Number Of Heme Proteins Research Articles

The Molecular Magic of “Meatless” Meats: Structural and Sequence Similarities between Soy Leghemoglobin and Bovine Globins

Plant‐based proteins are becoming more prevalent in the modern day due to humanity’s fight against climate change. How do scientists produce plant‐protein that tastes similar to animal‐protein? When comparing bovine hemoglobin (2qss), soy leghemoglobin (2GDM) and bovine myoglobin (2qss), the proteins differ by location, number of heme proteins, oxygen affinity and backbone alignment. Hemoglobin is found in red blood cells of animals. More specifically, myoglobin is found in the red blood cells of muscle tissue in animals. Leghemoglobin, however, is the byproduct of the symbiotic relationship between root nodules on legumes and nitrogen‐fixing bacteria that lives on them. However, all of these proteins are linked by the common molecule, heme. Plant‐based “meat” manufacturers suggest that this heme group, that is embedded in each of these globins, is responsible for this “meaty” taste. Additionally, the presence of umami‐inducing amino acids was investigated and glutamic acid surface prevalence related to flavor. Using the suite of structural analysis applications in the Protein Data Bank, such as FATCAT and fast2BLAST, the structural similarities between bovine hemoglobin, especially the heme itself, bovine myglobin and soy leghemoglobin can be illustrated, both quantitatively and qualitatively (e.g. 3D‐printed models).

When an amide is more like histidine than imidazole: the role of axial ligands in heme catalysis

Of the many subtle protein-cofactor interactions which facilitate oxidative catalysis by heme enzymes, the role of the axial ligand has for some time appeared to be fairly well understood. Recent studies from several laboratories, however, have provided good reason to reemphasize the importance of secondary interactions between the axial ligand and protein, as the results suggest that simple ligand identity is neither necessary nor sufficient for function. It has been widely proposed that the strong hydrogen bond between a proximal carboxylate and the histidine ligand of peroxidases assists O–O bond heterolysis and stabilizes the Fe(IV)=O center that is produced. Recent replacements of the axial ligand in a number of heme proteins have produced a few surprises, suggesting that the subtle interactions between the ligand and protein may in some cases be more important than the actual identity of the ligand.