Novel dimeric interface and electrostatic recognition in bacterial Cu,Zn superoxide dismutase

Eukaryotic Cu,Zn superoxide dismutases (CuZnSODs) are antioxidant enzymes remarkable for their unusually stable β-barrel fold and dimer assembly, diffusion-limited catalysis, and electrostatic guidance of their free radical substrate. Point mutations of CuZnSOD cause the fatal human neurodegenerative disease amyotrophic lateral sclerosis. We determined and analyzed the first crystallographic structure (to our knowledge) for CuZnSOD from a prokaryote, Photobacterium leiognathi, a luminescent symbiont of Leiognathid fish. This structure, exemplifying prokaryotic CuZnSODs, shares the active-site ligand geometry and the topology of the Greek key β-barrel common to the eukaryotic CuZnSODs. However, the β-barrel elements recruited to form the dimer interface, the strategy used to forge the channel for electrostatic recognition of superoxide radical, and the connectivity of the intrasubunit disulfide bond in P. leiognathi CuZnSOD are discrete and strikingly dissimilar from those highly conserved in eukaryotic CuZnSODs. This new CuZnSOD structure broadens our understanding of structural features necessary and sufficient for CuZnSOD activity, highlights a hitherto unrecognized adaptability of the Greek key β-barrel building block in evolution, and reveals that prokaryotic and eukaryotic enzymes diverged from one primordial CuZnSOD and then converged to distinct dimeric enzymes with electrostatic substrate guidance.

Photoactive yellow protein: A structural prototype for the three-dimensional fold of the PAS domain superfamily

PAS domains are found in diverse proteins throughout all three kingdoms of life, where they apparently function in sensing and signal transduction. Although a wealth of useful sequence and functional information has become recently available, these data have not been integrated into a three-dimensional (3D) framework. The very early evolutionary development and diverse functions of PAS domains have made sequence analysis and modeling of this protein superfamily challenging. Limited sequence similarities between the ∼50-residue PAS repeats and one region of the bacterial blue-light photosensor photoactive yellow protein (PYP), for which ground-state and light-activated crystallographic structures have been determined to high resolution, originally were identified in sequence searches using consensus sequence probes from PAS-containing proteins. Here, we found that by changing a few residues particular to PYP function, the modified PYP sequence probe also could select PAS protein sequences. By mapping a typical ∼150-residue PAS domain sequence onto the entire crystallographic structure of PYP, we show that the PAS sequence similarities and differences are consistent with a shared 3D fold (the PAS/PYP module) with obvious potential for a ligand-binding cavity. Thus, PYP appears to prototypically exhibit all the major structural and functional features characteristic of the PAS domain superfamily: the shared PAS/PYP modular domain fold of ∼125–150 residues, a sensor function often linked to ligand or cofactor (chromophore) binding, and signal transduction capability governed by heterodimeric assembly (to the downstream partner of PYP). This 3D PAS/PYP module provides a structural model to guide experimental testing of hypotheses regarding ligand-binding, dimerization, and signal transduction.

Roma antica /

Frontispiece port. of Nardini, v. 1, by L. Carlini. Illustrations new to this edition engraved by G. Acquaroni, G. Balzar, Giuseppe Mochetti and Angelo Testa, after drawings by Antonio de Romanis, Francesco Piranesi, Rosino, Angelo Uggeri, Giovanni Battista Vergani. Plates depicting coins by Carlo Ruspi.

Ocean variability in the U.S. Fishery Conservation Zone, 1976 /

"July 1979"

The history of Scotland, related in familiar conversations, by a father to his children: interspersed with moral and instructive remarks, and observations on the most leading and interesting subjects. Designed for the perusal of youth.

Summers, Gothic Bib., p. 63.

Stories by American authors.

v. 6. The village convict, by C. H. White. The Denver express, by A. A. Hayes. The misfortunes of Bro' Thomas Wheatley, by Lina R. Fairfax. The heartbreak cameo, by L. W. Champney. Miss Eunice's glove, by A. Webster. Brother Sebastian's friendship, by H. Frederic.--v. 7. The bishop's vagabond, by Octave Thanet. Lost, by E. Bellamy. Kirby's coals of fire, by Louise Stockton. Passages from the journal of a social wreck, by Margaret Floyd. Stella Grayland, by J. T. McKay. The image of San Donato, by Virginia W. Johnson.--v. 8. The brigade commander, by J. W. De Forest. Split zephyr, by H. A. Beers. Zerviah Hope, by Elizabeth S. Phelps. The life-magnet, by A. A. Adee. Osgood's predicament, by Elizabeth D. B. Stoddard.--v. 9. Marse Chan, by T. N. Page. Mr. Bixby's Christmas visitor, by C. S. Gage. Eli, by C. H. White. Young Strong of "The Clarion," by Milicent W. Shinn. How old Wiggins wore ship, by Captain R. T. Coffin. "--mas has come," by L. Kip.--v. 10. Pancha, by T. A. Janvier. The ablest man in the world, by E. P. Mitchell. Young Moll's peevy, by C. A. Stephens. Manmat'ha, by C. De Kay. A daring fiction, by H. H. Boyesen. The story of two lives, by Julia Schayer.

Magdalen: or, The penitant of Godstow. An historical novel.

Paged continuously: v. 1: 98 p.; v. 2: 4 p. . [101]-196 p.; v. 3: p. ., [199]-294 p.

An overview of the archaeological resources of the metropolitan St. Louis area /

A report submitted to the National Park Service by the Illinois State Museum Society in fulfillment of contract no. CX0001-4-0093.

Final report of 1979 archaeological investigations at the Interpretive Center Tract, Cahokia Mounds Historic Site /

"February 1980."

The River L'Abbe Mission : a French colonial church for the Cahokia Illini on Monks Mound /

Bibliography: p. [92]-99.

Instructive rambles in London and the adjacent villages. Designed to amuse the mind, and improve the understanding of youth ...

Mode of access: Internet.

Instructive rambles in London, and the adjacent villages. Designed to amuse the mind, and improve the understanding of youth.

Summers, Gothic Bib., p. 63.

Instructive rambles in London and the adjacent villages : designed to amuse the mind, and improve the understanding of youth /

Mode of access: Internet.

The cowslip, or, More cautionary stories in verse /

Publisher's ads, [2] p. at end, according to Moon.