Hybrid restriction enzymes: zinc finger fusions to Fok I cleavage domain.

A long-term goal in the field of restriction-modification enzymes has been to generate restriction endonucleases with novel sequence specificities by mutating or engineering existing enzymes. This will avoid the increasingly arduous task of extensive screening of bacteria and other microorganisms for new enzymes. Here, we report the deliberate creation of novel site-specific endonucleases by linking two different zinc finger proteins to the cleavage domain of Fok I endonuclease. Both fusion proteins are active and under optimal conditions cleave DNA in a sequence-specific manner. Thus, the modular structure of Fok I endonuclease and the zinc finger motifs makes it possible to create "artificial" nucleases that will cut DNA near a predetermined site. This opens the way to generate many new enzymes with tailor-made sequence specificities desirable for various applications.

Crystal structure of the membrane-exposed domain from a respiratory quinol oxidase complex with an engineered dinuclear copper center.

Cytochrome oxidase is a membrane protein complex that catalyzes reduction of molecular oxygen to water and utilizes the free energy of this reaction to generate a transmembrane proton gradient during respiration. The electron entry site in subunit II is a mixed-valence dinuclear copper center in enzymes that oxidize cytochrome c. This center has been lost during the evolution of the quinoloxidizing branch of cytochrome oxidases but can be restored by engineering. Herein we describe the crystal structures of the periplasmic fragment from the wild-type subunit II (CyoA) of Escherichia coli quinol oxidase at 2.5-A resolution and of the mutant with the engineered dinuclear copper center (purple CyoA) at 2.3-A resolution. CyoA is folded as an 11-stranded mostly antiparallel beta-sandwich followed by three alpha-helices. The dinuclear copper center is located at the loops between strands beta 5-beta 6 and beta 9-beta 10. The two coppers are at a 2.5-A distance and symmetrically coordinated to the main ligands that are two bridging cysteines and two terminal histidines. The residues that are distinct in cytochrome c and quinol oxidases are around the dinuclear copper center. Structural comparison suggests a common ancestry for subunit II of cytochrome oxidase and blue copper-binding proteins.

Noise-tolerance feasibility for restricted-domain Information Retrieval systems

Information Retrieval systems normally have to work with rather heterogeneous sources, such as Web sites or documents from Optical Character Recognition tools. The correct conversion of these sources into flat text files is not a trivial task since noise may easily be introduced as a result of spelling or typeset errors. Interestingly, this is not a great drawback when the size of the corpus is sufficiently large, since redundancy helps to overcome noise problems. However, noise becomes a serious problem in restricted-domain Information Retrieval specially when the corpus is small and has little or no redundancy. This paper devises an approach which adds noise-tolerance to Information Retrieval systems. A set of experiments carried out in the agricultural domain proves the effectiveness of the approach presented.

Cross Florida Barge Canal restudy report D,Dsum,F; Engineering Dapp1; Engineering, appendix A DappA; Economics : environmental impact statement.

F also available in microfiche.

West Engineering Annex

View from the northeast. Old carpenter's shop is on the right next to the Annex which was built to replace it. On verso: Engineering shops

West Engineering Annex

Profs. J.B. Davis & Mortimer Cooley, architects? Engineering Shops from 1885-1923. Later used as West Engineering Annex 1923. Architecture Dept. in east wing 1923-1927; Survey Dept. in east wing 1927; Auto Lab in west wing; part of Auto Lab destroyed by fire 1937; rest demolished 1956.

West Engineering Annex

Addition comprised of a central section with tower and a one story wing on the west. Engineering shops. Several people in image.

West Engineering Annex

Profs. J.B. Davis & Mortimer Cooley, architects? Engineering Shops from 1885-1923. Later used as West Engineering Annex 1923. Architecture Dept. in east wing 1923-1927; Survey Dept. in east wing 1927; Auto Lab in west wing; part of Auto Lab destroyed by fire 1937; rest demolished 1956. On verso: Engineering Laboratory. Female person in image.

Engineering Laboratory - U of M

Photograph of drawing by Benno Rohnert. On verso: "Center- First Engineering Bldg. Brick & frame 1881-82. Right-Abandoned campus carpenter shop moved against west side 1883 and used for wood shop. Left-First unit of 3 story brick building started 1885" Original two buildings removed in 1888.

An annotated bibliography of patents related to coastal engineering /

"November 1979."

Description of Risk Reduction Engineering Laboratory test and evaluation facilities.

Mode of access: Internet.

Careers in engineering.

Mode of access: Internet.

Engineering control of occupational safety and health hazards : recommendations for improving engineering practice, education and research : summary report of the Engineering Control Technology Workshop Technical Panel.

Mode of access: Internet.

Stratigraphy of the unsaturated zone and uppermost part of the Snake River Plain aquifer at Test Area North, Idaho National Engineering Laboratory, Idaho /

Mode of access: Internet.

Science and engineering personnel : a national overview /

"NSF 80-316."