Linked Life Data

10417406

Source:http://linkedlifedata.com/resource/pubmed/id/10417406

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
Pt 8
pubmed:dateCreated
1999-9-23
pubmed:databankReference
pubmed:abstractText
The growth mechanisms and physical properties of the orthorhombic crystal form of beef liver catalase were investigated using in situ atomic force microscopy (AFM). It was observed that the crystals grow in the <001> direction by an unusual progression of sequential two-dimensional nuclei of half unit-cell layers corresponding to the 'bottoms' and 'tops' of unit cells. These were easily discriminated by their alternating asymmetric shapes and their strong growth-rate anisotropy. This pattern has not previously been observed with other macromolecular crystals. Orthorhombic beef liver catalase crystals exhibit an extremely high defect density and incorporate great numbers of misoriented microcrystals, revealed intact by etching experiments, which may explain their marginal diffraction properties. To facilitate interpretation of AFM results in terms of intermolecular interactions, the structure of the orthorhombic crystals, having an entire tetramer of the enzyme as the asymmetric unit, was solved by molecular replacement using a model derived from a trigonal crystal form. It was subsequently refined by conventional techniques. Although the packing of molecules in the two unit cells was substantially different, with very few exceptions no significant differences in the molecular structures were observed. In addition, no statistically significant deviation from ideal 222 molecular symmetry appeared within the tetramer. The packing of molecules in the crystal revealed by X-ray analysis explained in a satisfying way the process of crystal growth revealed by AFM.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0907-4449
pubmed:author
pubmed:issnType
Print
pubmed:volume
55
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1383-94
pubmed:dateRevised
2007-7-24
pubmed:meshHeading
pubmed:year
1999
pubmed:articleTitle
Structure of orthorhombic crystals of beef liver catalase.
pubmed:affiliation
Institute of Molecular Biology, Academia Sinica, Taipei 11529, Taiwan.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, Non-P.H.S., Research Support, Non-U.S. Gov't