Fixation protein

Figure 16.5 Immunostained peptide arrays after various treatments of fixation, protein cross-linking, and antigen retrieval, as indicated at the top. Each row has a different peptide that is immunoreactive for the antibody denoted to the left. Column A represents the baseline condition, without any treatment whatsoever. Column B shows immunoreactivity of each peptide after overnight formalin fixation. Column C shows the immunoreactivity after first coating the array with an irrelevant protein (casein) followed by overnight formalin fixation. Column D illustrates the immunoreactivity of the peptides after the treatment of column C, and then antigen retrieval. Reproduced with permission from Reference 15, 2006 American Society for Clinical Pathology.

Copper is an essential element. Copper plays a significant role in several physiological processes - photosynthesis, respiration, carbohydrate distribution, nitrogen reduction and fixation, protein metabolism, and cell wall metabolism. Many plant metalloenzymes contain copper. It also influences water permeability of xylem vessels and thus controls water relationships. It is mainly complexed with organic compounds of low molecular weight and with proteins (Henze and Umland, 1987). Kabata-Pendias and Pendias (1984) have compiled data on the Cu concentrations in... 

To increase disease resistance, resistance to pests, shelf life, level of nitrogen fixation (protein content), and resistance to temperature extremes. 

Many key protein ET processes have become accessible to theoretical analysis recently because of high-resolution x-ray stmctural data. These proteins include the bacterial photosynthetic reaction centre [18], nitrogenase (responsible for nitrogen fixation), and cytochrome c oxidase (the tenninal ET protein in mammals) [19, 20]. Although much is understood about ET in these molecular machines, considerable debate persists about details of the molecular transfonnations. 

In addition, Ee protein-1 has at least two noncatalytic roles related to nitrogen fixation, and presumably Ee protein-2 and Ee protein-3 do also. The first function is somehow involved in the early stages of EeMo-cofactor biosynthesis because mutant strains having a deletion in nifil produce neither Ee protein nor EeMo-cofactor, rather only a EeMo-cofactor-deficient apo-MoEe protein (104,105). The second role involves insertion of preformed EeMo-cofactor into these apo-MoEe proteins (106). 

Nicolas, M.-T., Morse, D., Bassot, J. M., and Hastings, J. W. (1991). Colocalization of luciferin-binding protein and luciferase to the scintillons of Gonyaulax polyedra revealed by double immunolabeling after fast-freeze fixation. Protoplasma 160 159-166. 

The elucidation of the crystal structures of two high-spin EPR proteins has shown that the proposals for novel Fe-S clusters are not without substance. Two, rather than one novel Fe-S cluster, were shown to be present in nitrogenase, the key enzyme in the biotic fixation of molecular nitrogen 4, 5). Thus the FeMoco-cofactor comprises two metal clusters of composition [4Fe-3S] and [lMo-3Fe-3S] bridged by three inorganic sulfur atoms, and this is some 14 A distant from the P-cluster, which is essentially two [4Fe-4S] cubane moieties sharing a corner. The elucidation of the crystal structure of the Fepr protein (6) provides the second example of a high-spin EPR protein that contains yet another unprecedented Fe-S cluster. 

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