micro chap 8

Missense

----- mutation: different amino acid Resulting protein may only partially function Termed leaky

Intercalating agents

------ cause frameshift mutations Flat molecules that intercalate (insert) between adjacent base pairs in DNA strand Pushes nucleotides apart, produces space Causes errors during replication If in template strand, a base pair added to synthesized strand If in strand being synthesized, a base pair deleted Often results in premature stop codon

Point mutation

------ is change of a single base pair

Vertical gene transfer:

------- Occurs during reproduction between generations of cells.

interclating agents

------- are plant molecules that insert between bases pairs and cause mutations

Horizontal gene transfer:

--------- is The transfer of genes between cells of the same generation.

Nonsense

-------mutation: Specifies stop codon Yields shorter protein

Silent

-------mutation: wild-type amino acid

Base substitution

------most common mutation. Incorrect nucleotide incorporated during DNA synthesis

1. Mismatch Repair 2. unmethylated 4. Methylation , unmethylated 5. DNA polymerase, DNA ligase

1. --------Fixes errors missed by DNA polymerase 2. Enzyme cuts sugar-phosphate backbone of the ------ group 3. Another enzyme degrades short region of DNA strand 4. ------of DNA indicates template strand ( old strand),this process takes time, so newly synthesized strand is ----- 5. ---- and ----- make repairs

1. Induced 2. mutagen 3. mutagens

1. -----mutations result from outside influence 2. Agent that induces change is ---- 3. Geneticists may use ------ to increase mutation rate Two general types: chemical, radiation

1. DNA polymerase 4. DNA replication 5. proofreading, mismatch repair

1. For the repair mechansim in nucleotide incorporation, During replication,-------- sometimes incorporates wrong nucleotide 2. Mispairing slightly distorts DNA helix 3. Recognized by enzymes 4. this Mutation can prevented by repairing before ------ 5. What are the Two mechanisms of repairing?

1. number of nucleotides 2. one codon, location within protein 3. frameshift mutation 4. stop codon 5. Knockout mutation

1. In sponataneous mutation, if there is Deletion or addition of nucleotides, the Impact depends on ------- 2. Three pairs changes ------. there will be one amino acid more or less. The Impact of this depends on 3. the deletion of One or two pairs yields ----- 4. In spontaneous mutation Different set of codons translated results in premature ----- 5. Shortened, nonfunctional protein = ------

1. conjugation 2. Sex pilus

1. in ------- F plasmid of E. coli F+ cells have, F- do not Encodes proteins including F pilus 2. ------Brings cells into contact 3. Enzyme cuts plasmid, and Single strand transferred 4. Complementary strands synthesized Both cells are now F+

1. Chromosomal DNA 2. chromosom and plasmid 3. F plasmid 4. reversible 5. small piece of chromosome is removed with F plasmid DNA 6. replicon 7. Hfr cell 8. with genes on one side of origin of transfer of plasmid (in chromosome) 9. recipient cell 10. Chromosome 11. F- since incomplete F plasmid transferred

1. in conjugation, -------- is transfer less common 2. Involves Hfr cells which is a combination of --------(high frequency of recombination) 3. -----is integrated into chromosome via homologous recombination 4. this Process is ------- 5. F' plasmid results when ------- 6. F' is ----- 7. ----- produces F pilus 8. Transfer begins ----- 9. Part of chromosome is transferred to ----- 10. ------usually breaks before complete transfer (full transfer would take ~100 minutes) 11. Recipient cell remains --------

Base analogs

1. in indudced mutations ----- resemble nucleobases Have different hydrogen-bonding properties Can be mistakenly incorporated by DNA polymerase

1. Conjugation: 2. Conjugative plasmids 3. E. coli

1. in------- DNA transfer between bacterial cells, it Requires contact between donor, recipient cells 2. direct their own transfer ( Replicons) 3. F plasmid (fertility) of -----most studied ( plasmids can be transferred and this is how drugs can get resistant) 4. the plasmid is double stranded

6. DNA polymerase

6. Proofreading by -----. it Verifies accuracy Can back up, excise nucleotide, (cut the worng one and put the right one) Incorporate correct nucleotide. Very efficient but not flawless

1. chemicals that modify nucleobasis 2. adds alkyl groups to nucleotides 3. Nucleotide substitution

Alkalyting agents 1. Chemical agent: ------ 2. Action: ------ 3. Result: -------

horizontal gene transfer

Another mechanism of genetoc change is ----------which is done by three mechanisms Transformation: naked DNA uptake by bacteria Transduction: bacterial DNA transfer by viruses Conjugation: DNA transfer between bacterial cells

silent, missense, nonsense MUTATION

Base substitution leads to what three possible outcomes?

