Annotation

Description

Aes is the central regulator of the Escherichia coli maltose system. Aes catalyzes hydrolysis of p-nitrophenyl esters of fatty acids, preferring substrates with short (less than 8 in length) acyl chains. Aes binds to the maltose operon regulator, MalT, and inhibits MalT transcriptional activation activity in competition with its inducer, maltotriose. Aes also binds to alpha-galactosidase; this interaction stimulates Aes esterase activity and inhibits alpha-galactosidase, suggesting that Aes may have a physiological role in regulation of metabolism of carbohydrates. The enzyme is monomeric. The catalytic triad is predicted to comprise Ser165, Asp262, and His292. In the presented crystal structure of Acetyl Esterase from Salmonella typhimurium active site Ser-165 is phosphorylated.  

Functional assignment

Acetyl esterase 

Structure information

Unit cell parameters

Space Group

C 2 2 21  

Unit Cell

a=82.75Å, b=133.21Å, c=64.14Å
α=90.00, β=90.00, γ=90.00 

Solvent content

47.52  

Matthews coefficient

2.34  

Refinement

Data for the highest resolution shell is in parentheses.

Resolution range

30.00-1.55Å (1.59-1.55Å)  

R_all(%)

14.0 

R_work(%)

13.8 (16.2) 

R_free(%)

17.7 (20.5) 

Num. observed reflections

51613 (3733) 

Num. R_free reflections

2632 (201) 

Completeness(%)

99.6 (98.9) 

Model parameters

Num Atoms

2755  

Num Waters

472  

Num Hetatoms

640  

Model mean isotropic B factor

11.610Ų  

RMSD bond length

0.010Å  

RMSD bond angle

1.320°  

Filename uploaded

rcsb051617.pdb (uploaded on Mar 18, 2009 5:40 PM)  

Inserted

Mar 18, 2009