title: 3-azido-L-tyrosine as a photoinhibitor of tubulin:tyrosine ligase. Role of thiol groups.
abstract: We have synthesized the photoactivatable probes 3-azido-L-tyrosine and p-azido-L-phenylalanine and studied their capacity to inhibit the incorporation of [3H]tyrosine into tubulin catalyzed by tubulin:tyrosine ligase. Without illumination, only 3-azido-L-tyrosine reversibly inhibits the enzyme. Upon illumination, both reagents irreversibly photoinactivate the enzyme in a similar way. The ligase can be protected against photoinactivation by reversibly blocking essential thiol groups with pCMB during illumination.
authors.affiliation: Interdisciplinary Research Center, KU Leuven, Kortrijk, Belgium.
authors.forename: K
authors.initials: K
authors.lastname: Coudijzer
authors.forename: M
authors.initials: M
authors.lastname: Joniau
mesh_terms: D000345:Affinity Labels; D000818:Animals; D001386:Azides / Q000494:pharmacology*; D001921:Brain / Q000201:enzymology; D002729:Chloromercuribenzoates / Q000494:pharmacology; D066298:In Vitro Techniques; D010453:Peptide Synthases / Q000037:antagonists & inhibitors*; D010649:Phenylalanine / Q000031:analogs & derivatives; D010777:Photochemistry; D013329:Structure-Activity Relationship; D013438:Sulfhydryl Compounds; D013552:Swine; D014404:Tubulin / Q000378:metabolism; D014443:Tyrosine / Q000031:analogs & derivatives* / Q000494:pharmacology; D020245:p-Chloromercuribenzoic Acid
chemical_list: D000345:Affinity Labels; D001386:Azides; D002729:Chloromercuribenzoates; D013438:Sulfhydryl Compounds; D014404:Tubulin; C065394:3-azidotyrosine; D014443:Tyrosine; D010649:Phenylalanine; D020245:p-Chloromercuribenzoic Acid; D010453:Peptide Synthases; C023213:tyrosyltubulin ligase