PMID- 12694721
OWN - NLM
STAT- MEDLINE
DCOM- 20031216
LR  - 20190628
IS  - 0003-2697 (Print)
IS  - 0003-2697 (Linking)
VI  - 316
IP  - 1
DP  - 2003 May 1
TI  - A fluorimetric method for the determination of pepsin activity.
PG  - 11-4
AB  - An intramolecularly quenched fluorogenic peptide containing o-aminobenzoyl (Abz) 
      and ethylenediamine 2,4-dinitrophenyl (Eddnp) groups at amino- and 
      carboxyl-terminal amino acid residues, Abz-Lys-Pro-Ile-Glu-Phe-Phe-Arg-Leu-Eddnp, 
      was hydrolyzed by purified human pepsin, gastricsin, and gastric juice uniquely 
      at the Phe-Phe bond. Kinetic parameters determined for purified pepsin were 
      K(m)=0.68+/-0.11 microM; k(cat)=6.3+/-0.16s(-1); k(cat)/K(m)=9.26s(-1) 
      microM(-1); Gastricsin showed K(m)=2.69+/-0.18 microM; k(cat)=0.03+/-0.005s(-1); 
      k(cat)/K(m)=0.011s(-1) microM(-1). Gastric juice (21 samples) from subjects 
      without gastric disorders at endoscopy examination showed activities varying from 
      0.0008 to 9.72 micromolml(-1)min(-1). Pepstatin A inhibition of gastric juice 
      enzymatic activity was complete at 3.4x10(-5)M (final concentration) inhibitor. 
      In the proposed method the presence of a unique scissile bond in the synthetic 
      substrate provides a direct ratio between enzymatic activity and amount of 
      substrate hydrolyzed, and a unique step reaction facilitates the use of this 
      assay for the determination of the activity of aspartic proteinases in biological 
      fluids and during enzyme purification procedures.
FAU - da Silva Gomes, Roseli Aparecida
AU  - da Silva Gomes RA
AD  - Departamento de Ciencias Biologicas, Faculdade de Medicina do Triangulo Mineiro, 
      38015-050, Uberaba, Brazil. bioq@dcb.fmtm.br
FAU - Batista, Rodrigo Pedutti
AU  - Batista RP
FAU - Costa de Almeida, Andreia
AU  - Costa de Almeida A
FAU - da Fonseca, Daurin Narciso
AU  - da Fonseca DN
FAU - Juliano, Luis
AU  - Juliano L
FAU - Hial, Valdemar
AU  - Hial V
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - United States
TA  - Anal Biochem
JT  - Analytical biochemistry
JID - 0370535
RN  - 0 (Pepstatins)
RN  - EC 3.4.23.1 (Pepsin A)
RN  - EC 3.4.23.3 (gastricsin)
SB  - IM
MH  - Fluorometry/*methods
MH  - Gastric Juice/drug effects/enzymology
MH  - Humans
MH  - Kinetics
MH  - Pepsin A/*analysis
MH  - Pepstatins/pharmacology
MH  - Time Factors
EDAT- 2003/04/16 05:00
MHDA- 2003/12/17 05:00
CRDT- 2003/04/16 05:00
PHST- 2003/04/16 05:00 [pubmed]
PHST- 2003/12/17 05:00 [medline]
PHST- 2003/04/16 05:00 [entrez]
AID - S0003269703000253 [pii]
AID - 10.1016/s0003-2697(03)00025-3 [doi]
PST - ppublish
SO  - Anal Biochem. 2003 May 1;316(1):11-4. doi: 10.1016/s0003-2697(03)00025-3.