BIS 2A Lecture Notes - Lecture 22: Peptidyl Transferase, Release Factor, Hydrolysis

59 views4 pages

viridianwallaby406

8 Jun 2018

School

Department

Course

Professor

For unlimited access to Class Notes, a Class+ subscription is required.

BIS2A Lecture 22: Translation and Protein Synthesis

• Translation: mRNA into protein

o Requires ribosome binding site, translation initiation site (start codon) and

translation termination site (stop codon)

• Protein synthesis machinery

o General functions of the translation machinery are the same across species but

the composition of the components are not

▪ mRNA template and open reading frame (ORF), amino acids, ribosomes,

tRNAs, energy, enzymes and small molecules

o Ribosomes catalyze the process of translation

▪ Composed of structural and catalytic rRNAs and protein

▪ Found in cytoplasm of prokaryotes and cytoplasm/endoplasmic reticulum

of eukaryotes

• Mitochondria and chloroplasts also have ribosomes which are

similar to bacterial ribosomes

▪ Disassociated into small and large subunits and only assemble during

initiation of translation

▪ Catalyze formation of peptide bonds between amino acids

▪ Draw structure of ribosome and components of translation

o tRNAs physically pair amino acids with the correct codon

▪ Originally single-stranded RNA molecule that folded on itself and formed

stem loops (base-paired region)

• 3’ ed otais the attahed aio aid

• Loop structure contain the anticodon (complementary to the

codon on the mRNA)

• Draw one

▪ Aminoacyl tRNA synthetases: enzymes that attach the correct amino acid

to the tRNA

• Active site contains tRNA binding site which can recognize

anticodons and allosteric sites that can bind to reactants

• Bind and hydrolyze ATP to form amino acid-AMP bond

• Specific amino acid activated and transferred to tRNA and AMP

released

• Charged tRNA released from the active site

• Draw the process

o Energy source

find more resources at oneclass.com

Unlock document

This preview shows page 1 of the document.
Unlock all 4 pages and 3 million more documents.

Already have an account? Log in

Related Questions

Facts about ribosomes

Indicate whether each of the following statements aboutribosomes is true or false.

1. Ribosomes are composed of tRNA and protein. TrueFalse
2. During translation in eukaryotes, some ribosomes remain free inthe cytoplasm while others attach to protein channels embedded inthe RER. TrueFalse
3. During initiation of translation, the small ribosomal subunitjoins to the mRNA and initiator rRNA, followed by the largeribosomal subunit. TrueFalse
4. When a ribosome first assembles on the mRNA, the initiator tRNAoccupies the A site while the P and E sites are empty.TrueFalse
5. During translation, a charged tRNA first binds to the ribosomeif its anticodon matches the codon in the E site. TrueFalse
6. A peptide bond forms between the amino acid attached to a tRNAin the A site and the growing polypeptide attached to a tRNA in theP site. TrueFalse
7. Uncharged tRNA molecules in the E site are ejected from theribosome. TrueFalse
8. No more than 2 tRNA molecules are bound to a ribosome at anygiven time. TrueFalse
9. During translocation of the ribosome, tRNA molecules move fromthe P site, to the A site, to the E site, and are then ejected fromthe ribosome. TrueFalse
10. During translation, an amino acid attached to a tRNA in the Asite is transferred to a growing polypeptide attached to a tRNA inthe P site. TrueFalse

periwinklemuskrat632

Facts about ribosomes

carmineraccoon103

1. _________________________ is the name of the process that produces proteins using RNA molecules.

a.Transcription

b Translation

c. Replication

d. Mutagenesis

2. The peptide bonding site on the ribosome:

a. A site

b. P site

c. E site

d. D site

3. The name given to the bond formed between two amino acids.

a. Hydrogen bond

b. Double bond

c. Peptide bond

d. Negative bond

4. __________________________ is the movement of the mRNA molecule on the ribosome to open up the A-site for the new incoming amino acid.

a. Transformation

b. Mutation

c. Translocation

d. Initiation

5. What does the term semi-conservative mean.

a. Replication of RNA is semi-conservative, each new strand consists of one old strand of RNA and one new strand of RNA.

b. Replication of DNA is semi-conservative, each new strand consists of one old strand of DNA and one new strand of DNA.

c. Replication of DNA is semi-conservative, each new strand consists of new strands of nucleotides.

d. Transcription of RNA is semi conservative.

6. This molecule functions during protein synthesis to recognize the codon and bring the proper amino acid back to the ribosome for translation.

a. mRNA

b. tRNA

c. rRNA

d. DNA polymerase

7. What is meant by the base-pairing rule.

a. Bases on a single strand of DNA are always found as pairs

b. Adenine always base pairs with guanine; cytosine with thymine

c. Adenine always base pairs with thymine; cytosine with guanine

d. Bases on a single strand of RNA are found in pair.

8. In this step of protein synthesis, amino acids are added to a growing polypeptide chain.

a. Initiation.

b. Elongation.

c. Termination.

d. Transpiration.

9. Three complementary bases found in a mRNA are called ____________________.

a. Anti-codon.

b. Triplet.

c. Doublet.

d. Codons.

10. Which statement best describes the job or function of the messenger RNA.

a. Carries the map of the gene sequence in the form of codons to the cytoplasm

for translation of the protein.

b. It transfers amino acids to the ribosome for protein synthesis.

c. It forms the ribosomes.

d. It helps replicate DNA.

ceruleangnat663

BIS 2A Lecture Notes - Lecture 22: Peptidyl Transferase, Release Factor, Hydrolysis

Get access

Related Documents

BIS 2A Lecture Notes - Lecture 7: Start Codon, Citric Acid Cycle, Release Factor

BIS 2A Final: BIS 2A FINAL

BIOSC-139 Lecture Notes - Lecture 18: Ribosomal Rna, Messenger Rna, Ribosome

Related Questions