BIOB12H3 Lecture Notes - Lecture 4: Asepsis, Molecular Cloning, Microbiological Culture

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scarletwallaby454

10 Aug 2017

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Laboratory 4a: preparation of competent e. coli cells and transformation with a plasmid containing an insert. You will be provided with log phase xl1blue e. coli and you will treat with cacl2 to make the cells competent to take up a plasmid. You will then transform the cells with an unknown plasmid dna, and plate the cells on selective agar medium containing the antibiotic ampicillin (which you made last week). In lab 4b you will isolate plasmid dna from the e. coli cells. In subsequent laboratories, you will carry out restriction endonuclease digests on these plasmids and as a class construct a restriction map. This plasmid is the vector pbluescript with a dna fragment inserted at the ecori site: you will determine the size of the insert and map the restriction sites in this insert. The restriction map of pbluescript is shown below: In this laboratory, you will make e. coli competent (capable) to take up the unknown plasmid.

Related Questions

1. We can construct our gene library by cloning the PstI fragments into either plasmid pBR322 or phage lambda. Which one should we choose and why?

2. Suppose we want to insert the PstI fragments into the Bam HI site within the gene for tetracycline resistance (tet^r) in plasmid pBR322. If both of these restriction enzymes produce cohesive ends, how can this be done?

3. After transforming E.coli with the plasmids, how can we identify the cells that contain a chimeric plasmid (containing DNA insert)?

4. If a million tetracycline-sensitive, ampicillin-resistance clones are grown on nutrients agar plates, how are we going to detect the rare clone or clones that carry the gene for protein P?

5. After selecting a clone carrying the gene for protein P, its ells are propagated to high density in nutrient broth. The chimeric plasmid (with an insert of the gene for protein P) is then extracted and purified from the rest of the cellular DNA. How can we now isolate the gene from the plasmid?

6. How can we demonstrate that the gene we have isolate is indeed the one for protein P?

lemonrat870

View/perform/read ALL THREE of the following prior to answeringthe questions.

http://highered.mcgraw-hill.com/olcweb/cgi/pluginpop.cgi?it=swf::535::535::/sites/dl/free/0072437316/120078/micro10.swf::Stepsin Cloning a Gene (Links to an external site.)

http://www.discoverbiotech.com/wiki/-/wiki/Main/Applications ofCloning (Links to an external site.)

http://www.wiley.com/college/boyer/0470003790/animations/cloning/cloning.htm(Links to an external site.)

Skip to question text.

From the list below, which of the following is the most logicalsequence of steps for splicing foreign DNA into a plasmid andinserting the plasmid into a bacterium?
I. Transformbacteria with recombinant DNA molecule
II. Cutthe plasmid DNA using restriction enzymes
III. Extractplasmid DNA from bacterial cells
IV. Hydrogen-bondthe plasmid DNA to nonplasmid DNA fragments
V. Useligase to seal plasmid DNA to nonplasmid DNA

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Plasmids (or vectors) are important in biotechnology becausethey are

a vehicle for the insertion of recombinant DNA intobacteria.

surfaces for respiratory processes in bacteria.

recognition sites on recombinant DNA strands.

surfaces for protein synthesis in eukaryotic recombinants.

proviruses incorporated into the host DNA

Flag this Question

Plasmids are put into bacterial cells by

restriction enzymes

DNA ligase

binding of cohesive sticky ends

transformation

Flag this Question

Restriction enzymes usually

cut donor DNA evenly so smooth edges result

cut donor DNA but do not affect plasmids

make staggered cuts at specific sequences in DNA in both donorDNA and plasmid

are used in ligating plasmids into bacterial host cells

more than one of the above

Flag this Question

After combining DNA fragments in a cloning experiment, ___ isused to covalently join the DNA segments.

Restriction enzyme

DNA Ligase

Reverse transcriptase

DNA polymerase

Helicase

Flag this Question

It is theoretically possible for a gene from any organism tofunction in any other organism. Why is this possible?

All organisms have ribosomes.

All organisms have the same genetic code.

All organisms are made up of cells.

All organisms have similar nuclei.

All organisms have transfer RNA.

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Skip to question text.

Assume that you are trying to insert a gene into a plasmid andsomeone gives you a DNA sample cut with restriction enzyme X. Thegene you wish to insert from the given sample has sites on bothends for cutting by restriction enzyme Y. You have a plasmid with asingle site for Y, but not for X. Your strategy should be to

cut the plasmid with restriction enzyme X and insert thefragments cut with Y into the plasmid.

cut the plasmid with enzyme X and then insert the gene into theplasmid.

cut the DNA again with restriction enzyme Y and insert thesefragments into the plasmid cut with the same enzyme.

cut the plasmid twice with restriction enzyme Y and ligate thetwo fragments onto the ends of the human DNA fragments cut withrestriction enzyme X.

insert the fragments cut with X directly into the plasmidwithout cutting the plasmid.

