Thermodynamics and kinetics of the cooperative binding of bacteriophage T4-coded gene 32 (helix destabilizing) protein to nucleic acid lattices

Journal Article · Wed Oct 01 00:00:00 EDT 1980 · Biophys. J.; (United States)

DOI:https://doi.org/10.1016/S0006-3495(80)84964-2· OSTI ID:6795994

Kowalczykowski, S C; Lonberg, N; Newport, J W; Paul, L S; von Hippel, P H

In this paper we summarize a series of thermodynamic, and preliminary kinetic, studies on the molecular details and specificity of interaction of phage T4-coded gene 32-protein (GP32) with nucleic acid lattices. It is shown that the binding of GP32 to short (l = 2 to 8 residues) oligonucleotides is essentially independent of base composition and sugar-type, as well as of salt concentration. In contrast, cooperative (continuous) or isolated binding of GP32 to single-stranded polynucleotides is base and sugar composition-dependent and highly dependent on salt concentrations. Binding constants (K), cooperativity parameters (..omega..), and binding site sizes (n) are determined for binding to various nucleic acid lattices under a variety of environmental conditions. These results are used to show that GP32 can bind to nucleic acid lattices in two different conformations, and to characterize the molecular details of these binding species. Preliminary experiments have also been carried out on the kinetics of GP32 association to, and dissociation from, single-stranded nucleic acid lattices. In particular, fluorescence stopped-flow measurements of the dissociation of GP32 from such lattices as a function of lattice saturation (and protein cluster size) can be interpreted to suggest that the protein may translocate on the lattice before dissociation. These studies permit an approach to possible rates and mechanisms of such translocation events.

• Research Organization: Univ. of Oregon, Eugene, OR (United States)
• OSTI ID: 6795994
• Journal Information: Biophys. J.; (United States), Vol. 32:1
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
CRYSTAL LATTICES
ULTRASTRUCTURAL CHANGES
DNA
BIOCHEMICAL REACTION KINETICS
RNA
BACTERIOPHAGES
COMPLEXES
DISSOCIATION
HELICAL INSTABILITY
MOLECULAR BIOLOGY
MOLECULAR STRUCTURE
STRUCTURAL CHEMICAL ANALYSIS
THERMODYNAMICS
CRYSTAL STRUCTURE
INSTABILITY
KINETICS
MICROORGANISMS
MORPHOLOGICAL CHANGES
NUCLEIC ACIDS
ORGANIC COMPOUNDS
PARASITES
PLASMA INSTABILITY
PLASMA MACROINSTABILITIES
REACTION KINETICS
VIRUSES
550200* - Biochemistry
550700 - Microbiology