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H E Parge

Publications and source records attributed to H E Parge.

22 records · Page 2Linked to original sources
PubMed1985

X-ray studies on triclinic crystals of fatty acid binding protein. Examples of an extremely X-ray-resistant protein.

Fatty acid binding protein (pI 7.0) from bovine liver cytosol was crystallized using polyethylene glycol 4000 and 6000 as precipitating agents. The crystals are triclinic, space group P1. One molecule of 14 kDa occupies the unit cell with constants a = 33.5 A, b = 39.4 A, c = 30.6 A, alpha = 113.6 degrees, beta = 113.8 degrees, gamma = 88.8 degrees. Crystal diffraction extends to at least 2.25 A resolution and the crystals are stable in the X-ray beam for more than 450 h. One native data set to 2.5 A resolution has been collected.

Animals↗
PubMed1984

Crystallization of and preliminary X-ray diffraction data for TET-repressor and the TET-repressor-tetracycline complex.

The TET-repressor encoded by the transposon Tn10 has been crystallized along with the repressor-tetracycline complex. Both crystals belong to the space group P43212 (or P41212) with cell dimensions a = b = 74.3(1) A, c = 94.2(2) A and a = b = 73.3(1) A, c = 94.6(2) A for the free and complexed repressor, respectively. There is one molecule of molecular weight 23,000 per asymmetric unit, and the biologically active dimer therefore consists of two identically formed subunits which are related by a crystallographic 2-fold axis. This isomorphism of TET-repressor and its tetracycline complex suggests that only minor, subtle changes in structure trigger binding to or release of the operator. The crystals of the native protein permit X-ray data collection to 3.2 A and those of the complexed repressor to 2.8 A.

Crystallization↗
PubMedDate not supplied

Understanding the structure and antigenicity of gonococcal pili.

Pili--filamentous protein structures found on the cell surface of many infectious gram-negative bacteria--often are virulence factors that mediate adherence to host epithelial cells. The pilus, a major surface antigen of the gonococcus, is formed by the specific association of thousands of repeating identical protein subunits (pilin). Structural studies of the pilin protein and the pilus fiber may aid the rational design of a peptide-based vaccine by providing information on the antigenic surface of pili that includes the identification of sequence-distant antigenic regions that are localized to single areas of the three-dimensional structure. Preliminary results suggest that the pilin subunit has structural similarity to the 4-alpha-helix bundle fold in proteins such as the coat protein subunit of tobacco mosaic virus and myohemerythrin. Therefore, the monomeric protein myohemeythrin was used to identify structural correlations for antigenic determinants on 4-alpha-helix bundle proteins such as pilin.

Antigens, Bacterial↗