Medical Biochemistry And Molecular Biology Exam 1

Front 1

involve a deficiency in acid sphingomyelinase—(ASM) – important in degrading membranes in lysosome; Autosomal recessive

Back 1

Neiman Pick Disease

Front 2

Type ?? Neiman Pick Disease associated with neurological tissues and usually causes death within 2-3 years

Back 2

Neiman Pick Type A disorder

Front 3

Type ?? Neiman Pick Disease where symptoms: enlarged spleen, respiratory problems, cardiovascular problems, can live into adulthood

Back 3

Neiman Pick Type B disorder

Front 4

Cholesterol accumulates in late endosomes which also appear expanded. It is “stuck in traffic” and can’t get out of the endosomes

Back 4

Nieman-Pick Type C disorder

Front 5

group of conditions in which fetal hemoglobin synthesis is not terminated at birth but continues into adulthood; Hoogsteen Base Pairing Problems

Back 5

Hereditary persistence of fetal hemoglobin

Front 6

Disease identified in newborns that is caused by a deficiency in the enzyme phenylalanine hydroxylase.
Results in the accumulation of phenylpyruvate (a phenylketone) in the bloodstream.
If untreated, mental retardation will result.
Treated with a low phenylalanine diet.

Back 6

Phenylketonuria

Front 7

Hoogsteen Base Pairing Problems;is a group of conditions in which fetal hemoglobin synthesis is not terminated at birth but continues into adulthood; The condition results from failure to stop transcription of human Gγ- and Aγ-globin genes, leading to elevated levels of fetal hemoglobin. The formation of an intramolecular DNA triple-helical structure located about 200 bp upstream from the initiation site for transcription of the γ-globin genes (between positions −194 and −215) acts as a brake for their expression

Back 7

Hereditary persistence of fetal hemoglobin (HPFH)

Front 8

used to treat metastatic testicular, ovarian, and a wide variety of other cancers, cross-links DNA. Among the serious side effects of cisplatin are bone marrow depletion, severe kidney impairment, and loss of hearing and balance.

Back 8

Cisplatin

Front 9

the first disease demonstrated to be caused by defective DNA repair. Patients are photosensitive and highly susceptible to skin cancers in sun-exposed areas of the body; rates of skin cancer are 2000–5000-fold higher than average. Many patients also have neurological problems.

It's is a rare, autosomal recessive disease that can be caused by defects in any of eight different genes, reflecting the complexity of DNA repair of pyrimidine dimers, the most common damage introduced by exposure to ultraviolet light. Mutations in seven of the genes lead to defects in the initial incision step in nucleotide-excision repair of pyrimidine dimers.

Back 9

Xeroderma Pigmentosum

Front 10

Xeroderma Pigmentosum encode proteins that function as subunits of ???, a general transcription factor that is also required for transcription-coupled DNA repair.

Back 10

TFII-H

Front 11

is an antimetabolite that inhibits ribonucleotide reductase, the key enzyme needed to make deoxyribonucleotides from ribonucleotides. This decreases the concentrations of the dNTPs, inhibiting DNA synthesis, without dramatically altering the pool of rNTPs needed for transcription. It is used primarily against melanoma and myeloproliferative diseases such as chronic myelogenous leukemia; it can be used in combination with radiation therapy that damages DNA, because by lowering pools of dNTPs it can also inhibit DNA repair. The main side effect is myelosuppression, due to the inhibition of DNA synthesis in bone marrow.

Back 11

Hydroxyurea

Front 12

such as coumermycin A1 and novobiocin prevent catalytic activity; they target the ATPase subunits encoded by gyrB.

Back 12

Topoisomerase inhibitors

Front 13

?? such as Nalidixic acid freeze the covalent DNA–protein links; these complexes are lethal if converted into double-strand breaks, as would happen during replication

Back 13

Topoisomerase poisons

Front 14

Defects in mismatch repair cause ???, and they are important in several other cancers. This was initially suggested by the finding that some colon tumors showed frequent mutations in micro-satellites
The primary defect is a mutation in one of the mismatch repair genes.

