Nucleic Acids Nucleosides and Nucleotides
The most important biological role of ribose and 2-deoxyribose is to act as structural components of polymeric RNA and DNA, respectively. Thus, this is an opportune time to shift our attention to the role of 5-carbon furanoses in the structure and formation of nucleosides, nucleotides, and the polymeric nucleic acids formed from the ribo and deoxyribo forms of the nucleotides. However, before we turn our attention to these genetically crucial macromolecules we need to introduce the...
Michael W King PhD Chap 7 Cellular Genetics and Chap 9 Cellular Development
Mike King is a Professor of Biochemistry and Molecular Biology at Indiana University School of Medicine, Terre Haute, and an Executive Member of the Indiana University Center for Regenerative Biology and Medicine. Dr. King is the author editor of 2 books, and 10 book chapters. Dr. King has expertise in both molecular and developmental biological analysis of early embryonic development and limb regeneration, having studied early Xenopus development for over 20 years. With colleagues at Indiana...
Cellular Signaling
In most cases, intercellular communication involves binding of chemical messengers to appropriate receptors. Messengers are often classified on the basis of how far they travel before reaching a target tissue Fig. 4.1 . Autocrine messengers act on the producing cell. An example would be insulin-like growth factor 1 IGF1 , which is produced by cartilage cells and stimulates proliferation of the same chondrocytes. A paracrine messenger acts on neighboring cells. Neurotransmitters are classified...
Thomas D Hurley PhD Chap 3 Enzyme Kinetics
Tom Hurley received his B.S. degree in biochemistry from Penn State University and his Ph.D. degree in biochemistry from the Indiana University School of Medicine. His postdoctoral work was performed at the Johns Hopkins University School of Medicine in biophysics and biophysical chemistry. He joined the faculty at the Indiana University School of Medicine in 1992, where he is Professor in the Department of Biochemistry and Molecular Biology. Dr. Hurley has authored numerous book chapters and...
CLINICAL BOX 51 Free Radicals and Aging
A free radical, such as the superoxide radical shown on the left, is an unstable molecule that has an unpaired electron in its outer shell. These highly reactive molecules can oxidize and damage proteins, nucleic acid and lipids, triggering oxidative stress and cell death. For example, mitochondrial damage caused by free radicals might trigger apo-ptosis. Formation of free radicals can increase for many reasons, including immune cell activation, inflammation, ischemia, infection, cancer, or...
Amino Acids Peptides and Proteins
While hydrogen bonds are relatively weak, most biological materials including proteins, sugars, fats, and nucleic acids are composed of molecules in which the constituent atoms are linked together by covalent bonds. In covalent bonds, two electrons are shared between the bonding orbitals of the joined atoms. These bonds range in enthalpic energy from about 250 to 400 kJ mol with the exact value depending on the atoms involved. For example, carbon-carbon bonds have an average energy of 348 kJ...
CLINICAL BOX 31 Alcohol Sensitivity in East Asian Populations
The majority of beverage-derived ethanol is metabolized by two enzyme systems in the liver alcohol dehydrogenase and aldehyde dehydrogenase. Fthanol l Acetaldehyde I Acetate Alcohol Dehydrogenase Aldehyde Dehydrogenase Both enzymes utilize a coenzyme, NAD , as the electron acceptor in order to catalyze the oxidation of their substrates. Humans possess multiple forms of both enzymes these are termed isoenzymes. Isoenzymes are related gene products that catalyze similar reactions, but do so with...
Photosynthesis
5.4.1 Conversion of light energy to chemical energy The core of photosynthesis is conversion of light energy to chemical energy or energy transduction. Conversion occurs when the energy in a photon of light is transferred to an electron in a light-absorbing molecule e.g., chlorophyll . Electrons excited in this first energy-transduction step photosystem II are then passed through multiple carriers that undergo reversible oxidation-reduction reactions. Multiple reactions allow for a stepwise...
Carbohydrate Synthesis 551 C3 plants
Carbohydrate synthesis requires carbon fixation which is incorporation of carbon dioxide into an organic compound. In C3 plants, carbon fixation occurs in the initial step of the Calvin cycle, a cycle that occurs in the stroma of the chloroplast. As described in Sec. 5.4.2, the stroma also contains the ATP and NADPH required for carbohydrate synthesis. The carbon dioxide required for carbohydrate synthesis enters a leaf through pores called stomata Fig. 5.20 . It then diffuses into mesophyll...
CLINICAL BOX 52 Phytol and Vaccines
In immunology, an adjuvant is a substance that enhances the ability of a vaccine to stimulate an individual's specific and nonspecific immune responses. Adjuvants can increase the efficacy of a vaccine by a variety of actions, including 1 retaining the vaccine in the body or at the site of injection, 2 reducing degradation of the vaccine, and 3 recruiting macrophages and other cells to augment immune responses to a pathogen or associated antigens. Many adjuvants that are presently available can...