Flag this Question

Which of the following is/are false in regard to expressionplasmids (also called expression vectors)?

They are used to make proteins using a cloned gene.

They contain a promotor.

They are the first plasmid type used to clone a gene.

They contain a terminator.

More than one of the above is false.

Flag this Question

What is NOT a potential problem(s) associated with usingbacteria containing a cloned eukaryotic gene (e.g. a human gene) toproduce a functional protein?

If the eukaryotic gene contains introns the bacteria will notremove them and the resulting amino acid sequence will be differentthat that made by a eukaryote.

The bacteria may not fold the protein correctly.

The bacteria may degrade the protein.

All of the above are potential problems.

Flag this Question

Cloning allows for production of proteins in much larger amountsthan occurs in the cells from which the gene is isolated.

True

False

Flag this Question

Question 111 pts

Gene cloning is used to do all of the following except

Make insulin

Making genetically identical animals (e.g. Dolly thesheep)

Make vaccines

Perform Gene Therapy

Making genetically engineered plants

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In your

rubyhedgehog47

View/perform/read ALL THREE of the following prior to answeringthe questions.

http://highered.mcgraw-hill.com/olcweb/cgi/pluginpop.cgi?it=swf::535::535::/sites/dl/free/0072437316/120078/micro10.swf::Stepsin Cloning a Gene (Links to an external site.)

http://www.discoverbiotech.com/wiki/-/wiki/Main/Applications ofCloning (Links to an external site.)

http://www.wiley.com/college/boyer/0470003790/animations/cloning/cloning.htm(Links to an external site.)

Skip to question text.

Flag this Question

Plasmids (or vectors) are important in biotechnology becausethey are

a vehicle for the insertion ofrecombinant DNA into bacteria.

surfaces for respiratoryprocesses in bacteria.

recognition sites onrecombinant DNA strands.

surfaces for protein synthesisin eukaryotic recombinants.

proviruses incorporated intothe host DNA

Flag this Question

Plasmids are put into bacterial cells by

restriction enzymes

DNA ligase

binding of cohesive stickyends

transformation

Flag this Question

Restriction enzymes usually

cut donor DNA evenly so smoothedges result

cut donor DNA but do notaffect plasmids

make staggered cuts atspecific sequences in DNA in both donor DNA and plasmid

are used in ligating plasmidsinto bacterial host cells

more than one of theabove

Flag this Question

After combining DNA fragments in a cloning experiment, ___ isused to covalently join the DNA segments.

Restriction enzyme

DNA Ligase

Reverse transcriptase

DNA polymerase

Helicase

Flag this Question

It is theoretically possible for a gene from any organism tofunction in any other organism. Why is this possible?

All organisms haveribosomes.

All organisms have the samegenetic code.

All organisms are made up ofcells.

All organisms have similarnuclei.

All organisms have transferRNA.

Flag this Question

Skip to question text.

cut the plasmid withrestriction enzyme X and insert the fragments cut with Y into theplasmid.

cut the plasmid with enzyme Xand then insert the gene into the plasmid.

cut the DNA again withrestriction enzyme Y and insert these fragments into the plasmidcut with the same enzyme.

cut the plasmid twice withrestriction enzyme Y and ligate the two fragments onto the ends ofthe human DNA fragments cut with restriction enzyme X.

insert the fragments cut withX directly into the plasmid without cutting the plasmid.

Flag this Question

Which of the following is/are false in regard to expressionplasmids (also called expression vectors)?

They are used to make proteinsusing a cloned gene.

They contain a promotor.

They are the first plasmidtype used to clone a gene.

They contain aterminator.

More than one of the above isfalse.

Flag this Question

What is NOT a potential problem(s) associated with usingbacteria containing a cloned eukaryotic gene (e.g. a human gene) toproduce a functional protein?

If the eukaryotic genecontains introns the bacteria will not remove them and theresulting amino acid sequence will be different that that made by aeukaryote.

The bacteria may not fold theprotein correctly.

The bacteria may degrade theprotein.

All of the above are potentialproblems.

Flag this Question

Cloning allows for production of proteins in much larger amountsthan occurs in the cells from which the gene is isolated.

True

False

Flag this Question

Question 111 pts

Gene cloning is used to do all of the following except

Make insulin