Copper(II) Ion and Nickel(II) Ion Complexes with 2-Amino-2-(hydroxymethyl)-1,3-propanediol. Reactions with Sodium Hydroxide

Quantification of single-stranded nucleic acid and oligonucleotide interactions with metal ions by affinity capillary electrophoresis: part I

“…We initially considered Tris as a buffer as it is commonly used as a medium for studies of metal ion-DNA interactions with DNA [11,12,21] and is particularly suitable for capillary electrophoresis experiments owing to its low conductivity [22]. However, transition metal ions form complexes of reasonable stability with Tris [20,[23][24][25][26][27][28][29] and ternary M(DNA)(Tris) complexes with oligonucleotides or DNA [16,20]. Measured macroscopic K B values in the presence of a large excess of buffer will relate to mixtures of species.…”

Free-Metal Ion Depletion by "Good's" Buffers

“…Both are composed of two noncovalently linked polypeptides, a heavy chain (a) of about 34,000 daltons and a light chain (1) of about 28,000 daltons (molecular size). In the past 2 years, advances in protein microsequencing and recombinant DNA technologies have led to a definition of the primary structure of various human and murine class II molecules (4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14). Both a and 1 polypeptides may be divided into two external domains of approxi-…”

“….0 (t), 62.0 (t), 48.9 (d), 45.0 (d), 39.5 (t), 34.9 (t), 28.7 (s), 26.5 (t), 25.9 (q), 21.8 (d), 3x 21.0 (q), 19.7 (t), 17.7 (q), 16.6 (q (5) (where KB is the equilibrium constant of the buffer), it is obvious that Kf = K'fKB (6) Furthermore, the metal ion interaction of various "Good's" buffers can be quite complex, and Eq. 6 represents only the most simple case, that is, no hydroxo complex formation (Eq.…”

Structures of purine nucleosidase fromTrypanosoma bruceibound to isozyme-specific trypanocidals and a novel metalorganic inhibitor

“…We then measured the K ii of Cu 2+ ions at different pH values, revealing that tight binding occurs at basic pH, which is apparently a consequence of the deprotonation of one or more amino-acid residues endowed with near-neutral pK a . Since Tris buffer is capable of forming coordination complexes in solution with transition-metal ions (Allen et al, 1967;Hall et al, 1962;Fischer et al, 1979), we investigated whether the observed inhibition of IAGNH could be modulated by this organic compound. Tris itself is a poor competitive inhibitor of IAGNH at neutral pH, with a K i value of 41 mM; however, this decreases to 14.2 mM at pH 8.2 and to 1.2 mM at pH 8.5.…”