{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

#4 Filled in Skeleton Notes

#4 Filled in Skeleton Notes - Skeleton 5 notes Hogan Chem...

Info icon This preview shows pages 1–6. Sign up to view the full content.

View Full Document Right Arrow Icon
Skeleton 5 notes Hogan, Chem 130 Lecture notes DNA Replication “It has not escaped our notice that the specific pairing we have postulated immediately suggests a possible copying mechanism for the genetic material”. -James Watson, 1953. I. DNA Replication A. DNA is replicated by enzymes known as: ___________________________ 1. Replication is semiconservative 2. Meselson – Stahl experiment B. Initiation of replication 1. DNA polymerase requires an origin of replication : 2. reaction details C. Replication occurs at replication forks (“eyes”, “bubbles”, theta structures) 1. unidirectional replication: 1
Image of page 1

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Skeleton 5 notes Hogan, Chem 130 Lecture notes 2. bidirectional replication: D. Replication is semi-discontinuous 1. DNA synthesis is unidirectional a. Leading strand: b. Lagging strand c. Okazaki fragments E. DNA synthesis requires a short RNA primer (RNA primase) 1. Number of RNA primers is strand-specific a. Leading strand: b. Lagging strand c. Excision and replacement 2
Image of page 2
Skeleton 5 notes Hogan, Chem 130 Lecture notes II. DNA polymerases A. Arthur Kornberg discovered and enzyme that synthesizes DNA (1957) 1. DNA polymerase I (DNA pol I): a. b. c. 2. Exonuclease activity 1. pol III holoenzyme catalyzes the synthesis of leading and lagging strands 2. The components of the replisome: 3
Image of page 3

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Skeleton 5 notes Hogan, Chem 130 Lecture notes C. Fidelity of replication If a single subunit of pol I is capable of replicating DNA by itself , why does the bacterial cell require a large multi-protein complex composed of >20 polypeptides to replicate the chromosome? DNA replication must occur with great fidelity. Incorrect expression of the information encoded in the genetic material leads to major problems for an organism. 1. Natural error rates in bacteria, i.e. number of mistakes/ 1000 bp replicated: _____ 2. Sources of fidelity: a. dNTP concentrations: b. 2 step polymerase reaction: c. proofreading by Pol I and Pol III d. additional factors III. Termination of replication in E. coli A. Specific sequences in the DNA act as signals:______________________ B. Function of the Tus protein Final thoughts We have focused our discussion of replication on prokaryotes; however, it is important to note that eukaryotic replication is very similar, but far more complex (i.e. the number of proteins involved in the replisome, etc.) 4
Image of page 4
Skeleton 5 notes Hogan, Chem 130 Lecture notes Transcription I. Introduction A. Transcription is the process of synthesizing a RNA polymer from individual NTPs in a DNA directed manner. B. The transfer of the genetic information encoded in DNA through the intermediate molecule, RNA, must occur with great fidelity. Life cannot support unfaithful interpretation of the genetic information.
Image of page 5

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Image of page 6
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern