1. Development of peptide chip for rough diagnosis Deguchi Nao E-mail address : ac1210nd@apps.kct.ac.jp Department of Material Sciences & Chemical Engineering, Kitakyushu National College of Technology

2. introduction ・ Severe illness that are difficult to cure cause significant impact on our daily lives. ・ However, with early detection, it is quite possible to slow the progression, or even cure the disease with appropriate treatment. As a method to easily diagnose these diseases, I have been developing a peptide chip that could potentially be a break-thorough for simple diagnostic methodologies. As a method to easily diagnose these diseases, I have been developing a peptide chip that could potentially be a break-thorough for simple diagnostic methodologies.

3. It is understood that the majority of the causes of untreatable diseases originate in some kinds of abnormality in the intracellular signal transduction system. If there are methodologies to which we can monitor these intercellular signal transductions, diagnosis of these untreatable diseases will be possible. it is practically impossible to completely understand the intracellular signal transductions. however Protein phosphorylation signaling which is one of the most important and versatile intracellular signaling methods

4. － a reaction of the  -phosphate group of ATP transferring to a hydroxy group at the side chain of serine, threonine and tyrosine residues, which are included in substrate peptides or proteins in cells. protein phosphorylation 200 kinds of protein kinase, which is an enzyme catalyzing phosphorylation reaction, in human body. In order to monitor all protein kinase activities at once, I have tried to develop a analytical technique utilizing peptide array and MALDI-TOF-MS.

5. principle of MALDI-TOF-MS + - P P substrate peptide substrate photocleavage compound P P detector mass of phosphorylated peptide is increased by 80 rate of phosphorylation of MS spectra

6. purpose In order to conduct mass spectrometry using a peptide array, Our team needs substrate peptides with the photo-cleavable part by ionization laser synthesis 2-bromo-2-(2-nitrophenyl)acetic acid (BNPA)

7. method ●BNPA 2-(2-nitrophenyl)acetic acid (5.0 g) + thionyl chloride (8 ml) In carbon tetrachloride (5 ml) N-bromosuccinimide (6.0 g) + CCl 4 (25 ml) + catalytic amount of benzoyl peroxide 65 ℃ 1.5 ｈ ice(25 g) extract 3 x 25 ml CH 2 Cl 2 recrystallization from CH 2 Cl 2 75 ℃ 4.5 ｈ 1.0 ｈ

8. + + result Figure. 1 H-NMR mass of observed fragment ion proposed structure 242 244 214 216 Table. mass spectrometry ・ shape: Solid needle ・ color: Clear ・ mp: 59.6 ~ 63.0 ℃

9. substrate Immobilized concept conclusion I've tried the synthesis of the photo-cleavable compound. The synthesized one was identified with BNPA by 1 H-NMR and mass spectrometry.