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Arsenals of Pharmacotherapeutically Active Proteins and Peptides: Old Wine in a New Bottle
Published in Debarshi Kar Mahapatra, Swati Gokul Talele, Tatiana G. Volova, A. K. Haghi, Biologically Active Natural Products, 2020
The myoglobin is a heme protein of muscles which stores oxygen. It is the first protein to have its three-dimensional structure elucidated by John Kendrew and his colleagues. It is polypeptide of 154 amino acids. The molecule of myoglobin consists of eight α helices, each of which is designated by a letter from A-H. These helices envelop the heme group (contains a porphyrin ring and an iron ion) located between His64 and His93. The iron ion in the myoglobin molecule is bound to six ligands: four nitrogen atoms of pyrroles, imidazole side chain of His93 and the sixth position is occupied by the oxygen molecule. In the deoxymyoglobin, the His93 stabilizes the heme group and shifts iron away from the heme group out of the plane.
Allometric Relationships
Published in Arthur T. Johnson, Biology for Engineers, 2019
The mass of hemoglobin has already been given by Equation 7.4.24. Myoglobin is the oxygen-binding molecule in the muscles. It has one heme group rather than the four in hemoglobin. Oxygen is transferred from red blood cell hemoglobin to solution in the blood to muscle myoglobin. The mass of myoglobin in the body of mammals is (Adolph, 1949) () mmy=3.32×10−4m1.31
A review of thermodynamic concepts
Published in Ronald L. Fournier, Basic Transport Phenomena in Biomedical Engineering, 2017
The use of Equation 2.202 is illustrated in the following example for the binding of oxygen to myoglobin. Myoglobin is an oxygen-binding protein found in muscles that store oxygen molecules and release the oxygen when the oxygen partial pressure becomes low, e.g., during strenuous exercise. Myoglobin has only one site available for the binding of oxygen. The absorption spectra of myoglobin bound to oxygen is different than that for free myoglobin and this can be used to determine, at a given partial pressure of oxygen, the fraction of myoglobin that is bound to oxygen.
Acute exercise-induced irisin release in healthy adults: Associations with training status and exercise mode
Published in European Journal of Sport Science, 2018
Shanhu Qiu, Edit Bosnyák, Gunnar Treff, Jürgen Michael Steinacker, Andreas Michael Nieß, Karsten Krüger, Frank Christoph Mooren, Martina Zügel, Uwe Schumann
Therefore, the primary aims of this study were to determine in healthy adults: (1) whether irisin response to acute exercise differs between subjects with different fitness levels; and (2) whether irisin response to acute exercise varies between running and cycling modes. Moreover, it is recognized that muscle damage, as reflected by changes in biomarkers such as creatine kinase (CK), aspartate aminotransferase (AST), and myoglobin (Mb), can be observed in response to acute exercise (Singh, Guelfi, Landers, Dawson, & Bishop, 2011). Based on this and in light of the cross-sectional reports that irisin is negatively correlated with CK in patients with thyroid disorders (Ruchala, Zybek, & Szczepanek-Parulska, 2014; Zybek-Kocik et al., 2018), the secondary aim of this study was to assess whether irisin release in response to acute exercise is associated with any changes in biomarkers of muscle damage assessed by CK, AST, and Mb profiles.
Electron paramagnetic resonance of globin proteins – a successful match between spectroscopic development and protein research
Published in Molecular Physics, 2018
Sabine Van Doorslaer, Bert Cuypers
Globins are globular haem-containing proteins that consist of a small number of α-helices. A bioinformatics survey of putative globins revealed that these proteins occur as three families (the myoglobin-like (M), the sensor (S) and the truncated globin (T) family) in two structural classes [1,3,4]. Within each family, the globin can be a single-domain (SD) or a chimeric protein [1]. Mammalian myoglobin has the so-called classical globin fold, consisting of eight α-helices that are organised in a canonical 3-over-3 (i.e. 3/3) sandwich (Figure 1(a)). The α-helices are labelled with letters A to H from the N- to the C-terminus. The haem group is positioned in the hydrophobic centre and is a protoporphyrin ring with a central iron atom. This haem iron is bound to the His at position 8 of the F helix (F8His), which is conserved in all globins. This side of the haem is referred to as the proximal side of the haem. In mammalian Mb, the opposite (distal) side of the haem allows binding of exogenous gasses, such as O2 (Figure 2(a)). In other proteins, such as neuroglobin (Ngb) [5], an endogenous amino acid (for Ngb: E7His) is binding to the haem iron (Figure 2(b)). This is often referred to as a ‘hexacoordinate’ globin, where the term hexacoordination is referring to the bis-histidine ligation of the haem iron [6]. It is unclear at present which of the two coordination forms came first [6].