Open AccessDistribution of the flavohaemoglobin, HMP, between periplasm and cytoplasm in Escherichia coli
Author(s) -
Vasudevan Subhash G.,
Tang Pan,
Dixon Nicholas E.,
Poole Robert K.
Publication year - 1995
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/j.1574-6968.1995.tb07361.x
Subject(s) - periplasmic space , lysozyme , cytoplasm , biology , escherichia coli , mutant , plasmid , microbiology and biotechnology , biochemistry , blot , osmotic shock , gene
The subcellular distribution of the soluble flavohaemoglobin (HMP) of Escherichia coli has been determined. Cells over‐expressing HMP from the cloned hmp gene on a multicopy plasmid were fractionated by osmotic shock and lysozyme treatment. Spectral analysis of subcellular fractions showed the CO‐binding haemoprotein to be cytoplasmic. However, Western blotting using antibody raised to purified HMP revealed approximately 30% of the protein to be periplasmic in the over‐expressing strain. Western analysis also revealed substantial levels of periplasmic HMP in a strain expressing only chromosomally encoded protein but none in an hmp mutant. The results are discussed in relation to protein function and the similar distribution reported for Vitreoscilla globin.