Membrane protein

Evidence for and against the Davson- Danielli model of membrane structure The plasma membrane is thin and has double layers. The plasma membrane has two dark lines and a lighter central region. The two dark lines suggests the presence of the protein on either side. The lighter central region suggests the presence of phospholipids. The dark grainy appearance could be the ribosomes. Ribosomes appear as dark granules in the cytoplasm. Measured by rule: approximately 1 mm actual size 10 nm…

The process starts by binding of heat shock proteins to a large range of peptides under cellular stress conditions or during synthesis, after this reaction they can reach the extracellular space following to viral lysis or nacrosis, they also can carry antigenic peptides for cross-priming. Various…

receptors are a class of G-protein coupled receptors (GPCRs) which are activated by catecholamines in the central and peripheral nervous systems. Alpha-1 adrenergic receptors (1-AR) are systematic vasoconstrictors: their activation constricts blood vessels by the contraction of vascular smooth muscle. These transmembrane receptors are activated by the binding of epinephrine or norepinephrine, which creates intracellular signals via activation of the G-protein. The G-protein itself is a…

Protein synthesis is made up of two steps which are transcription and translation. The transcription part is when the information that is encoded in the DNA is taken away and it is the encoded in the mRNA and this information can then go to the cells that are within the nucleus and then onto in the cytoplasm. Then there is translation which is when the mRNA works with a ribosome and tRNA to be able to synthesize the proteins. Transcription The sequence of transcription starts with the Enzyme…

in mammals Fatty acid synthesis is catalyzed by entity domains of a very large polypeptide that includes an acyl carrier protein domain. Development of the mammalian Fatty Acid Synthase actually has involved gene fusion • Biosynthesis of fatty acid in plants: Plants can make enormous amount of fatty acids only some are common and major components. Long chain fatty acids are…

are protein molecules that receive chemical signals in the form of ligands and induce responses at cellular level. They are localized at the cell surface, cytoplasm or the nucleus, depending on their amino acid sequences. In addition to using these three different localizations to categorize receptors, the types of action of receptors are also used as a mean of classification. The four main classifications of receptors are: 1. Ionotropic (or ligand-gated ion channel) receptors, 2. G-protein…

appendage protein filaments that are assembled on the surfaces of many different microorganisms, such as bacteria and archea. The wide range of diverse microorganisms within the type IV pili family indicates that there must be both a common evolutionary origin, as well as a versatile functionality (Giltner, Nguyen and Burrows 2012). The formation of type IV pili occurs when the enzyme PilD, first recognized in the bacterial species Pseudomonas aeruginosa, catalyzes the breakdown of proteins into…

plasma membrane, identifying at least two component macromolecules and describing what their basic function is within the membrane. The eukaryotic plasma membrane is a phospholipids bilayer containing proteins and carbohydrates attached to the proteins and sterols. It is a fluid phospholipids bilayer embedded with proteins and glycoprotein. The phospholipids bilayer is arranged in such a manner that they form the center of the membrane. They also contain sterols, which makes the membrane less…

Gel electrophoresis is used to separate DNA, RNA, and protein molecules by using an electric field. Protein gel electrophoresis is similar to agarose gel electrophoresis, but runs protein bands instead. The technique of protein gel electrophoresis uses cross-linked polymers of acrylamide (which is a neurotoxin and requires careful handling) or polyacrylamide to separate proteins and small nucleic acids. This technique takes longer than the agarose gels used to separate larger nucleic acids. Also…

because it provides a stable, protective covering to protect the genome from any chemical or physical agents from harming it. In addition, the icosahedral shape is made up of identical subunits, the virus will better utilize its genome to encode proteins for the capsid. Finally, the last reason that I believe icosahedral structures have been favored by evolution is simply because they allow delivery of the genome by specific binding to external receptors on the host cell, which transmit specific…