In the present study the analytical potential of HPLC-MS/MS was utilized for the structural characterization of a post-translational modification of statherin. Human salivary statherin (M-av 5380.0 +/- 0.3 Da) is transformed by the action of transglutaminase 2 into a cyclic derivative with an average molecular mass of 5363.0 +/- 0.3 Da. The intra-molecular bridge is generated by the loss of an ammonia molecule between the unique lone-pair donating nucleophile Lys-6 and one acceptor among the seven glutamine residues of statherin. Digestion of the cyclic derivative with chymotrypsin, proteinase K, and carboxypeptidase Y, monitored by HPLC - electrospray ionization-ion trap-mass spectrometric analysis, demonstrated that cyclization involved almost specifically Gln-37 (> 95%), with the percentage of Gln-39 implicated in the cross-linking being less than 5%. The main derivative was named cyclo-statherin Q-37. Guinea pig transglutaminase 2 showed high affinity for statherin in vitro (K-m = 0.65 +/- 0.06 mu M). Cyclo-statherin was detected in vivo by HPLC-electros pray ionization ion trap-mass spectrometry analysis of whole human saliva and it accounted for about 1% of total statherin. Detection of cyclo-statherin in whole saliva is suggestive of a putative role of this molecule in the formation of the "oral protein pellicle".

Cabras, T., Inzitari, R., Fanali, C., Scarano, E., Patamia, M., Sanna, M. T., Pisano, E., Giardina, B., Castagnola, M., Messana, I., HPLC-MS characterization of cyclo-statherin Q37, a specific cyclization product of human salivary statherin generated by transglutaminase 2, <<JOURNAL OF SEPARATION SCIENCE>>, 2006; (29): 2600-2606 [http://hdl.handle.net/10807/25623]

HPLC-MS characterization of cyclo-statherin Q37, a specific cyclization product of human salivary statherin generated by transglutaminase 2

Cabras;Tiziana; Inzitari;Rosanna; Fanali;Chiara; Scarano;Emanuele; Patamia;Maria; Sanna;Maria Teresa; Pisano;Elisabetta; Giardina;Bruno; Castagnola;Massimo; Messana
2006

Abstract

In the present study the analytical potential of HPLC-MS/MS was utilized for the structural characterization of a post-translational modification of statherin. Human salivary statherin (M-av 5380.0 +/- 0.3 Da) is transformed by the action of transglutaminase 2 into a cyclic derivative with an average molecular mass of 5363.0 +/- 0.3 Da. The intra-molecular bridge is generated by the loss of an ammonia molecule between the unique lone-pair donating nucleophile Lys-6 and one acceptor among the seven glutamine residues of statherin. Digestion of the cyclic derivative with chymotrypsin, proteinase K, and carboxypeptidase Y, monitored by HPLC - electrospray ionization-ion trap-mass spectrometric analysis, demonstrated that cyclization involved almost specifically Gln-37 (> 95%), with the percentage of Gln-39 implicated in the cross-linking being less than 5%. The main derivative was named cyclo-statherin Q-37. Guinea pig transglutaminase 2 showed high affinity for statherin in vitro (K-m = 0.65 +/- 0.06 mu M). Cyclo-statherin was detected in vivo by HPLC-electros pray ionization ion trap-mass spectrometry analysis of whole human saliva and it accounted for about 1% of total statherin. Detection of cyclo-statherin in whole saliva is suggestive of a putative role of this molecule in the formation of the "oral protein pellicle".
Inglese
Cabras, T., Inzitari, R., Fanali, C., Scarano, E., Patamia, M., Sanna, M. T., Pisano, E., Giardina, B., Castagnola, M., Messana, I., HPLC-MS characterization of cyclo-statherin Q37, a specific cyclization product of human salivary statherin generated by transglutaminase 2, <<JOURNAL OF SEPARATION SCIENCE>>, 2006; (29): 2600-2606 [http://hdl.handle.net/10807/25623]
File in questo prodotto:
Non ci sono file associati a questo prodotto.

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/10807/25623
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus ND
  • ???jsp.display-item.citation.isi??? ND
social impact