title: Interactions of archaeal chromatin proteins Alba1 and Alba2 with nucleic acids.
abstract: BACKGROUND
  Architectural proteins have important roles in compacting and organising chromosomal DNA. There are two potential histone counterpart peptide sequences (Alba1 and Alba2) in the Aeropyrum pernix genome (APE1832.1 and APE1823).
  
  
  RESULTS
  THESE TWO PEPTIDES WERE EXPRESSED AND THEIR INTERACTIONS WITH VARIOUS DNAS WERE STUDIED USING A COMBINATION OF VARIOUS EXPERIMENTAL TECHNIQUES: surface plasmon resonance, UV spectrophotometry, circular dichroism-spectropolarimetry, gel-shift assays, and isothermal titration calorimetry.
  
  
  CONCLUSIONS
  Our data indicate that there are significant differences in the properties of the Alba1 and Alba2 proteins. Both of these Alba proteins can thermally stabilise DNA polynucleotides, as seen from UV melting curves. Alba2 and equimolar mixtures of Alba1/Alba2 have greater effects on the thermal stability of poly(dA-dT).poly(dA-dT). Surface plasmon resonance sensorgrams for binding of Alba1, Alba2, and equimolar mixtures of Alba1/Alba2 to DNA oligonucleotides show different binding patterns. Circular dichroism indicates that Alba2 has a less-ordered secondary structure than Alba1. The secondary structures of the Alba proteins are not significantly influenced by DNA binding, even at high temperatures. Based on these data, we conclude that Alba1, Alba2, and equimolar mixtures of Alba1/Alba2 show different properties in their binding to various DNAs.
authors.affiliation: Biotechnical Faculty, University of Ljubljana, Ljubljana, Slovenia.
authors.forename: Miha
authors.initials: M
authors.lastname: Črnigoj
authors.forename: Zdravko
authors.initials: Z
authors.lastname: Podlesek
authors.forename: Mateja
authors.initials: M
authors.lastname: Zorko
authors.forename: Roman
authors.initials: R
authors.lastname: Jerala
authors.forename: Gregor
authors.initials: G
authors.lastname: Anderluh
authors.forename: Nataša Poklar
authors.initials: NP
authors.lastname: Ulrih
mesh_terms: D041522:Aeropyrum / Q000235:genetics; D000595:Amino Acid Sequence; D019843:Archaeal Proteins / Q000737:chemistry / Q000378:metabolism*; D001483:Base Sequence; D002843:Chromatin / Q000378:metabolism*; D004247:DNA / Q000737:chemistry / Q000378:metabolism*; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009691:Nucleic Acid Denaturation; D010446:Peptide Fragments / Q000378:metabolism; D011485:Protein Binding; D017433:Protein Structure, Secondary; D044366:Transition Temperature
chemical_list: D019843:Archaeal Proteins; D002843:Chromatin; D010446:Peptide Fragments; D004247:DNA