Diverse Roles of Glycine Residues Conserved in Photoactive Yellow Proteins☆ Export

@article{citeulike:6016926, abstract = {The role of glycine residues was studied by alanine-scanning mutagenesis using photoactive yellow protein, a structural prototype of PER ARNT SIM domain proteins, as a template. Mutation of glycine located close to the end of β -strands with dihedral angles disallowed for alanine (Gly-37, Gly-59, Gly-86, and Gly-115) induces destabilization of the protein structure. On the other hand, substitution for Gly-77 and Gly-82, incorporated into the fifth α -helix, slows the photocycle by 15–20 times, suggesting that these residues regulate the light-induced structural switch between dark-state structure and signaling-state structure. Most importantly, a significant amount of G29A is in the bleached state and showed a 1000-fold slower photocycle. As O 2 of the carboxylic acid of Glu-46 is close enough for contact with C α of Gly-29, alanine mutation perturbs this packing. Fourier transform infrared spectroscopy demonstrated that the C O 2 stretching mode of Glu-46 is 6 cm −1 upshifted in G29A, suggesting that C α of Gly-29 acts as a proton donor for the C α -H…O 2 hydrogen bond with Glu-46, which stabilizes the dark-state structure. During the photocycle, Glu-46 becomes negatively charged by donating a proton to the chromophore, resulting in breakage of this hydrophobic packing and consequent conformational change of the protein.}, author = {Imamoto, Yasushi and Tatsumi, Sanae and Harigai, Miki and Yamazaki, Yoichi and Kamikubo, Hironari and Kataoka, Mikio}, citeulike-article-id = {6016926}, citeulike-linkout-0 = {http://dx.doi.org/10.1529/biophysj.107.123414}, citeulike-linkout-1 = {http://linkinghub.elsevier.com/retrieve/pii/S0006349508704387}, day = {01}, doi = {10.1529/biophysj.107.123414}, issn = {00063495}, journal = {Biophysical Journal}, keywords = {alanine, conserved, glycine, mutation, omamo08pdf}, month = {May}, number = {9}, pages = {3620--3628}, posted-at = {2009-10-27 22:14:01}, priority = {2}, title = {Diverse Roles of Glycine Residues Conserved in Photoactive Yellow Proteins☆}, url = {http://dx.doi.org/10.1529/biophysj.107.123414}, volume = {94}, year = {2008} }

TY - JOUR ID - citeulike:6016926 L3 - citeulike-article-id:6016926 N2 - The role of glycine residues was studied by alanine-scanning mutagenesis using photoactive yellow protein, a structural prototype of PER ARNT SIM domain proteins, as a template. Mutation of glycine located close to the end of β -strands with dihedral angles disallowed for alanine (Gly-37, Gly-59, Gly-86, and Gly-115) induces destabilization of the protein structure. On the other hand, substitution for Gly-77 and Gly-82, incorporated into the fifth α -helix, slows the photocycle by 15–20 times, suggesting that these residues regulate the light-induced structural switch between dark-state structure and signaling-state structure. Most importantly, a significant amount of G29A is in the bleached state and showed a 1000-fold slower photocycle. As O 2 of the carboxylic acid of Glu-46 is close enough for contact with C α of Gly-29, alanine mutation perturbs this packing. Fourier transform infrared spectroscopy demonstrated that the C O 2 stretching mode of Glu-46 is 6 cm −1 upshifted in G29A, suggesting that C α of Gly-29 acts as a proton donor for the C α -H…O 2 hydrogen bond with Glu-46, which stabilizes the dark-state structure. During the photocycle, Glu-46 becomes negatively charged by donating a proton to the chromophore, resulting in breakage of this hydrophobic packing and consequent conformational change of the protein. IS - 9 JF - Biophysical Journal SN - 00063495 EP - 3628 TI - Diverse Roles of Glycine Residues Conserved in Photoactive Yellow Proteins☆ VL - 94 SP - 3620 KW - alanine KW - conserved KW - glycine KW - mutation KW - omamo08pdf AU - Imamoto, Yasushi AU - Tatsumi, Sanae AU - Harigai, Miki AU - Yamazaki, Yoichi AU - Kamikubo, Hironari AU - Kataoka, Mikio PY - 2008/05/01/ UR - http://dx.doi.org/10.1529/biophysj.107.123414 ER -