Biochemistry Flashcards
farbar’s ds., which enzyme deficient?
ceramidase enzyme
c/f– small joint pain
Tangier’s ds., which metabolism is defective?
orange colored tonsils– pathognomic
cholesterol metabolism defective
Km high in which of them, Hexo or Glucokinase?
Glucokinase
low in hexokinase
(Km direcetly proportional to 1/ affinity)
hexokinase and glucokinase belongs to which group of enzymes?
Transferase
all enzymes are proteins except?
Ribozymes (RNA with enzyme activity)
LDH 1,2 AND 5 LOCATIONS?
LDH1- HEART
LDH2- RBC
LDH5- LIVER
BLOOD- LDH2> LDH1
MI- LDH1> LDH2
FLIPPED PATTERN OF LDH SEEN IN?
Myocardial infarction
tryptophan has which type of ring in its structure?
Indol ring
Tryptophan—Serotonin (5 HIAA)—- Melatonin (HIAA)
just remember this..
60 mg of tryptophan give rise to 1mg of niacin (vit B3)
Tryptophan to niacin needs which vitamin?
Vit B6
B6 def.– increase xanthurenic acid and decrease niacin
pellagra seen in which vit def.?
Niacin (b3) def.
maize diet (staple diet)
just remember—
carcinoid syndrome
24 hour urinary HIAA increased
most of tryptophan——-serotonin —- increase HIAA
but Niacin will be decreased.—- pellagra symptoms
c/f– endocardial fibrosis
flushing
hartnup ds., which defect?
AR
absorption of tryptophan and neural AA in intestine and renal tubule is defective
just remember…
tryptophan absorb maximum light at 260-280 nm
what is atkin’s diet?
Low calorie and low carb diet
just remember..
insulin removes phosphate from enzymes and decrease cAMP
OH has tendency to attach with?
phosphate
3 AA with OH group?
Tyrosine
Threonine
Serine
just remember…-
all monosaccharides are reducing sugar as they have free functional group
Imp- Reducing sugar gives Benedict’s test positive in urine sample
Normal color- Blue
Highest sugar content gives brick red color
color changes- viBGYOR
pyq- Benedict’s test is semiquantitative test.
what are enantiomers?
mirror images of each other
e.g., D and L glucose
OH orientation at panultimate carbon (5th carbon)
Note- all carbs in our body are found in D forms only
what is epimerism?
OH orientation at other than panultimate carbon.
IMP— e.g., – Glucose and Mannose at C2
Glucose and Galactose at C4
what is Anomerism?
dietary fibers reduce which thing?
total cholesterol and LDL
dec. post prandial blood glucose
make bulk of feces
Mucopolysaccharides (GAGs) made up of?
acidic sugar (negative charge) + amino sugar (positive charge)
e.g.- Hyaluronic acid (no sulphate)— imp.— found in synovial fluid and vitreous humour—–responsible for wound healing
Keratan sulphate– responsible for transparency of cornea
– Has no acid (COOH)
– Has no uronic acid
Heparin
Heparan sulphate
chondroitin sulphate
dermatan sulphate
Mucopolysaccharidosis (MPS) c/f?
these are lysosomal storage ds.—- all are AR except hunter’s ds.— XR
MPS 1 H- HURLER DS.— COMPLETE IDURONIDASE ENZYME DEF.– Mental retrdation present
MPS 1 S- Scheie ds.– partial iduronidase def.— no mental retardation
MPS 2- Hunter ds.– Iduronate sulfatase def.
- no corneal clouding– no vision issue
MPS 3- SANFILLIPO—Most common
3 IRREVERSIBLE ENZYMES OF GLYCOLYSIS?
- hexokinase
- PFK— rate limiting enzyme
- Pyruvate kinase
just rememer…
all kinases are transferase
all kinase require Mg2+ as cofactor
if kinase is involved in any reaction, ATP is used or produced.
In aerobic glycolysis, net gain of ATP?
7
IN ANAEROBIC GLYCOLYSIS, NET ATP GAIN?
2 ATP only
ATP produced by them:
NADH, FADH,NADPH
NADH- 2.5 ATP
FADH- 1.5 ATP
NADPH- 0 ATP
JUST REMEMBER..
IF KINASE PRODUCES ATP, THIS IS K/A SUBSTRATE LEVEL PHOSPHORYLATION.
Enolase enzyme is inhibited by?
NaF— used for blood glucose estimation
most common enzyme def. leading to hemolytic anemia?
G6PD def., lactate high
2nd most common enzyme def., leading to hemolytic anemia?
Pyruvate kinase def., Lactate is low
exercise intolerance and low lactate levels, diagnosis?
PFK enzyme def.— Type 7 glycogen storage ds.
1 acetyl coA prodcues how many ATPs through kreb’s cycle?
10 ATP
so, 2 produces 20 atp
Cofactor for oxidative decarboxylation?
B1
cofactor for NADH?
B3
FADH cofactor?
B2
CoA, cofactor?
B5
ETC complex 1 name?
NADH CO Q Reductase
inhibitor of complex 1?
RotenONE
Piercidin
just remember?
if removing H== oxidation
if adding H– Reduction
inhibitor of complex 3?
BAL (British Antilewisite)
used in As/Ag poisoning
Antimycin (chemical used in fishery)
Phenformin (not used nowadays— cause lactic acidosis)
Metformin
inhibitor of complex 4?
CN (cyanide)
CO (carbon mono oxide )
H2S
Azide
inhibitor of complex 2?
Malonate
Carboxin
TTFA
inhibitor of complex 5?
Oligomycin==== inhibit F0 (ADP TO ATP conversion)
uncouplers of ETC?
any compound which cause H+ ion leakage via Inner mitochondrial membrane.
