23 matches pdf. Biochemistry 8th ed - Jeremy M. Berg. Pages Professor Stryer has received many Student Teaching Award, and the Professor's. Amino Acid Sequences Can Be Determined by Automated Edman Degradation. Immunology Provides Important Techniques with Which to Investigate. DedicationAbout the authorsPrefaceTools and TechniquesClinical ApplicationsMolecular EvolutionSupplements Supporting Biochemistry, Fifth.
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Read the latest articles of Biochimica et Biophysica Acta at switunludisftalk.tk, Elsevier's leading platform of Pages Download PDF . Lubert Stryer. PDF | Aditya Mittal and others published MICROBIAL PHYSIOLOGY AND BIOCHEMISTRY. Stryer. Stryer, Biochemistry (4 th Ed.), W. H. Freeman and Co. , NY, Jan August · Biochimica et Biophysica Acta. Abstract | PDF J. S. Pober, V. Iwanij, E. Reich, and L. Stryer . Biochimica et Biophysica Acta (BBA) - Protein Structure (1),
Seventy-five fish were divided into five groups each group in triplicate , and then exposed to 0, 0. At the end of the experiment, plasma and hepatic lipid metabolic biochemical status were analyzed. There were no significant differences in hepatic hormone-sensitive lipase contents between the trichlorfon-treated fish and the controls. Furthermore, electron microscope observations showed rough endoplasmic reticulum dilatation and mitochondrial vacuolization in hepatocytes with trichlorfon exposure.
On the basis of morphological and physiological evidence, trichlorfon influenced crucian carp hepatic pathways of lipid metabolism and hepatocellular ultrastructure, which resulted in lipid accumulation in the liver.
Hepatic lipid accumulation in fish is a common problem in fish farming, and may have an impact on fish growth, resistance to environmental stress factors, disease susceptibility, and survival.
Hepatic lipid accumulation is influenced by a variety of stimuli, such as parasites Paperna , toxins Tanaka et al. Research into lipid accumulation has focused on dietary nutrients imbalance and antifatty liver factor deficiency Liang et al. Excess feeding with high-fat food is a major risk factor Speare Lie et al. Pulla-Reddy and Lokesh showed that dietary fat influenced the anti-oxidative system of the body, which resulted in hepatic lipid accumulation.
There have been some reports on the effects of chemical pesticides on hepatic lipid accumulation Rojik et al. In a review Couch found the most commonly encountered nonspecific liver lesion after pesticide lindane and methoxychlor exposure was fatty change.
In a previous study, Xu et al. Trichlorfon has been widely used as an organophosphorus pesticide in agriculture to control insect pests owing to its relatively low bioaccumulation and short-term persistence Videira et al.
The dosage necessary to eradicate ectoparasites varies from 0. Prokaryotes synthesize polyprenols called bactoprenols in which the terminal isoprenoid unit attached to oxygen remains unsaturated, whereas in animal polyprenols dolichols the terminal isoprenoid is reduced. Saccharolipids describe compounds in which fatty acids are linked directly to a sugar backbone, forming structures that are compatible with membrane bilayers. In the saccharolipids, a monosaccharide substitutes for the glycerol backbone present in glycerolipids and glycerophospholipids.
The minimal lipopolysaccharide required for growth in E. They comprise a large number of secondary metabolites and natural products from animal, plant, bacterial, fungal and marine sources, and have great structural diversity.
Many commonly used anti-microbial , anti-parasitic , and anti-cancer agents are polyketides or polyketide derivatives, such as erythromycins , tetracyclines , avermectins , and antitumor epothilones.
The glycerophospholipids are the main structural component of biological membranes , as the cellular plasma membrane and the intracellular membranes of organelles ; in animal cells, the plasma membrane physically separates the intracellular components from the extracellular environment.
A biological membrane is a form of lamellar phase lipid bilayer. The formation of lipid bilayers is an energetically preferred process when the glycerophospholipids described above are in an aqueous environment. In an aqueous system, the polar heads of lipids align towards the polar, aqueous environment, while the hydrophobic tails minimize their contact with water and tend to cluster together, forming a vesicle ; depending on the concentration of the lipid, this biophysical interaction may result in the formation of micelles , liposomes , or lipid bilayers.
