Biochemistry of Aging Flashcards
The hydrolysis of amino groups on nucleotide bases can lead to
Changes in genetic info stored in DNA
Causing Mutations or DNA damage
It is the longest stage, and a period of
dramatic physical growth or developmental
change
Adulthood
plays important catalytic, regulatory, redox, and structural roles in proteins
Sulfhydryl group of Cysteine
provide an expendable source of DNA whose gradual loss is of little immediate consequence to the cell.
Telomere
process when amine groups in proteins and nucleotides are exposed to a reducing sugar such as glucose, they may form an adduct
Glycation
possesses the precise geometry needed to bring its side chain carboxyl group into close proximity with the peptide bond involving its α-carboxyl group, at which point they may react to generate a cyclic diamide
Aspartic Acid
contain a conjugated carbon–carbon double bond that can react with the amino group on a neighboring macromolecule
Amadori Products
proposes that these mutations also serve as drivers of the aging process. Simply put, the accumulation of mutated somatic cells must inevitably lead to compromised biologic function that manifests itself, at least in part, as the physical changes we associate with aging
somatic mutation theory of aging
Replacement by hydrolysis of the amino groups on nucleotide bases with ___________ alters the chemical structure of the bases
Carbonyl oxygen
products arising from the combination of precursors - with biologic compounds that contain multiple double bonds such as nucleotide bases and polyunsaturated FA
Adducts
used as biomarkers for the diagnosis of diabetes.
Glycation of hemoglobin and serum albumin
consists of two tripeptides linked by an S-S bond, is then enzymatically reduced to maintain the pool of protectant.
Oxidized glutathione
possess antioxidant properties, which accounts for the popularity of diets that emphasize foods or supplements rich in these compounds to combat ROS and, hopefully, slow aging
Ascorbic Acid and Vitamin E
Guanine will be replaced to form
Xanthine
He proposed the free radical theory of aging
Denham Harmon
individual’s lifespan was reciprocally linked to their basal metabolic rate
Raymond Pearl
Loss of membrane integrity can ____________
Potentially allow proton to leak across, reducing efficiency of ATP generation
They carry a negative charge at physiological pH, which stabilizes protein structures through interactions like salt bridges and hydrogen bonds
Aspartate and Glutamate residues
process where the individual members of the global population of a given biomolecule are degraded and replaced by new synthesis on a continuing, or constitutive, basis to remove damaged lipids, carbohydrates, and proteins
Routine turnover
imbues higher organisms with the ability to selectively eliminate cells that are rendered superfluous by developmental changes, such as those that continually take place during embryogenesis, or which have been damaged beyond repair
Apoptosis
toxic aggregates due to modification of protein’s composition or conformation that cause it to adhere to other protein molecules
Amyloid
most common of source of ROS due to high levels of electron flux and structural complexity render it vulnerable to “leakage” of ROS
Electron Transport Chain
Reactive Oxygen Species display a particularly strong tendency to form
Adducts
for repairing double-strand breaks in the phosphodiester backbone
Ku System
Cytosine will be replaced to form
Uracil
Prominent sources of molecular and cellular damage
Water, Oxygen and Sunlight
Employ prosthetic groups such as flavin nucleotides, iron-sulfur centers, or heme-bound metal ions to assist in generating and stabilizing the free radical and oxyanion intermediates formed during these processes
Redox Enzymes
provides the core around which the apoptosome, a multiprotein complex, coalesces
Cytochrome C
Susceptible Targets of Water inside the cell
Amide Bonds that forms polypeptide chains
Side Chain Amides of the amino acids Asparagine and Glutamine
postulates that aging is a reflection of the cumulative biomolecular damage that results from the continual and inescapable production of ROS.
Free Radical Theory
A weak nucleophile but ubiquitous and high in concentration.
Water (Tubig)
lacks genes encoding the types of surveillance and repair enzymes responsible for maintaining the integrity of nuclear DNA
Mitochondrial Genome
This can lead to the efflux of cytochrome C
Accumulated damage to mitochondrial membranes
Adenine will be replaced to form
Hypoxanthine
refers to those wave lengths of light that lie immediately below the blue end of the visible spectrum
UV Radiation
These are three human genetic diseases whose pathologies include an acceleration of many of the physiologic events associated with aging
Hutchison-Gilford, Werner, and Down syndrome
What is most frequently targeted by water
Side Chain Amides of the amino acids Asparagine and Glutamine
can reduce cysteine sulfenic acids and aberrant disulfides on proteins and form adducts with toxic xenobiotics
Glutathione
a much reduced, vestigial remnant of the genome of the ancient bacterium that was the precursor of the current organelle
Mithochondrial Endogenous Genome
Other biologically relevant bonds that are susceptible to hydrolysis
Ester linkages connecting Fatty Acids to Cognate Glycerolipids
Glucosidic Bonds that link monosaccharide units of Carbs
Phosphodiester bonds that hold polynucleotides together
It is the final stage of life, is signaled by a
resurgence of physical and physiological
change
Old Age
reflects the robustness and durability of an individual’s molecular protection, repair, and replacement mechanisms
Longevity
Peroxidation of Lipids leads to the formation of
Cross linked lipid-lipid and Lipid-Protein adducts
Harmon’s observation that lifespan is inversely related to
Metabolic rate and Respiration
The most prominent mechanisms for repairing damaged proteins target the
oxidized side chain sulfur atoms of cysteine and methionine, and the isoaspartyl groups
This chemical reaction transforms asparagine and glutamine residues into aspartate and glutamate residues
Hydrolysis
Adducts formed with _____________ can be dangerous because if uncorrected they cause mutation generating errors during DNA replication
Nucleotide Bases
It is the lifespan for those who survived
infancy. It does not take into account infant
mortality
Longevity
Maintaining the integrity of the genome begins at
Replication
a ribonucleoprotein that is expressed in stem cells and most cancer cells, but not in somatic cells.
Telomerase
Biologic processes that require enzyme-catalyzed oxidation of organic molecules by molecular oxygen
Hydroxylation of Proline and Lysine
Detoxifications of Xenobiotic by cytochrome P450
Degradation of Purine to Uric Acid
Reoxidation of the prosthetic groups in Flavin
Redox Reactions
These are crucial for enzyme catalysis, regulatory mechanisms and metal ion binding enhancing protein function, stability and interactions in biological processes
Aspartate and Glutamate residues
It is calculated by averaging
overall births, hence influenced by infant
mortality
Life expectancy
Pathways that can be generated from less destructive ROS in living organisms
Fenton Reaction and Haber Weiss Reaction