1. intercalating agent 2 insert b/w base pairs 3.addition or subtraction of nucleotides

Chloroquine, used to treat malaria, 1. Chemical agent: ------ 2. Action: ------c 3. Result: -------

1. intercalating agent 2 insert b/w base pairs 3.addition or subtraction of nucleotides

Ethidium bromide, Likely carcinogen 1. Chemical agent: ------ 2. Action: ------ 3. Result: -------

Transduction:

IN ----- transfer of genes by bacteriophages ( VIRUSES)

Generalized transduction:

In ------ there is 1. Rare error: during phage assembly 2. Transfer of DNA to new bacterial host

2-amino purine

Induced mutation -----, a base analog, resembles adenine, often pairs with cytosine

5-bromouracil

Induced mutation ------, a base analog, resembles thymine, often base-pairs with cytosine

Ultraviolet irradiation

Induced mutation ----------forms thymine dimers ( two Ts side by side) Covalent bonds between adjacent thymines Cannot fit into double helix; distorts molecule Replication and transcription stall at distortion Cell will die if damage not repaired Mutations result from cell's SOS repair mechanism

1.X rays 2. lethal deletions 3. nucleobases

Induced mutation 1. -------cause single- and double-strand breaks in DNA 2. if the Double-strand breaks, it often produce ------ 3. X rays can alter------

1. Base analogs 2. resembles thymine, often base-pairs with cytosine 3. Nucleotide substitution

Induced mutation 5-bromouracil 1. Chemical agent: ------ 2. Action: ------ 3. Result: -------

UV and Xrays

Induced mutation what two types of radiation mutation are there?

1. chemicals that modify nucleobasis 2. converts cytosine to uracil 3. adenine 4. Nucleotide substitution

Nitrous acid (HNO2 1. Chemical agent: ------ 2. Action: ------ 3. Base-pairs with----- instead of guanine 4. Result: -------

base-pairing properties

Some chemicals modify nucleobases. they Change -------

Transformation

in ------ 1. Recipient cell must be competent Most take up regardless of origin Some accept only from closely related bacteria (DNA sequence) Process tightly regulated - do not need a living organism to have a gene transfer

UV, and Xrays

induced mutation Radiation mutation has what two types? Ultraviolet irradiation forms thymine dimers Covalent bonds between adjacent thymines Cannot fit into double helix; distorts molecule Replication and transcription stall at distortion Cell will die if damage not repaired Mutations result from cell's SOS repair mechanism X rays cause single- and double-strand breaks in DNA Double-strand breaks often produce lethal deletions X rays can alter nucleobases

5. are not using it, so they lose it 7. narrow 8. Gram- and Gram+ 9. Resistance plasmids (R plasmids): 10. R genes and RTF (resistance transfer factor, whiic Codes for conjugation) 11. broad

the mobile gene pool 1. Plasmids found in most Bacteria, Archaea and Some Eucarya 2. Usually dsDNA with origin of replication 3. Generally nonessential; cells can be cured 4. Few to thousands of genes - 5. Low-copy-number, One or a few per cell- this means that they ------- 6. High-copy-number Many, perhaps 500 7. Most have a -----host range ( Single species) 8. Some broad host range. those Includes ----- 9. ------- are Resistance to antimicrobial medications, heavy metals (mercury, arsenic). Compounds found in hospital environments 10. r plasmids have two parts ---- and ----- 11. Rplasmids are Often -----host range 12. Normal microbiota can transfer to pathogens

chemical mutagens , radiation mutagens

two types of induced mutations are ------

Specialized transduction: specific genes (Chapter 13) Generalized transduction: any genes of donor cell

what are the 2 types of transduction?

base substitution point

what are the two most common type of spontaneous mutations?