NMR structural studies on a nonnatural deoxyribonucleoside which mediates recognition of GC base pairs in pyrimidine.cntdot.purine.cntdot.pyrimidine DNA triplexes

Biochemistry ◽  
1993 ◽  
Vol 32 (41) ◽  
pp. 11228-11234 ◽  
Author(s):  
Ishwar Radhakrishnan ◽  
Dinshaw J. Patel ◽  
E. Scott Priestley ◽  
Huw M. Nash ◽  
Peter B. Dervan
Keyword(s):  
Structural Studies ◽  
Base Pairs ◽  
Dna Triplexes

NMR structural studies of intramolecular (Y+)n.cntdot.(R+)n(Y-)n DNA triplexes in solution: imino and amino proton and nitrogen markers of G.cntdot.AT base triple formation

Biochemistry ◽  
1991 ◽  
Vol 30 (37) ◽  
pp. 9022-9030 ◽  
Author(s):  
Ishwar Radhakrishnan ◽  
Xiaolian Gao ◽  
Carlos De los Santos ◽  
David Live ◽  
Dinshaw J. Patel
Keyword(s):  
Structural Studies ◽  
Dna Triplexes

Structural studies of the Msx-1 homeodomain–DNA complex I

1999 ◽  
Vol 55 (12) ◽  
pp. 2039-2040
Author(s):  
Stacy DeWees ◽  
James H. Geiger
Keyword(s):  
Dna Binding ◽  
Structural Studies ◽  
Hanging Drop ◽  
Unit Cell Parameters ◽  
Orthorhombic Space Group ◽  
Base Pairs ◽  
Cell Parameters ◽  
Dna Binding Specificity ◽  
Peg 4000 ◽  
Dna Complex

Crystals of the Msx-1 homeodomain–DNA complex have been obtained by hanging-drop vapor diffusion at 293 K in 12% PEG 4000 and 0.1 M sodium acetate pH 4.6. The homeodomain consists of 60 amino acids and is the DNA-binding domain. The DNA in the complex was 16 base pairs with the sequence 5′-TGTCACTAATTGAAGG-3′, containing an overhang T at each end. The crystals diffract to 2.15 Å (99.8% completeness) using cryogenic (123 K) conditions. The crystals belong to the orthorhombic space group P212121, with unit-cell parameters a = 33.66, b = 60.96, c = 83.37 Å. The structure will illuminate the details of Msx-1–DNA binding specificity and clarify its role in transcriptional regulation. Mutations in Msx-1 cause craniofacial deformities in mice.

Structural studies of DNA gyrase

1984 ◽  
Vol 42 ◽  
pp. 164-167
Author(s):  
T. Kirchhausen ◽  
J. Wang ◽  
S. C. Harrison
Keyword(s):  
Microscopic Study ◽  
Dna Gyrase ◽  
Staphylococcal Nuclease ◽  
Dependent Manner ◽  
Type Ii ◽  
Structural Studies ◽  
Electron Microscopic ◽  
Base Pairs ◽  
Gyrase A ◽  
Negative Supercoils

DNA gyrase, a prokaryotic type II topoisomerase, can introduce negative supercoils into DNA in an ATP-dependent manner and relax negative supercoils in the absence of ATP. Gyrase is a tetramer of two A subunits (MW 105,000) and two B subunits (MW 95,000), and it interacts with about 140 base pairs of DNA (based on staphylococcal nuclease and DNase I protection experiments). We have undertaken an electron microscopic study of gyrase and its binding to DNA, in order to determine how DNA wraps in its complex with the protein.

Ribosome Structural Organization

1974 ◽  
Vol 32 ◽  
pp. 332-333
Author(s):  
James A. Lake
Keyword(s):  
Ribosomal Proteins ◽  
Structural Organization ◽  
Three Dimensional ◽  
Small Subunit ◽  
Structural Studies ◽  
X Ray Diffraction ◽  
Specific Antibodies ◽  
X Ray ◽  
E Coli ◽  
Complete Sequences

The understanding of ribosome structure has advanced considerably in the last several years. Biochemists have characterized the constituent proteins and rRNA's of ribosomes. Complete sequences have been determined for some ribosomal proteins and specific antibodies have been prepared against all E. coli small subunit proteins. In addition, a number of naturally occuring systems of three dimensional ribosome crystals which are suitable for structural studies have been observed in eukaryotes. Although the crystals are, in general, too small for X-ray diffraction, their size is ideal for electron microscopy.

Structural Studies on Mitotic Spindle Fibres

1978 ◽  
Vol 36 (3) ◽  
pp. 615-626
Author(s):  
J.R. Mcintosh
Keyword(s):  
Chemical Composition ◽  
Mitotic Spindle ◽  
Structural Studies ◽  
Mitotic Apparatus ◽  
Chemical Studies ◽  
Medical Interest ◽  
Spindle Fibres

The mitotic apparatus is a structure of obvious biological and medical interest, but it has proved to be a difficult cellular machine to understand. The chemical composition of the spindle is only slightly elucidated, largely because of the difficulties in preparing useful isolates of the structure. Chemical studies of the mitotic spindle have been reviewed elsewhere (Mcintosh, 1977), and will not be discussed further here. One would think that structural studies on the mitotic apparatus (MA) in situ would be straightforward, but even with this approach there is some disagreement in the results obtained with various methods and by different investigators. In this paper I will review briefly the approaches which have been used in structural studies of the MA, pointing out the strengths and problems of each approach. I will summarize the principal findings of the different methods, and identify what seem to be fruitful avenues for further work.

Image registration with a computer driven S.T.E.M.

1978 ◽  
Vol 36 (1) ◽  
pp. 98-99
Author(s):  
A.M.H. Schepman ◽  
J.A.P. van der Voort ◽  
J.E. Mellema
Keyword(s):  
Spot Size ◽  
Scanning Transmission Electron Microscope ◽  
Small Computer ◽  
Structural Studies ◽  
Area Of Interest ◽  
Transmission Electron ◽  
Scanning Transmission ◽  
Specimen Area ◽  
On Line ◽  
Minimum Distances

A Scanning Transmission Electron Microscope (STEM) was coupled to a small computer. The system (see Fig. 1) has been built using a Philips EM400, equipped with a scanning attachment and a DEC PDP11/34 computer with 34K memory. The gun (Fig. 2) consists of a continuously renewed tip of radius 0.2 to 0.4 μm of a tungsten wire heated just below its melting point by a focussed laser beam (1). On-line operation procedures were developped aiming at the reduction of the amount of radiation of the specimen area of interest, while selecting the various imaging parameters and upon registration of the information content. Whereas the theoretical limiting spot size is 0.75 nm (2), routine resolution checks showed minimum distances in the order 1.2 to 1.5 nm between corresponding intensity maxima in successive scans. This value is sufficient for structural studies of regular biological material to test the performance of STEM over high resolution CTEM.

Sign in / Sign up

Export Citation Format

Share Document