[The release of flavin adenine dinucleotide upon local conformational transition in electron-transferring flavoprotein induced by trimethylamine dehydrogenase]. / Vysvobozhdenie FAD pri lokal'nom konformatsionnom perekhode, indutsiruemom trimetilaminodegidrogenazoi v elektrontransportnom flavoproteine.
Bioorg Khim
; 30(3): 247-53, 2004.
Article
en Ru
| MEDLINE
| ID: mdl-15344654
The electron-transferring proteins, trimethylamine dehydrogenase (TMAD) and electron-transferring flavoprotein (ETF) from the bacterium Methylophilius methylotrophus, were studied in vitro by fluorescence spectroscopy. Flavin adenine dinucleotide (FAD) was found to be capable of a slow and spontaneous release from ETF, which is accompanied by an increase in flavin fluorescence. At a rather high ionic strength (0.1 M NaCl or 50 mM phosphate), the FAD release is sharply activated by TMAD preparations that induce a local conformational transition in ETF. The values of tryptophan fluorescence polarization and lifetime and the use of the Levshin-Perrin equation helped show that the size of protein particles remain unchanged upon the TMAD and ETF mixing; i.e., these proteins themselves do not form a stable complex with each other. The protein mixture did not release flavin from ETF in the presence of trimethylamine and formaldehyde. In this case, a stable complex between the proteins appeared to be formed under the action of formaldehyde. Upon a short-term incubation of ETF with ferricyanide, FAD was hydrolyzed to flavin mononucleotide (FMN) and AMP. This fact explains the previous detection of AMP in ETF preparations by some researches. A fluorescence method was proposed for distinguishing FAD from FMN in solution using ethylene glycol. The English version of the paper: Russian Journal of Bioorganic Chemistry, 2004, vol. 30, no. 3; see also http://www.maik.ru.
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Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Oxidorreductasas N-Desmetilantes
/
Methylophilus methylotrophus
/
Flavoproteínas Transportadoras de Electrones
/
Flavina-Adenina Dinucleótido
Idioma:
Ru
Revista:
Bioorg Khim
Año:
2004
Tipo del documento:
Article
Pais de publicación:
Rusia