Research Article Immunology Free access Louis, Missouri,USA.
In Depth Tutorials and Information Oligomycin Molecular Biology The oligomycins are a family of macrolide antibiotics composed of three major members: This antibiotic has antifungal activity, but it is not clinically useful because of its toxicity to mice and HeLa Cells 1, 3.
However, Lardy et al 6 reported that oligomycins inhibit oxidative phosphorylation of mitochondria, a finding that attracted the attention of biochemists.
Since then the oligomycin family has been shown to be a specific and reversible inhibitor of two ATPases: In addition, it has been reported that oligomycins inhibit some drug-translocating ATPases that confer drug-resistance to mammalian and yeast cells, although the inhibition mechanism is unknown 7, 8and that oligomycins are suppressive agents for human B cell activation 4.
Because the three compounds are used extensively in the fields of biochemistry and molecular biology, their physicochemical properties are described.
Molecular Formulas and Formula Weights The molecular formulas and formula weights of oligomycins are and Structures Structures of the oligomycins are shown in Figure 1.
The three-dimensional structure of oligomycin B was determined by von Glehn et al 9. Structures of the oligomycins 2, 3, Molecular Absorption Coefficient e The maximal molecular absorbance coefficients of the oligomycins in methanol are 37, at nm for oligomycin A, 32, at nm for oligomycin B, and 33, at nm for oligomycin C 2.
Solubilities The oligomycins are stable compounds. They are almost insoluble in water but are soluble in water-miscible solvents such as ethanol, methanol, dimethyl sulfoxide, dimethylformamide 10 acetone, glacial acetic acid, and in ether 1.
Oligomycins are usually dissolved in ethanol and stored in a refrigerator.
The corresponding inhibitory concentrations IC50s toward HeLa cells are 0. Other Properties The melting points, infrared absorption spectra, and optical rotations of the oligomycins, including oligomycins D, E, G, and rutamycin B are available in the literatures5, Biochemical Properties Various ion proton -translocating ATPases are present in prokaryotic and eukaryotic organisms.
These ATPase are classified into three groups: In some cases, this ATPase is called the sodium pump. The inhibitory potency of oligomycin is often expressed as an amount of oligomycin per milligram of ATPase: The Fj portion is an oligomer composed of five different kinds of hydrophilic subunits named a, b, g, d, and e, and it includes the catalytic center for the synthesis or hydrolysis of ATP.
The F0 portion is an integral membrane protein composed of three bacteria or more eukaryotic organisms different kinds of hydrophobic subunits Table 1and it functions as a proton channel. The ATPase activity of the isolated F1 region is not inhibited by oligomycin However, OSCP does not contained a binding site for oligomycin; instead, it is one of the components required for correct binding between the F1 and F0 portions 18, Oligomycin-resistant mutants have been isolated from yeast and Chinese hamster ovary cell lines and analyzed genetically.
The majority of the mutations were mapped at loci oli 1 to oli 4 The oli 2 and oli 4 loci were found in the gene for subunit 6 of F0, whereas the oli 1 and oli 3 were found in the gene for subunit 9 of F0 Table 1 16, Some of the amino acids substituted in the mutants have been identified 23, OSCP apparently affects the oligomycin sensitivity indirectly.Reducing the Cytotoxicity of Lipid Nanoparticles Associated with a Fusogenic Cationic Lipid in a Natural Killer Cell Line by Introducing a Polycation-Based siRNA Core Molecular Pharmaceutics Nakamura, Yamada, Fujiwara, Sato, and Harashima.
Endometroid v Normal Serous v Normal ring finger protein 40 RNF40 _at chromosome 15 open reading frame 48 C15orf48 _at Zinc finger, CCHC domain containing An interaction is inferred when a bait protein is affinity captured from cell extracts by either polyclonal antibody or epitope tag and the associated interaction partner identified by Western blot with a specific polyclonal antibody or second epitope tag.
For detection of tyrosine‐phosphorylated proteins, proteins after 2D PAGE were blotted onto a polyvinylidene difluoride membrane (immobilom‐P, Millipore, Bedford, MA), and the membrane was stained with anti‐phosphotyrosine antibody (Amersham, Piscataway, NJ).
Lymphocyte-specific protein tyrosine kinase (Lck) is a SFK predominantly expressed in T-cells to regulate T-cell development and homeostasis [25, 26]. As a plasma membrane-associated protein, Lck is the key PTK that initiates intracellular signaling from T-cell receptor (TCR) on the surface [ 27, 28 ].
Natural killer cells form an immune synapse when targeted to a tumour cell. In this case, mitochondria from both natural killer cells and tumour cells polarize towards the immune synapse, indicating that the mobilization of mitochondria may have a role in both cell types, at the time of interaction.