Other aggregations are also observed and form part of the polymorphism of amphiphile lipid behavior. Phase behavior is an area of study within biophysics and is the subject of current[ when? So in an aqueous environment, the water molecules form an ordered " clathrate " cage around the dissolved lipophilic molecule.
They are a major source of energy because carbohydrates are fully reduced structures. In comparison to glycogen which would contribute only half of the energy per its pure mass, triglyceride carbons are all bonded to hydrogens, unlike in carbohydrates. Migratory birds that must fly long distances without eating use stored energy of triglycerides to fuel their flights. They accomplish this by being exposed to the extracellular face of the cell membrane after the inactivation of flippases which place them exclusively on the cytosolic side and the activation of scramblases, which scramble the orientation of the phospholipids.
After this occurs, other cells recognize the phosphatidylserines and phagocytosize the cells or cell fragments exposing them. Acyl-carnitines are involved in the transport and metabolism of fatty acids in and out of mitochondria, where they undergo beta oxidation.
Polyprenol phosphate sugars and polyprenol diphosphate sugars function in extra-cytoplasmic glycosylation reactions, in extracellular polysaccharide biosynthesis for instance, peptidoglycan polymerization in bacteria , and in eukaryotic protein N- glycosylation.
The process of lipid metabolism synthesizes and degrades the lipid stores and produces the structural and functional lipids characteristic of individual tissues. Biosynthesis[ edit ] In animals, when there is an oversupply of dietary carbohydrate, the excess carbohydrate is converted to triglycerides. This involves the synthesis of fatty acids from acetyl-CoA and the esterification of fatty acids in the production of triglycerides, a process called lipogenesis.
Vegetable oils are rich in various polyunsaturated fatty acids PUFA. Lipid-containing foods undergo digestion within the body and are broken into fatty acids and glycerol, which are the final degradation products of fats and lipids.
Lipids, especially phospholipids , are also used in various pharmaceutical products , either as co-solubilisers e. Proteins are very large molecules—macro-biopolymers—made from monomers called amino acids. The side chain "R" is different for each amino acid of which there are 20 standard ones. It is this "R" group that made each amino acid different, and the properties of the side-chains greatly influence the overall three-dimensional conformation of a protein.
Some amino acids have functions by themselves or in a modified form; for instance, glutamate functions as an important neurotransmitter. Amino acids can be joined via a peptide bond.
In this dehydration synthesis, a water molecule is removed and the peptide bond connects the nitrogen of one amino acid's amino group to the carbon of the other's carboxylic acid group. The resulting molecule is called a dipeptide , and short stretches of amino acids usually, fewer than thirty are called peptides or polypeptides.
Longer stretches merit the title proteins. As an example, the important blood serum protein albumin contains amino acid residues. A schematic of hemoglobin. The red and blue ribbons represent the protein globin ; the green structures are the heme groups.
For instance, movements of the proteins actin and myosin ultimately are responsible for the contraction of skeletal muscle. One property many proteins have is that they specifically bind to a certain molecule or class of molecules—they may be extremely selective in what they bind. Antibodies are an example of proteins that attach to one specific type of molecule. Antibodies are composed of heavy and light chains. Two heavy chains would be linked to two light chains through disulfide linkages between their amino acids.
Antibodies are specific through variation based on differences in the N-terminal domain. Probably the most important proteins, however, are the enzymes. Virtually every reaction in a living cell requires an enzyme to lower the activation energy of the reaction. These molecules recognize specific reactant molecules called substrates ; they then catalyze the reaction between them.
By lowering the activation energy , the enzyme speeds up that reaction by a rate of or more; a reaction that would normally take over 3, years to complete spontaneously might take less than a second with an enzyme. The enzyme itself is not used up in the process, and is free to catalyze the same reaction with a new set of substrates. Using various modifiers, the activity of the enzyme can be regulated, enabling control of the biochemistry of the cell as a whole.
The primary structure of a protein consists of its linear sequence of amino acids; for instance, "alanine-glycine-tryptophan-serine-glutamate-asparagine-glycine-lysine-…". Secondary structure is concerned with local morphology morphology being the study of structure. Tertiary structure is the entire three-dimensional shape of the protein.
This shape is determined by the sequence of amino acids. In fact, a single change can change the entire structure.
The alpha chain of hemoglobin contains amino acid residues; substitution of the glutamate residue at position 6 with a valine residue changes the behavior of hemoglobin so much that it results in sickle-cell disease.