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Biophysical Characteristics of Tus, the Replication Arrest Protein of Escherichia coli.     
Yazarlar (4)
Prof. Dr. Fatma Filiz ARI Prof. Dr. Fatma Filiz ARI
Kırşehir Ahi Evran Üniversitesi, Türkiye
Aikaterina Skokotas
Gregory Moe
Thomas Hill
Devamını Göster
Özet
Tus, a DNA-binding protein, mediates arrest of DNA replication in Escherichia coli. Tus binds to DNA sequences called Ter sites, located in the terminus region of the chromosome, and forms replication-arrest complexes that block movement of DNA replication forks in a polar fashion. We have analyzed Tus to determine some of its physical parameters and biochemical characteristics. Native Tus had an s(20,w) of 3.2, a Stokes' radius of 23 Å, an axial ratio of 2, and a molar absorption coefficient of 39,700 M-1 cm-1. The data also indicated that Tus existed as a monomeric protein in solution and when complexed with its cognate DNA binding site. Secondary structure estimated from the circular dichroism spectrum suggested that Tus consisted of 40% α-helix, 0% β-sheet, 15% turn, and 45% aperiodic structure. The isoelectric point of native Tus (pH 7.5) was significantly different than that calculated from its amino acid sequence (pH 10.1), possibly because the tertiary structure of Tus perturbs the ionization of several residues. In addition, partial proteolytic digests of free Tus protein did not produce a subfragment of Tus that retained DNA binding activity, but did demonstrate that Tus was resistant to proteolysis when complexed with a Ter site.
Anahtar Kelimeler
Makale Türü Özgün Makale
Makale Alt Türü SSCI, AHCI, SCI, SCI-Exp dergilerinde yayımlanan tam makale
Dergi Adı JOURNAL OF BIOLOGICAL CHEMISTRY
Dergi ISSN 0021-9258
Dergi Tarandığı Indeksler SCI
Makale Dili İngilizce
Basım Tarihi 02-1994
Cilt No 269
Sayı 6
Sayfalar 4027 / 4034
Doi Numarası 10.1016/s0021-9258(17)41737-6
BM Sürdürülebilir Kalkınma Amaçları
Atıf Sayıları
SCOPUS 20
Biophysical Characteristics of Tus, the Replication Arrest Protein of Escherichia coli.

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