electronic supplementary material for activation …10.1007/s00775-012-0945...electronic...

Post on 27-Mar-2018

223 Views

Category:

Documents

1 Downloads

Preview:

Click to see full reader

TRANSCRIPT

Electronic Supplementary Material

For

Activation Mechanism of MelB Tyrosinase from Aspergillus oryzae

by Acidic Treatment

Nobutaka Fujieda・Michiaki Murata・Shintaro Yabuta・Takuya Ikeda・Chizu Shimokawa・Yukihiro Nakamura・Yoji Hata・Shinobu Itoh

N. Fujieda・M. Murata・S. Yabuta・T. Ikeda・C. Shimokawa・S. Itoh

Department of Material and Life Science,

Division of Advanced Science and Biotechnology,

Graduate School of Engineering,

Osaka University,

2-1 Yamada-oka,

Suita, Osaka 565-0871, Japan

e-mail: S.I.: shinobu@mls.eng.osaka-u.ac.jp, N.F.: fujieda@mls.eng.osaka-u.ac.jp

Yukihiro Nakamura・Yoji Hata

Research Institute Gekkeikan Sake Co., Ltd,

101 Shimotoba-koyanagi-cho,

Fushimi-ku, Kyoto, 612-8385, Japan

2

Contents

Figure S1 Time courses of the absorption change at 475 nm for the reaction of tyrosinase with

L-DOPA and with L-tyrosine Figure S2 Michaelis-Menten plot Figure S3 The gelfiltration chromatography of the pro-tyrosinase and activated tyrosinase Figure S4 HPLC elution diagram of the final reaction mixture of trypsin treated tyrosinase and

4-methylphenol Figure S5 Plot of Vobs vs. [S] for the oxygenation of p-substituted phenol by acid-treated

tyrosinase Figure S6 Plot of Vobs vs. [S] for the oxygenation of p-substituted phenol by trypsin-treated

tyrosinase Scheme S1 Proposed catalytic mechanism of phenolase and catecholase activity of tyrosinase Scheme S2 Dopachrome Formation Pathway from Tyrosine Scheme S3 Simplified catalytic system of phenolase reaction of melB tyrosinase Scheme S4 Electrophilic aromatic substitution mechanism for the oxygen atom transfer process

from a (µ-η2:η2-peroxo)dicopper(II) species to a phenol substrate

3

Figure S1 Fig. S1 Time courses of the absorption change at 475 nm for the reaction of tyrosinase (0.155 µM) with (a) L-tyrosine (0.1 mM) and with (b) L-DOPA (0.2 mM) in 10 mM Tris-HCl buffer (pH 7.2) at 25 ºC under aerobic conditions. The pro-tyrosinase (open circle) and acid-treated tyrosinase (square)

4

Figure S2 Fig. S2 Michaelis-Menten plot; Vobs vs. the concentration of L-tyrosine in 0.1 M citrate buffer at pH

6.0. [tyrosinase]= 0.059 µM

5

Figure S3 Fig. S3 (a) The gel filtration chromatography of the intact wild type tyrosinase (solid line) at pH 7.0 and acid-treated tyrosinase (dotted line) at pH 3.0. (b) Determination of molecular weight of the acid-treated tyrosinase in glycine-HCl buffer at pH 3.0. Thyroglobulin (669 kDa), apo-ferritin (443 kDa), dimeric alcohol dehydrogenase (150 kDa), monomeric alcohol dehydrogenase (75 kDa), and dimeric carbonic anhydrase (58 kDa) were used as marker proteins for determination of molecular weight (open circle). Closed circle indicated the results of the acid-treated tyrosinase (112 kDa). The calculated molecular weights are shown in the brackets.

6

Figure S4 Fig. S4 HPLC elution diagram of the final reaction mixture of trypsin treated tyrosinase (0.155 mM) and 4-methylphenol (0.33 mM) in the presence of NH2OH (8.0 mM).

0 5 10 15 20 25

OH

Me

OH

Me

OH

O

Me

O

Buffer

7

Figure S5 Fig. S5 Plot of vobs vs [S] for the oxygenation of (a) p-F-phenol, (b) p-Cl-phenol, (c) p-COOMe-phenol by acid-treated tyrosinase. Inset; Hanes-woolf plot for the same reaction.

8

Figure S6 Fig. S6 Plot of vobs vs [S] for the oxygenation of (a) p-Me-phenol, (b) p-F-phenol, (c) p-Cl-phenol, (d) p-COOMe-phenol by trypsin-treated tyrosinase. Inset; Hanes-woolf plot for the same reaction.

9

Scheme S1 Scheme S1: Proposed Catalytic Cycle of Phenolase and Catechlase Activity of Tyrosinase.

10

Scheme S2 Scheme S2: Dopachrome Formation Pathway from Tyrosine.

OH

HOOC NH2

OH

HOOC NH2

O

HOOC NH2

OH O

OHOH

NHHOOC

OO

NHHOOC

Tyrosine DOPA DOPAquinone

DOPAchrome (475 nm)

Tyrosinase Tyrosinase

11

Scheme S3 Scheme S3: Simplified Catalytic System of Phenolase Reaction of melB Tyrosinase.

CuIICuII

His

His

HisHis

His

His

OH

CuIICuII

His

His

HisHis

His

His

O

CuICuI

His

His

HisHis

His

HisO2

O

R

OH

OH

R

OH

Deoxy form

Oxy form Met form

NH2OH

Borate

R

O

O

R

O

O

B

12

Scheme S4 Scheme S4: Electrophilic Aromatic Substitution Mechanism for the Oxygen Atom Transfer Process from a (µ-η2:η2-Peroxo)dicopper(II) Species to a Phenol Substrate.

CuII CuII

His

His

HisHis

His

His

O

O

R

OH

R

-O

CuII CuII

His

His

HisHis

His

His

O

O

H+

rds k

R

O

CuII CuII

His

His

HisHis

His

His

O

O

H

K

CuII CuII

His

His

HisHis

His

His

OH

OO

R

top related