Natural Uncouplers:
Thermogenin=== have F1 but no F0
Thyroxine
Long chain FA
Unconj. bilirubin
other:
2,4 Dinitrophenol (DNP)
Dinitrocresol
rate limiting enzyme of HMP shunt?
G6PDehydrogenase
HMP SHUNT occur in?
Cytosol
to detect B2 def., we measure which enzyme activity in rbc?
Glutathion reductase
Von gierke’s ds., which enzyme def.?
Glucose 6 Phosphatase def.
C/f- muscles are not affected as they lack this enzyme already
fasting hypoglycemia (severe)
hepatomegaly
no gluconeogenesis
Kidneys are enlarged
Pompe’s ds., which enzyme def.? Type 2 GSD
acid maltase def.
C/f- hypertrophic cardiomyopathy
Cori’s/ Forbe’s/Limit dextrinosis ds., which enzyme def.? Type 3 GSD?
DEBRANCHING Enzyme def.
C/f—- abnormal glycogen stored
fasting hypoglycemia
hepatomegaly
myopathy
cures itself—– by the puberty age
Type 4 GSD– Anderson ds., which enzyme def.?
Branching enzyme def.
C/f- amylopectin like abnormal glycogen accumulate
death occur by 4 yrs
Type 5 GSD== Mc Ardle’s ds.?
Muscle phosphorylase def.
C/f— exercise intolerance- Rhabdomyolysis– burgendy color urine
low lactic acidosis
Type 6 GSD, Her’s ds?
Liver phosphorylase def.
c/f— mild symptoms
activator of glycogen phosphorylation in muscle?
Calcium
Gluconeogenesis occur in?
Cytoplasm and Mitochondria
not substrate for gluconeogenesis?
pure ketogenic amino acid=== Leucine, Lysine
Glucose 6 phosphatase present in?
SER (smooth endo reticulum)
MC FA synthesis?
palmitic acid
Rothras test is used for?
Ketone bodies detection
gives purple color
Thiophorase is absent in which organ?
Liver
can synthesis ketone bodies but can not utilize ketone body due to this enzyme def.
alpha oxidation takes place in?
Endo reticulum and peroxisome
REFSUM DISEASE?
peroximal disorder (impaired alpha oxidation of branched chain FA)
e.g, Phytanoyl coA
symptoms- retinitis pigmentosa, Icthyosis, Peripheral neuropathy
omega oxidation occurs in?
SER
ZELL WEGER SYNDROME (cerebro hepato renal)?
defect in peroximal function
VLCFA oxidation is altered (it accumulates)—PYQ,
alpha oxidation also affected (branched chain FA)
symptoms- seizures, mongloid face
beta oxidation of odd chain FA
PROPIONIC ACID (PROPIONYL coA)
How HDL works?
by making bad cholesterol into cholesterol ester (reverse cholesterol transport) with help of LCAT enzyme (lecithin cholesterol acyl transferase)
Apo A1 is activator of this enzyme.
DEF.- if partial– Fish eye ds. (corneal opacity)
NO RUM disease– ESRD+ Corneal opacity
All sphingolipoitosis (LSD)…
all have MR– except Gaucher’s ds.
all are AR– except Fabry’s ds.
All have cherry red spot except Gaucher and Fabry’s ds’
basic AA are?
more basic—Arginine> Lysine> Histidine
In electrophoresis, movement depends on?
charge, size, shape —- all of them
Acidic AA are?
aspartic acid, glutamic acid
Amino acid which are polar with ccharge?
Basic AA
His
ARG
LY
ACIDIC AA
ASP
GL
aromatic aa ?
phenylalalnine, tyrosine,
Phenylketonuria, which enzyme def.?
Phenylalanine hydroxylase
Formation of GLUTAMATE?
Alanine give NH3 group to alpha- ketoglutarate to form Glutamate.
Which 3 AA does not show transamination?
Po Ly Thene
Proline
Lysine
Threonine
other 17 AA shows transamination
In Urea cycle defect/ hyperammonimea, which intermediate of kreb cycle will be depleted?
Alpha- ketoglutarate
connecting link between kreb cycle and urea cycle?
Fumarate
connecting AA between Kreb cycle and Urea cycle?
Aspartate
difference between Hyperammonemia Type 1 and 2?
in Type 2 (OTC def.)– Oroticaciduria
in Type 1 (CPS 1)– normal orotic acid
Urea C AND N atoms origins?
C= CO2
N= NH3
N= Aspartate
Helicase funciton?
seperate ds DNA
use ATP
produce supercoiling
Topoisomerase function?
Topo 1– cut one strand
Topo 2– cut both strands
remove supercoiling
NOTE=== In prokaryotes, DNA gyrase in place of topo…
Primase fucntion?
synthesise primer
one primer for leading strand (synthesis occur continuously)
multi primer for lagging stand (synthesis in fragments)
DNA POLYMERASE 3 function?
complete leading strand (form DNA)
small fragment on lagging strand— c/a OKAZAKI fragment
DNA POLYMERASE 1 function?
remove primer in 5’ to 3’ direction from both leading and lagging strands
AND FILL THE GAP ON LAGGING STRAND
small portion of DNA is lost after each replication——TELOMER (TTAGGG)
DNA LIGASE FUNCTION?
act only on lagging strand and join the fragments
what is Heyflick limit?
depending on telomer, cell can divide upto 40-60 times
post transcriptional modification of mRNA?
- CAPPING– occur at 5’ end– it helps to initiate translation (protein synthesis)
- poly A tail attachment at 3’ end AAUAAA (signal sequence) ==== stabilize RNA and help in exit from Nucleus
- SPLICING— removal of intron— DONE BY SnRNA
