Mass spectroscopy Complex lipids

The crystal structure of bovine cytochrome c oxidase (Complex IV) homodimer has been determined to a resolution of 1.8 A (Shinzawa-Itoh et al., 2007). This integral membrane protein complex composed of thirteen different subunits per monomer is responsible for the reduction of molecular oxygen to water during aerobic respiration, with concomitant proton pumping across the mitochondrial inner membrane. A combination of high resolution X-ray structure analysis of the integral lipids in bovine Complex IV with mass spectroscopy analysis of their chain lengths and the positions of the unsaturated bonds of the... 

Parkes and co-workers have also conducted H NMR studies on s5movial fluid from patients with rheumatoid arthritis. Tbe nature of the nontransferrin-bound iron in the synovial fluid of patients with inflammatory joint disease was investigated. Transferrin is an iron ion transport protein. In these patients the synovial fluid contains non-transferrin-bound iron which appears to be in low-molecular-mass, redox-active complexes of unknown type. This form of iron has the adverse effect of stimulating free-radical lipid peroxidations involving oxygen. 500 MHz spin-echo H NMR spectroscopy was used to show that the incubation of patient synovial fluid with the powerful Fe(III)... 

Infrared spectroscopy has proved to be a valuable tool for characterizing and differentiating microbial cells [4, 6, 45-48]. Given the complex nature of such micro-organisms, the spectra can contain a superposition of hundreds of infrared modes. However, the FTIR spectra of bacteria show bands predominantly due to the protein component [6]. Although the cells also contain DNA and RNA structures, carbohydrates and lipids, the various cell and membrane proteins form the major part of the cell mass. Figure 7.15 shows parts of the infrared spectra of Escherichia coli and a typical protein, i.e. ribonuclease A, illustrating their similarity. Bands due to carbohydrates and lipids may also be observed in bacterial infrared spectra to a lesser extent. 

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