Primary structure of chicken liver dihydrofolate reductase

Biochemistry ◽  
1980 ◽  
Vol 19 (4) ◽  
pp. 667-678 ◽  
Author(s):  
A. Ashok Kumar ◽  
Dale T. Blankenship ◽  
Bernard T. Kaufman ◽  
James H. Freisheim
DNA Sequence ◽  
2004 ◽  
Vol 15 (4) ◽  
pp. 291-298
Author(s):  
Tadanori Aimi ◽  
Shoji Fukuhara ◽  
Maki Ishiguro ◽  
Yutaka Kitamoto ◽  
Tsutomu Morinaga

1996 ◽  
Vol 315 (1) ◽  
pp. 97-102 ◽  
Author(s):  
Ying-xin FAN ◽  
Ming JU ◽  
Jun-mei ZHOU ◽  
Chen-lu TSOU

It has been reported that the activation of dihydrofolate reductase (DHFR) from L1210 mouse leukaemia cells by KCl or thiol modifiers is accompanied by increased digestibility by proteinases [Duffy, Beckman, Peterson, Vitols and Huennekens (1987) J. Biol. Chem. 262, 7028–7033], suggesting a loosening up of the general compact structure of the enzyme. In the present study, the peptide fragments liberated from the chicken liver enzyme by digestion with trypsin in dilute solutions of urea or guanidine hydrochloride (GuHCl) have been separated by FPLC and sequenced. The sequences obtained are unique when compared with the known sequence of DHFR and thus allow the points of proteolytic cleavage identified for the urea- and GuHCl-activated enzyme to be at or near the active site. It was also indicated by the enhanced fluorescence of 2-p-toluidinylnaphthalene 6-sulphonate that conformational changes at the active site in dilute GuHCl parallel GuHCl activation. The above results indicate that the activation of DHFR in dilute denaturants is accompanied by a loosening up of its compact structure especially at or near the active site, suggesting that the flexibility at its active site is essential for the full expression of its catalytic activity.


FEBS Letters ◽  
1987 ◽  
Vol 212 (1) ◽  
pp. 98-102 ◽  
Author(s):  
Toshiyuki Takai ◽  
Kenji Wada ◽  
Tadashi Tanabe

1990 ◽  
Vol 194 (2) ◽  
pp. 598-602
Author(s):  
Mats ESTONIUS ◽  
Christina KARLSSON ◽  
Edward A. FOX ◽  
Jan-Olov HOOG ◽  
Barton HOLMQUIST ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document