Studies on the Complex Formations of L-Tryptophan or Adenosine with Mercury Compounds in the Artificial Intra and Extracellular Fluids

Abstract

Complex formation of L-tryptophan (Trp) or adenosine (Ado) with mercuric chloride (MC) or methylmercuric chloride (MMC) was examined in an artificial intracellular fluid (pH 8.0) and artificial extracellular fluid (pH 8.0). 1) A strong complex formation of L-tryptophan or adenosine with mercuric chloride was demonstrated in the artificial intracellular fluid containing oxianions (HPO2-4, HCO-3), while the complex formation in the artificial extracellular fluid was considerably weak, because of the high concentiation (110 mM) of chloride ion in this fluid. 2) Dissociation constants (K) of complexes of [MC·Trp], [MC·trptamine], [MC·indole], and [MC·Ado] were found to be 1.83×10-3M, 7.60×10-4M, 1.22×10-5M, and 2.30×10-2M, respectively, in phosphate buffer (32 mM, pH 8.0). 3) The complex formation of L-tryptophan or adenosine with methylmercuric chloride in the artificial intra or extra cellular fluid was much weaker than that with mercuric chloride.