Contribution of lysine-containing cationic domains to thermally-induced phase transition of elastin-like proteins and their sensitivity to different stimuli.
A series of elastin-like proteins, SKGPG[V(VKG)(3)VKVPG](n)-(ELP1-90)WP (n = 1, 2, 3, and 4), were biosynthesized based on the hydrophobic and lysine linkage domains of tropoelastin. The formation of self-assembled hydrophobic aggregates was monitored in order to determine the influence of cationic segments on phase transition properties as well as the sensitivity to changes in salt and pH. The thermal transition profiles of the proteins fused with only one or two cationic blocks (n = 1 or 2) were similar to that of the counterpart ELP1-90. In contrast, diblock proteins that contain 3 and 4 cationic blocks displayed a triphasic profile and no transition, respectively. Upon increasing the salt concentration and pH, a stimulus-induced phase transition from a soluble conformation to an insoluble aggregate was observed. The effects of cationic segments on the stimuli sensitivity of cationic bimodal ELPs were interpreted in terms of their structural and molecular characteristics.
Laboratory of Biochemistry and Cellular Engineering, Daegu Gyeongbuk Institute of Science and Technology, Daegu, Korea. wbjeon@dgist.ac.kr
Won Bae
WB
Jeon
D000595:Amino Acid Sequence; D001704:Biopolymers / Q000737:chemistry* / Q000378:metabolism; D004549:Elastin / Q000737:chemistry / Q000378:metabolism; D016326:Extracellular Matrix Proteins / Q000737:chemistry* / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D057927:Hydrophobic and Hydrophilic Interactions; D008239:Lysine / Q000737:chemistry*; D008969:Molecular Sequence Data; D044367:Phase Transition; D017434:Protein Structure, Tertiary; D012492:Salts; D013696:Temperature; D014333:Tropoelastin / Q000737:chemistry / Q000378:metabolism
D001704:Biopolymers; D016326:Extracellular Matrix Proteins; D012492:Salts; D014333:Tropoelastin; D004549:Elastin; D008239:Lysine