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RNA and Proteins

Macromolecules and Ribosomes

Which statement is incorrect about macromolecules? a. Polypeptides are composed of amino acids linked by amide bonds. b. RNA is composed of ribonucleotides linked by phospho ester bonds. c. Carbohydrates polymers are composed of monosaccharides linked by ester bonds. d. RNA is composed of four different monomers. Which is

Initiation of chromosomal DNA replication in a novel bacterium

You are studying the initiation of chromosomal DNA replication in a novel bacterium that grows at 75°C. To this end you have isolated temperature sensitive replication mutants in twelve different proteins/genes derived from this strain. You call these mutations hot1-hot12. Your hope is to use these mutations to identify protein

Human Homeodomain

1. Find a model of a human homeodomain/DNA complex. a. How many models do you find? b. What method of structure determination produced the first of these models? c. View the first model on the list with QuickPDB or your favorite molecular viewer. What secondary structural element(s) (helix, sheet, coil) interact with DNA? d

Galactose represser protein

The galactose represser protein from E. coli has a pI of about 5.9. While purification protocols were being designed, it was found to bind to a Mono-S column at pH values of 7 and below. (Mono-S columns have S-type sulfonic acid groups attached to the resin and are strong cation exchangers.) What is unusual about this observ

Translocation of proteins

A. Explain the experimental results that are seen in the absence of microsomes (Figures 8-10, lanes 1 to 4). B. Using the three criteria outlined in the problem decide whether the experimental results in the presence of microsomes (lanes 5 to 8) indicate that the protein is translocated across microsomal membranes. Explain the

DNA Transcription & Replication

How does transcription differ from DNA replication? How is it the same? What is the role of complementary base-pairing in each? If a section of the DNA strand to be transcribed is CTAATGT, what is the corresponding section of the mRNA? *PLEASE SIMPLIFY*