Comparative carbon-13, nitrogen-15, and phosphorus-31 nuclear magnetic resonance study on the flavodoxins from Clostridium MP, Megasphaera elsdenii, and Azotobacter vinelandii

Journal Article · Tue Nov 04 00:00:00 EST 1986 · Biochemistry; (United States)

DOI:https://doi.org/10.1021/bi00370a010· OSTI ID:6549183

Vervoort, J; Mueller, F; Mayhew, S G; van den Berg, W A.M.; Moonen, C T.W.; Bacher, A

The flavodoxins from Megasphaera elsdenii, Clostridium MP, and Azotobacter vinelandii were studied by /sup 13/C, /sup 15/N, and /sup 31/P NMR techniques by using various selectivity enriched oxidized riboflavin 5'-phosphate (FMN) derivatives. It is shown that the ..pi.. electron distribution in protein-bound flavin differs from that of free flavin and depends also on the apoflavoprotein used. In the oxidized state Clostridium MP and M. elsdenii flavodoxins are very similar with respect to specific hydrogen bond interaction between FMN and the apoprotein and the electronic structure of flavin. A vinelandii flavodoxin differs from these flavodoxins in both respects, but it also differs from Desulfovibrio vulgaris flavodoxin. The similarities between A. vinelandii and D. vulgaris flavodoxins are greater than the similarities with the other two flavodoxins. The differences in the ..pi.. electron distribution in the FMN of reduced flavodoxins from A. vinelandii and D. vulgaris are even greater, but the hydrogen bond patterns between the reduced flavins and the apoflavodoxins are very similar. In the reduced state all flavodoxins studied contain an ionized prosthetic group and the isoalloxazine ring is in a planar conformation. The results are compared with existing three-dimensional data and discussed with respect to the various possible mesomeric structures in protein-bound FMN. The results are discussed in light of the proposed hypothesis that specific hydrogen bonding to the protein-bound flavin determines the specific biological activity of a particular flavoprotein.

• Research Organization: Agricultural Univ., Wageningen, Netherlands
• OSTI ID: 6549183
• Journal Information: Biochemistry; (United States), Vol. 25:22
• Country of Publication: United States
• Language: English

Related Subjects

62 RADIOLOGY AND NUCLEAR MEDICINE
COENZYMES
NUCLEAR MAGNETIC RESONANCE
AZOTOBACTER
BACTERIA
CARBON 13
CLOSTRIDIUM
ISOALLOXAZINES
NITROGEN 15
PHOSPHORUS 31
PROTEINS
CARBON ISOTOPES
EVEN-ODD NUCLEI
HETEROCYCLIC COMPOUNDS
ISOTOPES
LIGHT NUCLEI
MAGNETIC RESONANCE
MICROORGANISMS
NITROGEN ISOTOPES
NUCLEI
ODD-EVEN NUCLEI
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
ORGANIC OXYGEN COMPOUNDS
PHOSPHORUS ISOTOPES
RESONANCE
STABLE ISOTOPES
550601* - Medicine- Unsealed Radionuclides in Diagnostics