of cell proliferation, and protection in experimental sepsis [11].
• The results indicate that signal peptide hydrophobicity can completely override possible requirements for negatively charged residues and strong beta-turn forming potential in the mature protein and that the polyleucine-containing signal peptide may act as a generic signal sequence for the transport of non-native proteins in E. coli [12].
• Mannose resistant adhesion to HEp-2 cells was determined for 124 isolates of E coli and surface hydrophobicity was estimated by salt agglutination in 96 of these isolates [13].
• RESULTS: Upon exposure, phage were inactivated (non-infective) at methanol, ethanol and 1-propanol concentrations inversely dependent upon alcohol hydrophobicity [14].
• At the same time or later the backbone torsions rearrange due to local tendency of the proline ring to form a turn: this step depends on solvation forces and is helped by loose hydrophobic interactions [15].

Biological context of Hydrophobicity

• Mucus triglyceride level was modestly increased with infection, but mucus phospholipids or lipolysis were unrelated to H. pylori and hydrophobicity [16].
• DNA sequence analysis reveals a 32-kD protein with no obvious NH2-terminal signal sequence but with two domains of sufficient length and hydrophobicity to span a lipid bilayer [17].
• Structure-guided mutagenesis followed by in vitro binding and in vivo colocalization assays demonstrate that a hydrophobic interaction formed by Phe 330 of gephyrin and Phe 398 and Ile 400 of the GlyR beta-loop is crucial for binding [18].
• Prenylation and palmitoylation of a COOH-terminal cluster of three cysteine residues confers hydrophobicity and membrane association to paralemmin [19].
• Since the amino acid sequences for several muscarinic and adrenergic receptors are known, an attempt was made to correlate side chain hydrophobicity surrounding the aspartate anionic groups with binding structure-activity relationships [20].

Anatomical context of Hydrophobicity

• Cholesterol gallstone disease is characterized by several events, including cholesterol precipitation in bile, increased bile salt hydrophobicity and gallbladder inflammation [21].
• The aim of this study was to investigate whether parenteral NSAIDs alter surface hydrophobicity of the gastroduodenal mucosa [22].
• Effect of 16,16-dimethyl prostaglandin E2 on the surface hydrophobicity of aspirin-treated canine gastric mucosa [23].
• Addition of 16,16-dimethyl prostaglandin E2 to the nutrient compartment of these chambers maintained surface hydrophobicity at control levels but did not prevent aspirin-induced reductions in potential difference or cellular damage to the surface epithelium [24].
• In the duodenum, mucosal prostaglandin synthesis was restored 24 hours after NSAID dosing, but hydrophobicity was still decreased [22].

Associations of Hydrophobicity with chemical compounds

• Since disruption of homophilic interactions between the bound molecules required the presence of Triton X-100, hydrophobic interactions may occur after the initial ionic binding [25].
• Hydrophobic interactions and an unusual main-chain carbonyl contact to a guanine account for sequence-specific recognition in the minor groove by this helix [26].
• The galactose moiety is oriented differently from ligands in the mannose-glucose specific legume lectins and is held by hydrophobic interactions with Ala88, Tyr106, Phe131, and Ala218 and by seven hydrogen bonds, four of which are to the conserved Asp89, Asn133, and NH of Gly107 [27].
• In pressinoic acid, the Tyr2 side chain is in the expected "pressor conformation," that is, extended away from the ring system, and is stabilized through a hydrophobic interaction with the Phe3 side chain [28].
• Experiments with the environment-sensitive fluorescent probe ANS (8-anilino-1-naphthalene-sulfonic acid) provided further evidence for a reversible structural transition at mildly acidic pH associated with an increase in exposed hydrophobicity in class II molecules [29].

Gene context of Hydrophobicity

• The crystal structure of the complex between VEGF and the second domain of Flt-1 shows domain 2 in a predominantly hydrophobic interaction with the "poles" of the VEGF dimer [30].
• The DNA in the complex contorts into an unusual S shape that juxtaposes PU.1 and IRF-4 for selective electrostatic and hydrophobic interactions across the central minor groove [31].
• The main interface involves the C-terminal tail of FEN1, which forms two beta-strands connected by a short helix, the betaA-alphaA-betaB motif, participating in beta-beta and hydrophobic interactions with PCNA [32].
• A conformational change may facilitate palmitoyl extrusion from BET3 and allow the fatty acid chain to engage in intermolecular hydrophobic interactions [33].
• Hydrophobic interactions and a network of salt bridges render VASP TD highly thermostable with a melting point of 120 degrees C [34].

Analytical, diagnostic and therapeutic context of Hydrophobicity

• Moreover, oral administration of bile from rats pretreated with parenteral NSAIDs significantly decreased mucosal hydrophobicity in untreated rats [22].
• The effect of temperature from 5 degrees C to 50 degrees C on the retention of dansyl derivatives of amino acids in hydrophobic interaction chromatography (HIC) was investigated by HPLC on three stationary phases [35].
• A comparison of multiple sequence alignments with hydrophobicity plots revealed that MaxiK channel alpha subunits have a unique hydrophobic segment (S0) at the N terminus [36].
• We purified (approximately 10,000-fold) from human plasma a vWF-degrading protease, using chelating Sepharose, hydrophobic interaction chromatography, and gel filtration [37].
• The active heparan sulfate proteoglycan can be partially purified by affinity chromatography on thrombospondin-agarose or hydrophobic interaction with octyl-Sepharose [38].

References