Chapter 8: Microbial Genetics Part I
Chapter 8: Microbial Genetics Part I 2420
Popular in Microbiology
Popular in Biology
verified elite notetaker
This 2 page Class Notes was uploaded by Siân L'Roy on Sunday August 21, 2016. The Class Notes belongs to 2420 at Tarrant County College District taught by Mark Pulse in Summer 2016. Since its upload, it has received 21 views. For similar materials see Microbiology in Biology at Tarrant County College District.
Reviews for Chapter 8: Microbial Genetics Part I
Report this Material
What is Karma?
Karma is the currency of StudySoup.
You can buy or earn more Karma at anytime and redeem it for class notes, study guides, flashcards, and more!
Date Created: 08/21/16
Microbial Genetics Part 1 Important characteristics of prokaryotic DNA (deoxyribonucleic acid) o Supercoiled and circular (think of a rubber band); DNA found in the cytoplasm o Single chromosomal copy; multiple copies of plasmid DNA (varies); E. coli up to 18 o Double helix; two antiparallel, complementary strands o Alternating sugarphosphate backbone; sugar (pentose) is bond to one of four nitrogenous bases Adenine (A), Cytosine (C), Guanine (G), and Thymine (T) There are 64 possible different combinations o Purine nucleotides: A and G o Pyrimidine nucleotides: C and T o Complementary strands are held together by hydrogen bonds between AT and C G (basepairing) Longer strands are more stable; two hydrogen bonds with AT (weaker) and three hydrogen bonds with CG (stronger) AGATCGTATGCTTACG TCTAGCATACGAATGC o Phosphate (5’) end and Hydroxyl (3’) end 5’AGATCGTATGCTTACG3’ 3’TCTAGCATACGAATGC5’ o Important in DNA replication and transcription o Double helix can be separated into single strands; process known as denaturing o Genetic Code: 3 nucleotides (codon) encodes for 1 amino acid (Protein formation) Prokaryotic DNA replication is necessary for growth and inheritance of genotype and phenotype common to a species Daughter cells receive one complete copy of chromosomal (and plasmid) DNA from parent DNA replication is: o Bidirectional: Two replication forks moving in opposite directions; faster than unidirectional o Semiconservative: Each daughter cell receives 1 strand from parent and complement copy of that strand DNA replication involves covalently linking 1 deoxynucleotide triphosphate to another o Covalent linkage occurs at the 3’ end via Hydrolysis o Elongation (new strand) occurs from 5’ to 3’; template (original) is read 3’ to 5’ DNA replication is accomplished by the following sequential steps: Microbial Genetics Part 1 o Origin of replication is temporarily denatured by sequence specific proteins; it is an unstable area (DNA replication complex) o Helicase separates and unwinds the DNA helix; like a helicopter, Z form/zipper shaped, and energy dependent o DNA gyrase temporarily breaks the strands to relieve tension caused by being unwound; clips the DNA backbone o Short RNA fragments are synthesized to serve as primers for replication; starting point (DNA primase) o DNA polymerase continuously synthesizes a ‘new’ complement strand from the lead strand Discontinuous synthesis is associated with the lagging strand; initiated by short RNA primers and produces series of broken fragments called Okazaki fragments (not continuous) Fragments are covalently linked together by DNA ligase
Are you sure you want to buy this material for
You're already Subscribed!
Looks like you've already subscribed to StudySoup, you won't need to purchase another subscription to get this material. To access this material simply click 'View Full Document'