Back 14

hereditary nonpolyposis colon cancer (HNPCC),

Front 15

inhibit RNA elongation by intercalating into DNA template; enzyme can’t read as bases and fall off

Back 15

Actinomycin D & Acridine

Front 16

inhibits bacterial RNA synthesis and not eukaryotic RNA by binding to the b subunit of the polymerase; used to treat TB

Back 16

Rifampicin

Front 17

blocks Pol II and Pol III (higher concentrations) but NOT Pol I or bacterial RNA polymerase and not eukaryotic polymerases

Back 17

a-amanitin

Front 18

Deletion of one base (circled U) causes a frameshift, resulting in read-through of the correct stop codon (UAA) and usage of a new downstream stop codon (UAG). The longer protein, called Wayne a-hemoglobin, has a higher rate of breakdown and contributes to the pathology of ???

Back 18

alpha-thalassemia

Front 19

A naturally occurring spontaneous mutation in the TBX3 gene is the cause of ???, which manifests itself in abnormal forelimb and apocrine gland development. Tbx3 encodes a T-box transcription factor that is expressed in the mammary bud and other sites of tissue interactions, such as the limb bud

Back 19

Ulnar-Mammary Syndrome

Front 20

The syndrome is inherited as an autosomal dominant trait that is completely penetrant. The disease is due to mutations in the transcription factor TBX5, which is important in the development of both the heart and upper limbs.

Back 20

Holt-Oram Syndrome

Front 21

This receptor accumulates in the ER in this disease; ER accumulated proteins are degraded in cytosol; It is mutated in a common hereditary disease that affects the entire body, causing progressive disability and early death; The standard test for diagnosis is a sweat test which evaluates the level of chloride excreted by the body.

Back 21

Delta F508 CFTR

Front 22

Enzyme deficiencies usually lead to increased accumulation of specific intermediary metabolites in plasma
and hence in urine. Accumulation of ?? in patients with a deficiency in two enzymes leading to
Decreased levels of nucleotides CTP and TTP. Feedback inhibition would normally decrease ?? production.

Back 22

orotic acid; orotate; Orotic Aciduria

Front 23

Elevation of ?? is an indication of damage to muscle. ?? present after a heart attack since it deals with energy production

Back 23

CPK, creatine kinase

Front 24

In a myocardial infarction, there is an increase in CPK2. In addition, total ??? increases and ?? becomes greater than ?? between 12 and 24 h. Increase in ?? is diagnostic of a secondary congestive liver involvement.

Back 24

LDH, lactic dehydrogenase; LDH1; LDH2; LDH5;

Front 25

?? rises slowly but persists after an myocardial infarction

Back 25

HBDH, alpha-hydroxybutyric dehydrogenase

Front 26

The increase of LDH1 and LDH2 within 12–24 h coupled with an increase in CPK2 is diagnostic of ??.

Back 26

myocardial infarction

Front 27

??? can be treated with recombinant factor VIIa. It can be present in circulaing blood without causing harmful effects, because it's inactive until it forms a complex with tissue factor.

Back 27

hemophilia

Front 28

antithrombin III tightly binds and inactivates thrombin. The clinical administration of ?? promotes the association between antithrombin III and thrombin.

Back 28

heparin

Front 29

Plasmin, which exists in circulating blood as plasminogen, is the protease responsible for degrading the fibrin clots. The activator of plasminogen, another protease termed ??? binds with high affinity to the fibrin clot along with plasminogen. The ??-plasminogen-fibrin complex results in proteolytic activation of plasminogen to plasmin, which then begins digesting the fibrin.

Back 29

tissue plasminogen activator (tPA),

Front 30

Two analogs of Vitamin K, ?? and ??), have been shown to inhibit formation of the carboxyglutamate residues of prothrombin and Factors VII, IX and X. The lack of carboxyglutamate residues, and hence binding of calcium, was shown to inhibit the participation of these proteins in the blood coagulation process. This is the basis for using coumarin drugs clinically as anti-coagulants.

