Microbiology 302: Exam 3

Front 1

454 pyrosequencing

Back 1

DNA sample is broken into 100 bp ss segments; amplified by pcr; placed on fiber-optic plate. Pulses from the plate correspond to which nucleotide is being added.

Front 2

annealing

Back 2

reformation of DNA after heated denaturation

Front 3

annotation

Back 3

conversion of raw sequence data into a list of the genes present in the genome

Front 4

BLAST

Back 4

basic local alignment search tool

Front 5

blue-white selection

Back 5

uses Xgal (cleave by B-galactosidase, generating blue product);

blue: no inserted DNA
white: DNA inserted

Front 6

codon bias

Back 6

relative proportions of different codons encoding the same amino acid; varies in different organism

Front 7

dideoxy analog

Back 7

has no 3' OH group; thus elongation terminates when analog is added

Front 8

DNA fingerprinting

Back 8

use of DNA technology to differentiation between very closely related organisms

Front 9

EcoR1

Back 9

restriction enzyme; used to cut DNA for genetic engineering

Front 10

gel electrophoresis

Back 10

technique for separation of nucleic acid molecules by passing an electric current through a gel made of agarose or polyacrylamide

Front 11

gene fusion

Back 11

a structure created by joining together segments of 2 separate genes, in particular when the regulatory region of one gene is joined to the coding region of another gene

Front 12

genome assembly

Back 12

ordering of the genome sequence

Front 13

GFP

Back 13

green flourescent protein; marker protein

Front 14

hybridization

Back 14

base pairing of single strands of DNA or RNA from two different, related sources to give a hybrid double helix

Front 15

knockout mutation

Back 15

when cassettes are inserted, the original cells lose their original genes; point to essential genes

Front 16

LacZ

Back 16

reporter gene; blue-white effect

Front 17

modification enzymes

Back 17

enqyme that chemically modifies bases within a restriction enzyme recognition site and thus prevents the site being cut
(typically methylation)

Front 18

ORF (open reading frame)

Back 18

encodes for a protein
*longer than 100 codons
*codon bias

Front 19

probe

Back 19

strand of nucleic acid that a can be labeled and used to hybridize to a complementary molecule from a mixture of other nucleic acid

Front 20

pUC19

Back 20

excellent cloning plasmid
*only 2, 686 bkp
*maintain high number of copies in cell
*easy isolation
*know bp sequence

Front 21

Real time PCR

Back 21

quantifies the rate of replication; the greater the rate, the more DNA was originally present

Front 22

Sanger sequencing

Back 22

adding dideoxynucleotides to DNA sequence; separated by electrophoresis and has marked nucleotide fragments

Front 23

shotgun sequencing

Back 23

random cloning followed by sequencing through overlapping (typically 7-10 replicate sequences per gene)

Front 24

site-directed mutagenesis

Back 24

technique whereby a gene w/ a specific mutation can be constructed in vitro

Front 25

Southern Blot

Back 25

DNA fragments in the gel are denature to yield single strands, transferred to a synthetic membrane; membrane is exposed to labeled probe (of DNA or RNA)

Front 26

vector

Back 26

a self-replicatin DNA molecule that is used to carry cloned genes or other DNA segments for genetic engineering

Front 27

cytochromes

Back 27

proteins containing heme prosthetic groups; undergo oxidation/reduction through loss or gain of a single electron on the iron atom

Front 28

heme

Back 28

center of cytochrome; consists of a porhyrin with iron in the center

Front 29

porphyrin

Back 29

made of four pyrrole rings

Front 30

transferrin

Back 30

host protein that tightly binds iron tightly; restricts access to prokaryotes (who need it for e- transport chain)