title: Inhibition of oligo(glutamine) precipitation by glutamine-containing peptides.
abstract: When a solution of glutamine is added to solid 1,1'-carbonyldiimidazole, a mixture of oligo(glutamine)s up to about the 11-mer is formed rapidly. On standing overnight, the solution deposits a precipitate that does not easily redissolve. We have studied the inhibition of this precipitation by glutamine-containing peptides. We find that the alternating peptides (arg.gln)(4) and (arg.gln)(8) are efficient inhibitors of precipitation while arg(5), (glu.gln)(4), and a nonalternating octapeptide of the same composition as (arg.gln)(4) do not inhibit precipitation even though all the arg-containing peptides readily adsorb to oligo(glutamine) precipitates. A possible structural basis for this difference is discussed.
authors.affiliation: The Salk Institute for Biological Studies, San Diego, California 92186-5800, USA.
authors.forename: B C
authors.initials: BC
authors.lastname: Chu
authors.forename: L E
authors.initials: LE
authors.lastname: Orgel
mesh_terms: D000327:Adsorption; D011232:Chemical Precipitation; D005973:Glutamine / Q000737:chemistry*; D007093:Imidazoles; D066298:In Vitro Techniques; D009842:Oligopeptides / Q000138:chemical synthesis* / Q000737:chemistry / Q000302:isolation & purification*; D010455:Peptides / Q000138:chemical synthesis / Q000737:chemistry / Q000302:isolation & purification; D012996:Solutions; D013439:Sulfhydryl Reagents
chemical_list: D007093:Imidazoles; D009842:Oligopeptides; D010455:Peptides; D012996:Solutions; D013439:Sulfhydryl Reagents; D005973:Glutamine; C097188:polyglutamine; C006900:N,N-carbonyldiimidazole