Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
2006-9-12
pubmed:abstractText
Lumazine synthases have been observed in the form of pentamers, dimers of pentamers, icosahedral capsids consisting of 60 subunits and larger capsids with unknown molecular structure. Here we describe the analysis of the assembly of native and mutant forms of lumazine synthases from Bacillus subtilis and Aquifex aeolicus at various pH values and in the presence of different buffers using small angle X-ray scattering and electron microscopy. Both wild-type lumazine synthases are able to form capsids with a diameter of roughly 160 A and larger capsids with diameters of around 300 A. The relative abundance of smaller and larger capsids is strongly dependent on buffer and pH. Both forms can co-exist and are in some cases accompanied by other incomplete or deformed capsids. Several mutants of the B. subtilis lumazine synthase, in which residues in or close to the active site were replaced, as well as an insertion mutant of A. aeolicus lumazine synthase form partially or exclusively larger capsids with a diameter of about 300 A. The mutations also reduce or inhibit enzymatic activity, suggesting that the catalytic function of the enzyme is tightly correlated with its quaternary structure. The data show that multiple assembly forms are a general feature of lumazine synthases.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0022-2836
pubmed:author
pubmed:issnType
Print
pubmed:day
29
pubmed:volume
362
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
753-70
pubmed:meshHeading
pubmed:year
2006
pubmed:articleTitle
Multiple assembly states of lumazine synthase: a model relating catalytic function and molecular assembly.
pubmed:affiliation
Karolinska Institutet, Department of Biosciences, Center for Structural Biochemistry, S-14157 Huddinge, Sweden.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't