Cell Biology BI309 Mini-Review 1 Title: Dynein Motor Proteins In order for eukaryotic cells to be motile they use motor proteins that are propelled by ATP. There are three classes of motor proteins; myosin, kinesin and dynein. Dynein is the motor protein to be discussed in detail for this review. Dynein is a large and complex motor protein found in microtubules of cilia and flagella that causes movement due to the conversion of Adenosine Triphosphate(ATP) which is a form of chemical energy to mechanical energy i.e. movement.
For example, the malate can be transported into the mitochondria via the malate shuttle and re-enter the tricarboxylic acid cycle. Then again, cytosolic malate can be oxidized to oxaloacetate, which can be converted to aspartate or glucose [Jones et.al 2000]. Step 5: Hydrolysis of arginine to form ornithine and urea Enzyme Arginase is required in this step. The arginine is hydrolyzed to generate the urea and to change the ornithine. It occurs in liver cells cytosol.
In many cases the association process is a part of biological function as in blood clotting or the formation of muscle fibers. Aggregation of proteins also leads to perturbation of the biological function with sometimes serious physiological consequences as in the formation of cataracts in the lens of the eye or amyloid fibrils associated with Alzheimer’ and other neurological diseases. From a colloid chemistry perspective, protein self-association is a special case of the general problem of colloid stability. There are two important aspects of the protein systems in this respect: first in contrast to colloids in general the system can be obtained in pure form and then represent a true single component. Second the protein has a complex molecular structure and one should expect protein- protein interactions to be highly directional.
Myosin head bind tightly onto the actin at the binding site and forming a temporary cross-bridge. The formation of this cross bridge resulting in the phosphorylation of the ADP and inorganic phosphate in to ATP. This induces a power stroke movement of the myosin head creating a pulling force on the Z lines of the sarcomere and efficiently allowing the two filaments to slide over each other. The sliding of filaments causes the sarcomere to shorten and the skeletal muscle to
Thus, some of the citric acid cycle are intermediates for other important reactions like the biosynthesis of glucose, fatty acids and amino acids. Due to the many functions of the citric acid cycle is also considered to be the "central hub of metabolism". This is because, as most of the absorbed nutrients, the fuel molecules are oxidized ultimately within the Krebs Cycle and its intermediates are used for various biosynthetic pathways. Figuratively, one can look at the citric acid cycle as a roundabout introduce, in which the nutrients (carbohydrates, fatty acids and amino acids) drive in and drive out again at the different locations for the synthesis of other
3. GROWTH AND CELL DIVISION OF PHYTOPLANKTON Phytoplanktons have diversity and are of both the types prokaryotic and eukaryotic. Cell division is the vital process for regeneration. Prokaryotic forms of phytoplankton which comes under domain bacteria divide by basic process of cell division like binary fission. Eukaryotic phytolanktons which comes under domain eukarya are divide by the process of mitosis.
At high concentrations, it can affect the nervous system by preventing cellular respiration, forming complex with iron in the mitochondrial cytochrome enzymes (Locey, 2005). After much research, it is now found to fit the criteria for gasotransmitters, (i) it exists as a gas, (ii) it is permeable to plasma membrane, (iii) it can be synthesised endogenously by enzymes, (iv) it has defined functions at physiological concentrations, and (v) it has specific molecular targets and its effects can be imitated with exogenous applications (Wang, 2002). There have been a lot of evidence documented regarding the therapeutic effects of H2S, mainly in cardiovascular diseases (Elsey, Fowkes & Baxter, 2010). 2.2 Therapeutic effects of H2S H2S is reported to be a vasorelaxant of blood vessels and its effects seems to involve K+ and Ca2+ channels, though uncertain (Hart, 2011). It has also been found that H2S can produce other hypotensive effects such as regulating plasma renin levels (Lu et al., 2010) and inhibiting angiotensin converting enzyme activity in endothelial cells (Laggner et al., 2007).
Acquisitions of these signals by the transferred genes enabled their expression in the host cytosol and sometimes resulted in the replacement of a host gene by a bacterial homolog, a process known as endosymbiotic gene replacement. In a next evolutionary stage, transferred genes acquired sequences encoding targeting signals (e.g., via exon shuffling) that allowed their protein products to be imported into the mitochondrion or the primary plastid. Most proteins targeted to mitochondria and primary plastids carry N-terminal transit peptides that are later removed in the organelle matrix. Mitochondria and primary plastids are surrounded by two membranes. Consequently, their import machineries are composed of two translocons: one for the outer membrane and the other for the inner
(9) stated that several tumors can express FasL, that is considered a mechanism by which tumors can escape from destruction by the immune response. The members of Bcl-2 family are as well a group of important regulatory factors in apoptosis (10) as they play an important role in mitochondria pathway-mediated apoptosis (11). BCL-2 (B-cell lymphoma 2) was firstly known as a gene whose product causes resistance to apoptosis in lymphocytes. Later studies, identified a number of both pro- as well as anti-apoptotic Bcl-2-related proteins
Similar processes are used in other cells to maintain the large surface areas they need to function, such as cells in the gut and lungs. This research relates to biology as it studies the changes in cells required to maintain homeostasis, a state of internal regulation required by all living organisms. This information is not only relevant to biology, but also to the general community as it could be used to better understand and treat macular degeneration, a disease in which vision and light sensitivity is gradually lost. 3.
And the biggest obstacle would be the presence of gallstones. The liver produces hormones and proteins, in addition to cholesterol and affects the way the body grows and heals. It also converts existing amino acids into proteins and creates new amino acids. And it is these proteins that are the building blocks of the hormones,
The repressor is a regulatory protein that binds to the operator and blocks transcription of the genes of an operon. Inducers bind to the repressors and they also regulate gene expression. In the process of identifying the three strains of E.coli, ONPG (ortho-nitrophenyl b-D galactoside) was used as an indicator. ONPG is a substrate that can detect B-galactosidase, and when it does, it turns yellow. Sarkosyl was also a detergent used in the lab to lyse open cells.
Introduction: Enzymes are needed for survival in any living system and they control cellular reactions. Enzymes speed up chemical reactions by lowering the energy needed for molecules to begin reacting with each other. They do this by forming an enzyme-substrate complex that reduces energy that is required for a specific reaction to occur. Enzymes determine their functions by their shape and structure. Enzymes are made of amino acids, it 's made of anywhere from a hundred to a million amino acids, each they are bonded to other chemical bonds.