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Mammalian Aeroallergens
Published in Harriet A. Burge, Bioaerosols, 2020
The domestic cat produces a number of different allergens, but the most abundant in terms of quantity of allergen produced is Fel d I (Felis domesticus I), formerly known as Cat 1. Fel d I is a 36-kDa acidic protein dimer that was first purified and characterized by Ohman et al. (1977). Immunochemical studies have shown that Fel d I is present in parotid tissue and may be transferred through saliva during grooming (Ohman et al., 1974). Bartholome et al. (1985) suggested that Feld I might originate from sebaceous glands, and Charpin et al. (1991) went on to show that antigen is produced in the Ultradermal hair follicles and accumulates in the hair roots before spreading to the tip of the hair shaft. It has also been shown that the antigen is produced by sebaceous glands and to a lesser extent by basal epithelial cells and that high concentrations are found on the fur and skin (Dabrowski et al., 1990). Morgenstern et al. (1991) suggested that the form of Fel d I produced by the salivary glands has a different molecular weight than that derived from the skin.
Unprecedented Technologies found in Nature Led by Harvesting the Geometry of Singularity
Published in Anirban Bandyopadhyay, Nanobrain, 2020
An essential component of a single microtubule is a tubulin protein dimer. Tubulin protein solution was dropped in the gap of a four-probe electrode array, then a DC bias was applied to order 15–20 molecules. For 8–100 tubulins, the resonance band remained independent of the number of molecules or the electrode geometry. Similar to the microtubule and neuron cell, a triplet of triplet resonance band was observed. The axon core, microtubule and tubulin have self-similar bands, with a common frequency region,—a similar structural symmetry governs the resonance in all the three systems. Helical distribution of neural branches, rings of proteins in the axonal core, spirals of proteins in the microtubule, α helices in the proteins, are the common structures, and the resonant energy transmission in generic spiral symmetry follows a quantized behavior (Sahu et al., US patent 9019685B2). Hence, a spiral symmetry possibly ensures coupling of all the clocks.
Toward Understanding the Intelligent Properties of Biological Macromolecules
Published in George K. Knopf, Amarjeet S. Bassi, Smart Biosensor Technology, 2018
One of the insights that has resulted from analysis of these high-resolution structure databases has been a general recognition of how proteins in sequence-specific DNA–protein complexes distort their DNA recognition sites. An example of this type of DNA distortion is shown in Figure 2.42 where an x-ray structure of the bacteriophage cro protein is presented on the right in the form of a ribbon diagram of its secondary structure. It is depicted binding to its 14-bp DNA recognition sequence (164). Note that at either end of the DNA region contacted by the protein dimer, the DNA helix axis bends to the right. Distortion of DNA binding sites by sequence-specific recognition proteins is a commonly observed phenomenon (165,166). It has led to the calculation of a DNA physical property parameter called the protein deformability (PD). The magnitude of any local PD region in a DNA binding site has been shown to be very much a local property that is dependent upon the dinucleotide neighbor pair sequence. That is, on average, sequence-specific proteins deform DNA not based upon which base j occurs at a specific position for the protein to interact with, but based upon the two dinucleotides ij and jk at that specific position j. The PD values for all 16 possible dinucleotide pairs in DNA have been determined. They are based upon averaged representations of how each protein specifically deformed its DNA recognition sequence in a dataset of nearly 100 high-resolution DNA–protein structures (167).
Molecular modeling strategy to design novel anticancer agents against UACC-62 and UACC-257 melanoma cell lines
Published in Egyptian Journal of Basic and Applied Sciences, 2023
Abdullahi Bello Umar, Adamu Uzairu
DMB3 docked in the binding site of V600E-BRAF (Figure 3) showed a good docking score (Table 1), indicating that it has bound into the binding site of one of the protomers in the protein dimer via the formation of two Hbond with LYS483 and CYS532. The O-atom of sulfonamide moiety formed one Hbond with LYS483 and the other one was formed between the OH group to CYS532 residue. Further, there was two π–π interaction (staked) from the active site and the molecule with TRP531 and PHE583 residues, which occur due to the intercalation of the `benzene ring (Figure 3). There is an additional alkyl interaction with (ALA481 and VAL471) and lastly π–alkyl interaction with four residues (LYS483, ILE463 and VAL471). The docking results in this study support our postulation that the active molecule might inhibit the growth of some melanoma cells via the inhibition of V600E-BRAF kinase, in a way similar to vemurafenib (Figure S3).
Global asymptotic stability in a model of networks
Published in Dynamical Systems, 2018
Hassan M. Fathallah-Shaykh, Abraham Freiji
We consider a new system of nonlinear ODEs, related to the Gause–Lotka–Volterra system and neural network equations, that models biological networks. The system is generic in the sense that it is applicable to mRNA, protein, protein dimer formation, or protein phosphorylation. The system may also be of interest to population biologists as it includes a saturation term. A key feature of this system is that it retains the interconnection matrix of the nonlinear influence of one species/molecule upon the growth of the other of the Gause–Lotka–Volterra equations (the interconnection matrix is defined in Subsection 2.2 ). This system was introduced in [14,36] and employed in [12–14] to model and study the dynamics of the Drosophila circadian clock. Goh proved that a nontrivial equilibrium of the Gause–Lotka–Volterra system is GAS if the interconnection matrix is Lyapunov-diagonally stability (LDS) [21].