Proteins Flashcards
Main component of protoplasm
Proteins
In animals, this is more important to life than carbohydrates
Proteins
(9) Essential Amino Acids
H, I, L, K
M, T, W, F
V
histidine, isoleucine lysine, leucine, methionine, threonine, tryptophan, phenylalanine, and valine
(2) Conditional Amino Acids; needed by infants
H, R
Histidine, Arginine
(11) Non-essential Amino Acids
A, R, N, D
E, G, Q
P, S, Y, C
alanine, arginine, asparagine, aspartic acid, glutamic acid, glycine, glutamine, proline, serine, tyrosine, and cysteine.
What happens to a red litmus paper when Casein is heated?
Red turns to blue when in contact with its fumes
What reaction will you get with Lead and Sulfur
Black precipitation
Elements found in Proteins
C, H, O, N, usually S, and sometimes P
The alteration of conformation of proteins thereby decreasing their solubility in water
Denaturation
The only 2 body fluids that does not contain proteins
Normal urine & Bile
A group of nitrogenous substances
Proteins
How many percent does the body consist of Proteins
About 19%; muscle, tissue, skin, hair, and nails are rich in this
The type of linkage that Protein have
Peptide linkage
Building blocks of Proteins
Amino acid
The two groups that Amino Acids have
Amine Group (NH2) & Carboxylic acid Group (-COOH)
A test for proteins or substances that contain peptide linkage
Biuret Test
Reagent and positive result for Biuret Test
Reagent: NaOH + dilute CuSO4
+ result: violet color
Test used to distinguish the presence of benzene ring
Xanthoproteic Test
Reagent and positive result for Xanthoproteic Test
Reagent: conc. HNO3 (Nitric Acid)
+ result: dark yellow color (Thr, Trp, Phe)
CH2 - CH - COOH
| |
🔷 NH2
F, Phe
HO - 🔷 - CH2 - CH - COOH
|
NH2
Y, Tyr
🔷 - CH2 - CH - COOH
\ | |
N NH2
|
H
W, Trp
Test for Tyrosine (Y)or presence of phenolic OH
Million’s Test
Reagent and positive result for Million’s
Reagent: Mercuric Nitrate + Mercuric Nitric
+ result: flesh/red ppt.
Test for Tryptophan (W)
Hopikins’-Cole Test
Reagent and positive result in Hopkins’-Cole Test
Reagent: Glyoxylic acid + cons. H2SO4
+ result: violet ring
Test for Sulfur
Reduced-Sulfur Test
Reagent and positive result for Reduced-Sulfur Test
Reagent: KOH + Pb(CH3 - COO)2 sol.
+ result: black color (Cys, Met)
Test for glycoproteins
Molisch’s Test
Reagent and positive result for Molisch’s Test
Reagent: 5% α-naphtol + 95% ethanol + conc. H2SO4
+ result: violet ring
This protein is soluble in water and can coagulated by heat
Albumin
This protein is insoluble in water but soluble in dilute solutions of neutral salts.
Globullins
Insoluble in water and dilute solution of neutral salt but are soluble in dilute acid and alkali. It can also be coagulated by heat.
Glutelins
The protein is insoluble in water but soluble in 60 – 80% ethyl alcohol.
Prolamines
