Biomedical subjects

Anne Marie Jørgensen

Publications and source records attributed to Anne Marie Jørgensen.

2 recordsLinked to original sources

PubMed2005

Reduced and oxidized cytochrome c4 exhibit differences in dynamics.

The temperature-dependent dynamics of the fully reduced and fully oxidized forms of Pseudomonas stutzeri cytochrome c4 have been studied by Mössbauer spectroscopy. Prior to the dynamic analysis, an efficient labelling strategy has been developed for the expression of highly enriched (57)Fe recombinant cytochrome c4. Subsequently, the protein has been purified to apparent homogeneity. Mössbauer measurements were recorded in the temperature range 77-240 K for both protein forms. A detailed analysis of the high quality spectra is presented. Based on the information obtained from Mössbauer spectroscopy, similarities and differences between cytochrome c4, cytochrome c and HiPIP are discussed. The obtained results reveal that (a) cytochrome c4 exists in pure low spin electronic configuration in both oxidation states in the temperature range 77-240 K, (b) the heme pocket is more relaxed in cytochrome c4 than in cytochrome c, (c) the reduced cytochrome c4 is the most flexible at low temperatures, and (d) protein specific dynamics are most distinct in the oxidized protein.

Cytochrome c Group↗

PubMed2003

Cytoplasmic expression of the Achromobacter xylosoxidans blue copper nitrite reductase in Escherichia coli and characterisation of the recombinant protein.

The gene of the Achromobacter xylosoxidans (DSM 2402) blue copper-containing nitrite reductase was amplified using the polymerase chain reaction. DNA sequence analysis reveals that the amino acid sequence is identical to those of the GIFU1051 and the NCIMB11015 A. xylosoxidans nitrite reductases. The gene encoding the mature coding region for DSM 2402 nitrite reductase was cloned into a pET-vector, overexpressed in the cytoplasm of Escherichia coli BL21(DE3), and the expressed holoprotein was purified to apparent homogeneity by cation-exchange chromatography. The recombinant blue copper-containing nitrite reductase was obtained in high yields of 70mgL(-1) of culture. The specific catalytic activity as well as the electronic absorption and electron paramagnetic resonance spectra agree with corresponding data for the native protein. Mass spectroscopic analysis of the recombinant nitrite reductase gave a molecular weight of 36659.1Da for the apo-protein monomer, in agreement with the expected molecular mass based on the amino acid sequence.

Achromobacter denitrificans↗