skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: There and Back Again: Loss and Reacquisition of Two-Cys Photocycles in Cyanobacteriochromes

 [1];  [1];  [1]
  1. Department of Molecular and Cellular Biology, University of California, Davis CA
Publication Date:
Sponsoring Org.:
OSTI Identifier:
Grant/Contract Number:
DOE DE-SC0002395
Resource Type:
Journal Article: Publisher's Accepted Manuscript
Journal Name:
Photochemistry and Photobiology
Additional Journal Information:
Journal Volume: 93; Journal Issue: 3; Related Information: CHORUS Timestamp: 2017-10-20 17:36:51; Journal ID: ISSN 0031-8655
Country of Publication:
United Kingdom

Citation Formats

Rockwell, Nathan C., Martin, Shelley S., and Lagarias, John Clark. There and Back Again: Loss and Reacquisition of Two-Cys Photocycles in Cyanobacteriochromes. United Kingdom: N. p., 2017. Web. doi:10.1111/php.12708.
Rockwell, Nathan C., Martin, Shelley S., & Lagarias, John Clark. There and Back Again: Loss and Reacquisition of Two-Cys Photocycles in Cyanobacteriochromes. United Kingdom. doi:10.1111/php.12708.
Rockwell, Nathan C., Martin, Shelley S., and Lagarias, John Clark. Sat . "There and Back Again: Loss and Reacquisition of Two-Cys Photocycles in Cyanobacteriochromes". United Kingdom. doi:10.1111/php.12708.
title = {There and Back Again: Loss and Reacquisition of Two-Cys Photocycles in Cyanobacteriochromes},
author = {Rockwell, Nathan C. and Martin, Shelley S. and Lagarias, John Clark},
abstractNote = {},
doi = {10.1111/php.12708},
journal = {Photochemistry and Photobiology},
number = 3,
volume = 93,
place = {United Kingdom},
year = {Sat May 13 00:00:00 EDT 2017},
month = {Sat May 13 00:00:00 EDT 2017}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record at 10.1111/php.12708

Citation Metrics:
Cited by: 4works
Citation information provided by
Web of Science

Save / Share:
  • The phytochrome superfamily encompasses a diverse collection of photochromic photoreceptors in plants and microorganisms that employ a covalently linked bilin cradled in a cGMP-phosphodiesterase/adenylyl-cyclase/FhlA (GAF) domain to detect light. Whereas most interconvert between red- and far-red-light-absorbing states, cyanobacteria also express variants called cyanobacteriochromes (CBCRs) that modify bilin absorption to collectively perceive the entire visible spectrum. Here, we present two X-ray crystallographic structures of the GAF domain from the blue/green photochromic CBCR PixJ from Thermosynechococcus elongatus. Moreover, these structures confirm the hypothesis that CBCRs variably manipulate the chromophore π-conjugation system through isomerization and a second thioether linkage, in this case involvingmore » the bilin C10 carbon and Cys494 within a DXCF sequence characteristic of blue/green CBCRs. Biochemical studies support a mechanism for photoconversion whereby the second linkage ruptures on route to the green-light-absorbing state. All together, theTePixJ(GAF) models illustrate the remarkable structural and photochemical versatility among phytochromes and CBCRs in driving light perception.« less
  • Most naturally occurring mutants of the retinoblastoma (RB) protein contain large deletions or truncations. The small cell lung carcinoma cell line H209 contains a normal-sized but unphosphorylated RB protein, which fails to form a complex with SV40 T antigen, suggesting that the RB gene of H209 may contain a subtle mutation. To define this mutation, the RB complementary DNA and genomic DNA were sequenced, revealing a point mutation in exon 21 that changed a G to a T. This results in an amino acid substitution of a Phe for Cys{sup 706}. The mutant RB complementary DNA was used as amore » template for in vitro transcription and translation to synthesize the mutated protein. The resulting protein failed to bind to SV40 T antigen, demonstrating that a single missense mutation of the RB gene led to the complete inactivation of the ability of the RB protein to bind T antigen.« less
  • On January 30 and February 11, 1985, the Environmental Protection Agency (EPA) canceled the use of 2,4,5-T and of silvex, a chemical analog of 2,4,5-T. These actions climaxed the most controversial and turbulent period in the history of forest pest management. Beginning in 1969, stories about 2,4,5-T safety generated intense social activism, litigation, and sometimes violence. Foresters, farmers, ranchers, politicians, manufacturers, environmentalists, scientists, regulatory officials, and local citizens entered the debate. The role of government in pesticide regulation and the integrity of industry and science were being challenged. Although 2,4,5-T and silvex are no longer used, questions remain. Were themore » ultimate decisions the result of scientific evidence and analysis, or were they a response to public opinion that with all the smoke there must be fire somewhere. Can forestry professionals help the nation avoid controversies of this nature in the future.« less
  • The Supreme Court rejected the proposition that a federal agency is required to assess the psychological health aspects of a federal project in Metropolitan Edison Co. v. People Against Nuclear Energy (PANE). The author challenges an earlier article by W. Jordan when he finds that the PANE decision establishes that the National Environmental Policy Act (NEPA) does not require this kind of assessment. After reviewing the PANE case, he concludes that Jordan was incorrect in suggesting that the Court's decision was narrow in scope and that psychological distress would be a cognizable environmental impact under NEPA in many cases. Themore » author agrees that psychological harm may well affect the quality of modern life, but it is not within the scope of NEPA.« less
  • Epithelial-mesenchymal transition (EMT) is a conversion that facilitates organ morphogenesis and tissue remodeling in physiological processes such as embryonic development and wound healing. A similar phenotypic conversion is also detected in fibrotic diseases and neoplasia, which is associated with disease progression. EMT in cancer epithelial cells often seems to be an incomplete and bi-directional process. In this Review, we discuss the phenomenon of EMT as it pertains to tumor development, focusing on exceptions to the commonly held rule that EMT promotes invasion and metastasis. We also highlight the role of the RAS-controlled signaling mediators, ERK1, ERK2 and PI3-kinase, as microenvironmentalmore » responsive regulators of EMT.« less