Covalent Regulation of Enzyme Activity
There are two basic types of covalent control of enzyme activity reversible and irreversible. An example of irreversible activation is the proteolytic cleavage of proenzymes in the digestive tract that lead to the active forms of trypsin and chymotrypsin. The activation of these proteolytic enzymes outside the cell is critical, as the presence of active enzymes within the cell could lead to the unwanted degradation of cellular components, or to the complete digestion of the contents of the...
Gabi Nindl Waite PhD Chap 10 From Cells to Organisms and Editor
Gabi Waite is Assistant Professor of Cellular and Integrative Physiology at Indiana University School of Medicine, Terre Haute Assistant Professor of Life Sciences at Indiana State University, Terre Haute and Research Professor of Applied Biology and Biomedical Engineering at Rose-Hulman Institute of Technology, Terre Haute. She received her diploma of Biology B.S. M.S. in 1991 and her Ph.D. in 1995 at the University of Hohenheim, Germany. Dr. Waite teaches physiology and pathophysiology to...
CLINICAL BOX 61 In Vivo Labeling of Cells
Cells monitor their environment through receptor proteins embedded in the cell membrane. Receptor proteins have several attached molecules of sugar or oligosaccharide chains protruding into the extracellular space. These oligosaccharide chains or glycans serve as binding points for ligands to the receptor protein. Developing the ability to detect glycans specific to a particular type of receptors or cells in the living patient would be a major advance in diagnosis and therapy. A recent study...
CLINICAL BOX 11 Why Doesnt Your Stomach Digest Itself
Tight regulation of the body's pH around 7.4 is a hallmark of homeostasis, the maintenance of a stable internal environment. This is important since biomolecules including catalytic proteins enzymes have evolved to function best near a neutral pH, say between pH 7 and 8. For example, higher or lower pHs result in abnormal protonation or deprotonation of protein R groups, which often leads to marked changes in the protein's normal function with the result that strong acids and bases are often...
Cell Membrane
From the early days of the microscope, the cell has been differentiated as having an outer boundary membrane the cell or plasma membrane containing a heterogeneous soup cytoplasm and a nucleus. As microscopy has improved, more details have emerged from the cellular morass to be seen as distinct objects. Through study of pathologic cells and experimentation, we have come to learn about the function of these objects called organelles. For instance, a pathologic cell deficient in the organelle...
Taihung Duong PhD
To introduce the receptors on the surface and inside of cells To introduce representative neurotransmitters To explain the pathway of secretory molecules from production to exocytosis To highlight developmental interactions between transmitters and receptors 6.1 Membrane Receptors 147 6.2 Nuclear Receptors 153 WRITE 6.4 Cell Secretion 168 READ and WRITE 6.5 Synaptic Interactions during Development 174 The human body consists of about 100 trillion 100 X 1012 cells and the communication between...
APPLICATION BOX 11 Phospholipid Nanoparticles and Drug Delivery
Nanoparticles formed from materials as diverse as titanium dioxide and phospholipids are highly attractive to biomedical engineers as vehicles to deliver a variety of cosmetics, drugs, and diagnostic materials to targeted sites in the human body. Nanoparticles employed in the pharmaceutical industry are typically formed from elongated biomolecules, such as phos-pholipids, having one hydrophilic end and one hydrophobic end. Molecules having the latter properties are known as amphiphilic also...
James P Hughes PhD Chap 4 Cellular Signal Transduction and Chap 5 Energy
Jim Hughes is a Professor in the Department of Life Sciences at Indiana State University, Terre Haute, IN. He received a M.S. in Biology in 1974 from University of Arizona, Tucson, AZ, and a Ph.D. in Physiology in 1979 from the University of California, Berkeley, CA. From 1979 to 1982, Dr. Hughes was awarded a Postdoctoral Fellowship in Endocrinology at the University of Manitoba, Winnipeg, Canada. Dr. Hughes joined the faculty at Indiana State University in 1982. His research interests...
Taihung Duong PhD Chap 6 Cellular Communication
Taihung Peter Duong is Associate Professor of Anatomy and Cell Biology at the Indiana University School of Medicine, Terre Haute, and Director of the Terre Haute Center. He received a B.A. degree in Biology from Whittier College in 1977 and a Ph.D. degree in Anatomy from the University of California at Los Angeles UCLA in 1989. He completed 2 years in a postdoctoral fellowship in neuroanatomy at the UCLA Mental Retardation Research Center before joining the faculty at the Indiana University...