Biochemistry chapter 3 Flashcards
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Collagen, elastin, Kerstin, actin, and tubulin. Structural proteins generally have a highly repetitive secondary structure and a supersecondary structure- —–a repetitive organization of secondary structure elements together sometimes referred as motif. This regulatory gives many structural proteins a fibrous nature.
What are the primary structural proteins in the body? What is a motif ?
<p>A characteristic trihelical fiber( three alpha Helics woven together toform a secondary helix) and makes up most of the extracellular matrix of connective tissue. {{1 1 0.png}}</p>
<p>What is Collagen ?</p>
Another component of the extracellular matrix of connective tissue. Its primarily role is to stretch and then recoil like a spring., which restores the original shape of the tissue
What is elastic ?
A protein that makes up microfilament and the thin filaments in myofibrils. It is the most abundant protein in eukaryotic cells.
What are Actins ?
<p>Intermediate filament proteins found in epithelial cells. It contributes to the mechanical integrity of the cell and also function as regulatory proteins. Its the primary protein that makes up hair and nails. {{4 1 0.png}}</p>
<p>What are Keratins ?</p>
The protein that makes up microtubules, Microtubules are important in providing structure, chromosome separation in mitosis, and intracellular transport with kinesin and dynein( you will know what they are in other cards)
What is Tubulin ?
They display enzymatic activity, using ATPases that power the conformational change necessary for motor function. They are also responsible for muscle contraction and cellular movement. {{6 1 0.png}}
What are motor proteins
Motor proteins associated with microtubules. Kinesins play a role in aligning chromosomes during metaphase and depolymerizing microtubules during anaphase of mitosis. Dyneins are involved in the sliding movement of Cilia and flagella. Both proteins are important for vesicle(a small anatomically small sac) transport in the cell, but have opposite polarities; kinesins bring vesicles toward the positive end of the microtubules and dynein bring vesicle toward negative end. This is how they recycle each other
What are kinesins and Dyneins ?
Proteins that act in this way transport or sequester molecules by binding to them. That includes hemoglobin, calcium-binding proteins, DNA-binding proteins. A transport protein, which must be able to bind or unwind its target to maintain steady-state concentrations, is likely to have varying affinity depending on the environment conditions.
What are Binding proteins ? Examples
Proteins found on the surface of most cells that aid in the binding of the cell to the extracellular matrix or other cells. While there are a number of different types of CAMs. They are all integrated membrane proteins.These molecules are classified into Cadherins, integrins, and selectins.
What are Cell adhesion molecules (CAMS) ? What are the three major families?
A group of glycoproteins that mediate calcium-dependent cell adhesion(property of sticking together) . Cadherins often hold similar cell types together, such as epithelial cells. Different cells usually have type-specific Catherine; for example, epithelial cells use E-cadherin while nerve cells use N-cadherin
What are Cadherins ?
A group of proteins that all have two membrane-spanning chains called alpha and beta. These chains are very important in binding to and communication with extracellular matrix. Interns also play a important role in cellular signaling and can greatly impact cellular function by promoting cell division, apoptosis, or other processes. For example integrin aIIb3 allows platelets to stick to fibrinogen, a clotting factor, which causes activation of platelets to stabilize the clot.
What are integrins ? Give an example?
This one is unique because they bind to carbohydrate molecules that project from other cell surfaces. These bonds are the weakest formed by CAMs
What are selectins ?
Also called Immunoglobulin(Ig) are proteins produced B-cells that function to neutralize targets in the body such as toxins and bacteria, and then recruit other cells to help eliminate the threat. Antibodies are Y shaped proteins that are made up of two identical heavy chains and two identical light chains.
What are antibodies ?
When antibodies bind to their target. Also the possible outcomes are
* Neutralizing the antigen , making the pathogen or toxin unable to exert its affect on the body Marking the pathogen for destruction by other white blood cells immediately this marking function is called ( opsonization) Clumping together(agglutinating) the antigen and antibody into large insoluble protein complexes that can be phagocytized and digested by macrophages.
What is an antigen ? Once bonded what are the three possible outcomes?
A process in which cells receive and act on signals. Proteins participate in biosignaling in different capacities, including acting as extracellular ligands, transporters for facilitated diffusion, receptor proteins, and second messengers.
What is Biosignaling ?
<p>A type of passive transport, is the diffusion of molecules down a concentration gradient through a pore in the membrane created by the transmembrane protein. {{16 1 0.png}}</p>
<p>What is Facilitated diffusion ?</p>
<p>Obviously they have no gates and therefore unregulated. This means there will be a net efflux of potassium ions through these channels unless potassium is at equilibrium.</p>
<p>What are ungated channels?</p>
In order for GPCRs to transmit signals to an effector in the cell through a receptor. because also it contains three different sub units
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What is a heterotrimeric G protein?
<p>One method of separating proteins. It works by subjecting compounds to a electric field, which moves them according to their net charge and size. {{27 1 0.png}}As an electrolytic (nonspontaneous) cell, electrophoresis moves charged particles toward their respective oppositely charged electrodes; the larger the particle , the more slowly it migrates.</p>
<p>What is electrophoresis ?</p>
