A biochemist is attempting to separate a DNA-binding protein (protein X) from other proteins in solutlon. On present. The proteins have the following properties. Protein pl 7.4 3.8 7.9 7.8 M.W. 82,000 21,500 23,500 22,500 DNA Binding? yes yes no yes What type of protein separation technique might she use to most effectively separate: a) protein X from protein A? b) protein X from protein B? E) protein X from protein C?

The figure shows that the average distance between base pairs measured parallel to the axis of a DNA molecule is 3.4 Å. The average molar mass of a pair of nucleotides is 650 g•mol-1. Estimate the length in cm of a DNA molecule of molar mass 5.1x109 4.0 .26 g•mol-1. cm Roughly how many base pairs are contained in this molecule? [4.0 784615 x base pairs CG G C OH TA Thymine Adenine H. H. OH CH2 N-H.......O CH3 H H N……·H–N HLH TA OH 0-P H2C CG G C H. CH2 Guanine H OH Cytosine ... H-N TA AT H' N.....H-N HLH N-H.......O H2C OH H -o. -P3D0 TA 0- OH H. -CH2 (b) The most common structure of DNA, which is a right-handed double helix. The two strands are held together by hydrogen bonds (a) Base-pair formation between adenine (A) and thymine (T) and between cytosine (C) and guanine (G). and other intermolecular forces.

11) Examine the following two DNA sequences. Sequence 1: ATGCGATGCTAGCAT Sequence 2: ATGCGATGATAGCAT If both of these sequences code for proteins, how might the function of protein 2 differ from the function of protein 1? Use the table below for assistance. U C A G บบน UUC UUA UUG CUU CUC CUA CUG U Phe GUUT GUC GUA GUG Leu Leu AUU AUC lle AUA AUG Met or Start Val Ceweg 232 www... UCU UCC UCA UCG CCU CCC CCA CCG ACU ACC ACA ACG C GCU GCC GCA GCG Ser Pro Thr Ala CAU CAC CAA CAG A AAU AAC AAA AAG UAU U UAC C UAA Stop UGA Stop A UAG Stop UGG Trp G Tyr GAA GAG His Gin Asn Lys GAU GAC Asp G c] Glu UGU UGC CGU CGC CGA CGG AGU AGC AGA AGG GGU GGC GGA GGG Cys Arg Ser Arg Gly U C A G U C A G U C A G by Calin me press A) Protein 1 and protein 2 will function exactly the same. B) Protein 1 will be shorter than protein 2, so they will not function the same. C) Protein 2 will be shorter than protein 1, so they will not function the same. D) Protein 2 has a different sequence, so it will function…

A mixture of five proteins are analyzed by MALDI-TOF. Their molecular weigths are 3 kD, 22 kD, 100 kD, 225 kD and 515 kD. A peak appears in the mass spectrum at 33.3 kD. Which protein most likely gave this peak?