+ Site Statistics
+ Search Articles
+ Subscribe to Site Feeds
EurekaMag Most Shared ContentMost Shared
EurekaMag PDF Full Text ContentPDF Full Text
+ PDF Full Text
Request PDF Full TextRequest PDF Full Text
+ Follow Us
Follow on FacebookFollow on Facebook
Follow on TwitterFollow on Twitter
Follow on LinkedInFollow on LinkedIn

+ Translate

The oxygenated flavohaemoglobin from Escherichia coli: evidence from photodissociation and rapid-scan studies for two kinetic and spectral forms

The oxygenated flavohaemoglobin from Escherichia coli: evidence from photodissociation and rapid-scan studies for two kinetic and spectral forms

Biochemical and Biophysical Research Communications 187(1): 94-100

The kinetics of dissociation and reassociation of the oxygenated species of Escherichia coli flavohaemoglobin (Hmp) were studied using stopped-flow rapid-scan and flash photolysis spectrophotometry at 25 degrees C. The oxygenated compound(s) form rapidly on mixing oxygen with the NADH-reduced flavohaemoglobin. On exhaustion of NADH, with residual oxygen, decay occurs in two phases to give a form in which haem b and flavin are oxidized. Spectral changes during this process suggest a direct release of O2- from the oxy form. Photodissociation of the oxygenated species generates the unliganded protein, which recombines with oxygen to give two spectrally and kinetically distinct forms. The reversibility of the oxygen reaction and the rapid reassociation kinetics after photodissociation confirm the haemoglobin-like features of this protein.

(PDF same-day service: $19.90)

Accession: 041708197

Download citation: RISBibTeXText

PMID: 1325799

DOI: 10.1016/s0006-291x(05)81463-9

Related references

Photodissociation of oxygenated cytochrome o viteoscilla and kinetic studies of reassociation. Journal of Biological Chemistry 261(8): 3544-3547, 1986

The formation and decay of the oxyferrous forms of the cytochromes p 450 isolated from rhizobium japonicum rapid spectral scan and stopped flow studies. Biochimica et Biophysica Acta 828(2): 144-150, 1985

The reaction of cytochrome o in escherichia coli with oxygen low temperature kinetic and spectral studies. Biochemical Journal 184(2): 379-390, 1979

The reaction of cytochrome omicron in Escherichia coli with oxygen. Low-temperature kinetic and spectral studies. Biochemical Journal 184(2): 379-389, 1979

Rapid kinetic studies of the catalytic mechanism of thymidylate synthase from escherichia coli. FASEB Journal 4(7): A2301, 1990

Methylenetetrahydrofolate reductase from Escherichia coli: elucidation of the kinetic mechanism by steady-state and rapid-reaction studies. Biochemistry (American Chemical Society) 40(21): 05-15, 2001

Reactions of the Escherichia coli flavohaemoglobin (Hmp) with oxygen and reduced nicotinamide adenine dinucleotide: evidence for oxygen switching of flavin oxidoreduction and a mechanism for oxygen sensing. Proceedings. Biological Sciences 255(1344): 251-258, 1994

Rapid quench kinetic studies of the mutants at the high affinity metal site of escherichia coli glutamine synthetase. Abstracts of Papers American Chemical Society 198: MBTD 97, 1989

NO sensing by FNR: regulation of the Escherichia coli NO-detoxifying flavohaemoglobin, Hmp. Embo Journal 21(13): 3235-3244, 2002

Distribution of the flavohaemoglobin, HMP, between periplasm and cytoplasm in Escherichia coli. Fems Microbiology Letters. 125(2-3): 219-224, 1995

Haem, flavin and oxygen interactions in Hmp, a flavohaemoglobin from Escherichia coli. Biochemical Society Transactions 22(3): 709-713, 1994

Spectral and kinetic evidence for the existence of two forms of bathorhodopsin. Proceedings of the National Academy of Sciences of the United States of America 84(11): 3699-3703, 1987