Monday, October 22, 2012

Chemistry Of Proteins-4


1- What is the nature of a prosthetic group in a lipoprotein?

 (Lipoprotein is a conjugated protein with lipid as a prosthetic group)

 2- What is the significance of Sakaguchi test?

 (This test is undertaken for the detection of Arginine)

 3- What is the distance traveled per turn in an alpha helix?

 (0-54 nm)

 4- Name an imino acid.

 (Proline, hydroxy proline)

 5-Choose the chromo protein out of the followings-

 Collagen, Keratin, hemoglobin                      

 (Hemoglobin)

 6-Carbonic anhydrase is an example of simple or conjugated protein?

 (It is a conjugated protein, with metal as th prosthetic group)

 7- Name a peptide which acts as an artificial sweetener.

 (Aspartame)

 8- Name the agents which can bring about denaturation of proteins

 (Heat, acids, alkalis, heavy metal salt, UV light, vigorous shaking etc)

 9- Name a tripeptide which acts a reducing agent in the tissues.

 (Glutathione)

 10- Name a peptide which acts as vasoconstrictor

 (Angiotensin-II)

 11- Name the amino acid which is deficient in pulses

 (Methionine)

 12- Choose the odd one out- Collagen, Elastin, Keratin, Histones

 (Histones- The rest three are scleroproteins)

 13- Name two nano peptides

 (Oxytocin, Vasopressin)

 14- Name two globular proteins

 (Hemoglobin, Myoglobin)

 15-Which test should be undertaken for the detection of cysteine in a protein solution?

 (Lead acetate test)

 16-What is the nature of peptide bond- Single, double or partial double bond ?

(Partial double bond)

 17- Out of all the primary amino acids which amino acid gives yellow color on Ninhydrin test?                

 (Proline and hydroxy proline )

 18- Histamine is formed from Histidine by-

 Deamination, decarboxylation or transamination

 (Decarboxylation)

 19- Name two non alpha amino acid

 (GABA, beta Alanine, Delta amino Levulinic acid)

 20- Choose the odd one out-

 Aspartic acid, lysine, Arginine, Cysteine                  

 (Cysteine- Amino acid with uncharged side chain at physiological p H

 21- Choose the odd one out-

Tyrosine, Tryptophan, Threonine                  

 (Tyrosine- non essential Amino acid from the nutritional perspective or threonine if considered non aromatic amino acid)

 22- Name a purely ketogenic amino acid            

 (Leucine)

 23- Name a peptide used as an anticancer drug          

 (Bleomycin)

 24- Name the defense proteins                                    

 (Complement, immunoglobulin)

 25- Choose the odd one out- Silk fibroin, Hemoglobin, Carbonic anhydrase

 (Hemoglobin- The rest are proteins with beta pleated sheet

 26- The proteins with a carbohydrate content > 10 % are called as Mucoproteins- True or false?        

 (True)

 27- The most abundant amino acid in keratin?            

 (Cysteine)

 28- The most abundant amino acid in Collagen—-?    

 (Glycine)

 29- Xanthoproteic test does not specify for—- ?

 Tyrosine, Tryptophan, Serine              

 (Serine)

 30- Give the characteristics of a peptide bond in one line-

 (Rigid, partial double bond, Trans and stable)



31-Name the branched chain amino acids

 (Valine, Leucine, iso Leucine)

 32-Choose the hydrophobic amino acid out of the followings-

 Aspartic acid, Arginine, Serine, Isoleucine

 (Isoleucine)

 33-Which amino acid acts as Methyl group donor?

 (Methionine)

 34- What is the difference between Deamination and Transamination?

(Deamination is the removal of amino group of the amino acid while Transamination is the transfer of amino group from one  donor amino acid to an acceptor keto acid for the formation of a new amino acid)

 35- Out of the 20 amino acids which amino acids participate in the formation of phosphoproteins

 (Serine and Threonine)

 36- Formation of carbamino compound for the transportation of carbon dioxide is a property of amino group, carboxyl group or both groups?

 (Amino group)

 37- Hopkins Cole test is a confirmatory test for which amino acid?

 (Tryptophan)

 38- How many peptide bonds are there in a tripeptide?

 (Two)

 39- The alpha helix is right or left handed?        

 (Right handed)

 40- What is the direction of hydrogen bonds in the beta pleated sheet structure?

 (Perpendicular to the axis)

 41-What is the direction of beta pleated sheets in flavodoxin?

 (Parallel)

 42-Name the most abundant protein in mammals      

 (Collagen)

 43-Name a defect in the primary structure responsible for the causation of a disease

 (Sickle cell disease)

 44-What is the defect in Alzheimer disease?

 (Protein misfolding leading to formation of insoluble protein aggregates)

 45-What is the isoelectric p H of casein?

(4.6)

 46- What is the effect on the solubility of a protein upon denaturation?

 (Solubility decreases upon denaturation)

 47- Name the lipo proteins of biological significance

 (Chylomicrons, VLDL, LDL, HDL)

 48- Which amino acid is lacking in cereals?

 (Cereals lack Lysine)

 49- Which amino acid forms disulphide linkages between two polypeptide chains in oligomeric proteins?                      

 (Cysteine)

 50- Which peptide is used in clinical practice to induce uterine contractions?

 (Oxytocin)


------------------------------------------ Best Wishes: Dr.Ehab Aboueladab, Tel:01007834123 Email:ehab10f@gmail.com,ehababoueladab@yahoo.com ------------------------------------------

No comments: