Leghemoglobin structure

Mauro, V.P., Nguyen, T., Katinakis, P. Verma, D.P.S. (1985). Primary structure of the soybean nodulin-23 gene and potential regulatory elements in the 5 -flanking regions of nodulin and leghemoglobin genes. Nucleic Acids Research 13, 239-49. 

Metz, B.A., Welters, P., Hoffman, H.J., Jensen, E.O., Schell, J. de Bruijn, F.J. (1988). Primary structure and promoter analysis of leghemoglobin gene of the stem nodulated tropical legume Sesbania rostrata conserved coding sequences, cis elements and trans-acting factors. Molecular and General Genetics 214, 181-91. 

Figure 6.14 Conservation of three-dimensional structure. The tertiary structures of human hemoglobin (a chain), human myoglobin, and lupine leghemoglobin are conserved. Each herne group contains an iron atom to which oxygen binds. [Drawn from lHBB.pdb, IMBD.pdb, and IGDJ.pdb.]...

Anyone aware of the similar biochemical functions of hemoglobin, myoglobin, and leghemoglobin could expect the structural similarities. In a growing number of other cases, however, a comparison of three-dimensional structures has revealed striking similarities between proteins that were not expected to be related. A case in point is the protein actin, a major component of the cytoskeleton (Section 34.2), and heat shock protein 70 (Hsp-70), which assists protein folding inside cells. These two proteins were found to be noticeably similar in structure despite only 1.5.6% sequence identity (Figure 6.15). On the basis of their three-dimensional structures,... 

A research study of the structure of ferric leghemoglobin is to be undertaken. Your job is to provide a sample of each leghemoglobin for this research, and it is to be done by isoelectric focusing of a soybean extract. 

El I folk, Ada Chem. Scand. 17, S343 (1963). Resolved into four components on DEAE-cellulose column ElFfolk, ibid. 14, 609 (1960). Suggested to act as an oxido-reduction catalyst in the symbiotic nitrogen fixation idem, ibid. 15, 975 (1961). Primary structure of soybean leghemoglobin Ell-folk, Sievers, ibid. 25, 3532 (1971). 

The primary and even tertiary structure of M. and hemoglobins from many different species show striking similarities. M. appears to be phylogenetically the oldest known heme protein, from which hemoglobin evolved as an independent molecule 600 million years ago. M. also appears to be phylogenetically related to Leghemoglobin (see). 

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