Back 30

dicoumarol (I) and warfarin (II),

Front 31

pH of blood

Back 31

pH = pKa + log [HCO3-]/[CO2]

Front 32

usually indicated diabetes; low pH in blood

Back 32

metabolic acidosis

Front 33

Diseases caused by ??? include
Ehlers-Danlos Syndromes
Osteogenesis imperfecta (brittle bone disease)
Scurvy

Back 33

abnormal collagen synthesis

Front 34

??? results from dietary deficiency of ascorbic acid. Ascorbic acid deficiency causes decreased hydroxyproline and hydroxylysine synthesis because prolyl and lysyl hydroxylases require ascorbic acid.
Collagen containing insufficient hydroxyproline and hydroxylysine loses temperature stability and is less stable than normal collagen at body temperature.

Back 34

Scurvy

Front 35

The usual problems are with fragility and hyperextensibility of skin and hypermobility of the joints.The weaknesses result from defects in collagen structure.

Back 35

EHLERS-DANLOS SYNDROME, TYPE IV

Front 36

Michaelis-Menten equation

Back 36

v = Vmax[S] / Km + [S]

Front 37

??? lowers the oxygen affinity of hemoglobin

Back 37

2,3 bisphosphoglycerate (BPG)

Front 38

??? is characterized by Fe3+ rather than Fe2+ in heme, which cannot bind oxygen. Caused by decreased activity of methemoglobin reductase

Back 38

Methemoglobinemia

Front 39

caused by a missense mutation that gives a single amino acid substitution of glutamate to valine at position 6 on the b-subunit of hemoglobin.

Back 39

Sickle Cell Disease

Front 40

most prevalent mutation found in human cancers; it is a transcription factor that regulates the expression of certain target genes

Back 40

p53 tumor suppressor gene

Front 41

Causes Cell cycle arrest since it's a Cyclin-CDK inhibitor; binds PCNA

Back 41

p21

Front 42

Inhibits p53, targets p53 for degradation

Back 42

MDM2

Front 43

Binds bcl-2 and promotes apoptosis

Back 43

Bax

Front 44

?? an autosomal recessive genetic disorder of the secretory processes of all exocrine glands that affects both mucus secreting and sweat glands throughout the body. The protein product of the CFTR gene has been shown to be a cyclic-AMP regulated chloride ion transporter in the plasma membrane. Deltion F508

Back 44

Cystic Fibrosis

Front 45

a single amino acid change (Glu to Val) creates a “sticky” hydrophobic contact point at positions 6, on the outside surface of the hemoglobin molecule. This causes hemoglobin S molecules to associate abnormally with one another, forming the long fibrous aggregates characteristic of this disease

Back 45

Sickle cell anemia

Front 46

characterized by progressive erosion of articular cartilage; considerable evidence suggests a role for dysregulated apoptosis in the disease process

Back 46

Osteoarthritis

Front 47

Disease: a familial form that comes from a mutation in the LDL receptor. It binds cholesterol, but never lets it enter the cells in an organized fashion

Back 47

Hypercholesterolemia

Front 48

Stop codons

Back 48

UAA
UAG
UGA

Front 49

Start codon

Back 49

AUG

Front 50

pH equation/Henderson-Hasselbalch equation

Back 50

pH = pKa + log [proton acceptor/proton donator]

Front 51

Dissociation Constant equation

Back 51

Ka = [H+] [A-]/[HA]

Front 52

How to find pH of blood?

Back 52

pH = pK + log [HCO3-]/[CO2]

Front 53

?? = Km

Back 53

Vmax/2 = Km

Front 54

turnover number equation

Back 54

kcat = Vmax/[E]

Front 55

Free energy equation

Back 55

Delta G = Delta H - T*Delta S

Front 56

Keq = ??

Back 56

Keq = [products] / [reactants]

Front 57

pH = ??

Back 57

pH = -log[H+]

Front 58

Lineweaver-Burk – x vs y plots??
x-intercept = ?
y-intercept = ?

Back 58

1/v versus 1/[S]
-1/Km
1/Vmax

Front 59

coated vesicles mediate vesicle budding from the ER to Golgi (anterograde transport)

Back 59

COPII

Front 60

coated vesicles participate in retrograde transport of proteins from the Golgi to the ER

Back 60

COPI