Reaction of bovine and equine growth hormones with tetranitromethane.
Bovine and equine growth hormones were chemically modified with tetranitromethane, at pH 7.4 during 5 h and at pH 8.0 in the presence of 8 M urea during 1 h. a) Both hormones have very similar but not identical reactivities. b) The nitration of the reactive tyrosines and tryptophan residues at pH 7.4 produces no detectable changes in their immunological or somatotrophic activities. C) The nitration of all tyrosine residues in both hormones gives rise to a complete loss of somatographic activity with no alteration of the immunological activity.
D000596:Amino Acids / Q000032:analysis; D000804:Angiotensin II; D000818:Animals; D002417:Cattle; D002850:Chromatography, Gel; D013006:Growth Hormone / Q000302:isolation & purification; D006736:Horses; D006863:Hydrogen-Ion Concentration; D008697:Methane / Q000031:analogs & derivatives; D008970:Molecular Weight; D013045:Species Specificity; D013774:Tetranitromethane; D013997:Time Factors; D014364:Tryptophan / Q000276:immunology; D014443:Tyrosine / Q000276:immunology; D014508:Urea
D000596:Amino Acids; D000804:Angiotensin II; D014443:Tyrosine; D014364:Tryptophan; D014508:Urea; D013006:Growth Hormone; D013774:Tetranitromethane; D008697:Methane