Biomaterial Database

A continuous fluorometric assay for flavokinase. Properties of flavokinase from Peptostreptococcus elsdenii. 1977

S G Mayhew, and J H Wassink

A continuous fluorometric assay that utilizes apoflavodoxin as a trapping agent for riboflavin 5'-phosphate (FMN) has been developed for flavokinase (ATP:riboflavin 5'-phosphotransferase, EC 2.7.1.26). Use of this assay is illustrated in a procedure for the partial purification of flavokinase from the strict anaerobe Peptostreptococcus elsdenii. The purified enzyme catalyzed the formation of 8.3 nmol FMN - min-1 - mg-1 at 37 degrees C and had apparent Km values for riboflavin and ATP of 10 and 4.7 micronM, respectively. ATP could be replaced by ADP (22% of the rate observed with ATP) but not by GTP. The enzyme also phosphorylated 5-deaza- and 8-bromoriboflavin with activities of 15 and 70%, respectively, of that with riboflavin; it was inactive with iso riboflavin and deoxyriboflavin.

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D010462	Peptostreptococcus	A genus of gram-positive, anaerobic, coccoid bacteria that is part of the normal flora of humans. Its organisms are opportunistic pathogens causing bacteremias and soft tissue infections.
D010770	Phosphotransferases	A rather large group of enzymes comprising not only those transferring phosphate but also diphosphate, nucleotidyl residues, and others. These have also been subdivided according to the acceptor group. (From Enzyme Nomenclature, 1992) EC 2.7.	Kinases,Phosphotransferase,Phosphotransferases, ATP,Transphosphorylase,Transphosphorylases,Kinase,ATP Phosphotransferases
D012256	Riboflavin	Nutritional factor found in milk, eggs, malted barley, liver, kidney, heart, and leafy vegetables. The richest natural source is yeast. It occurs in the free form only in the retina of the eye, in whey, and in urine; its principal forms in tissues and cells are as FLAVIN MONONUCLEOTIDE and FLAVIN-ADENINE DINUCLEOTIDE.	Vitamin B 2,Vitamin G,Vitamin B2
D013050	Spectrometry, Fluorescence	Measurement of the intensity and quality of fluorescence.	Fluorescence Spectrophotometry,Fluorescence Spectroscopy,Spectrofluorometry,Fluorescence Spectrometry,Spectrophotometry, Fluorescence,Spectroscopy, Fluorescence
D017853	Phosphotransferases (Alcohol Group Acceptor)	A group of enzymes that transfers a phosphate group onto an alcohol group acceptor. EC 2.7.1.