CHAPTER 5 BACTERIAL TRANSFORMATION & POLYMERASE CHAIN REACTION - Salaya Washington

What is the clinical significance of bacterial transformation in biotechnology

It explains antibiotic resistance spread,enables genetic engineering for insulin production

When did Griffith discover transformation

1928

How did the mouse die in station 1

Because it was injected with s -strain causing phenomena

What did the s-strain contain?

polysaccharide capsule

How was the R-strain different from the S-strain

The R-strain lacks a capsule

What happened in station-3 of Griffiths experiment

Heat killed S strain and the mouse survived

What happened in station 4?

There was a mix of heat killed s-strain and r-strain which killed the mouse

How did the bacteria demonstrate genetic variation?

because of the transformation in R-strain acquired from the dad s-strain DNA

What happens during DNA release and uptake in the transformation process?

Killed s-strain DNA is expressed in recipient bacterium

What happens during DNA integration?

Nucleus replaces on DNA strand with homologous recombination using the complementary strand

What happens during bacterial division in the transformation process?

divides bacterium with inherited capsule synthesis capability, giving it the ability to producing s strain disease from harmless r strain

what is the clinical significance of bacterial conjunction?

drives antibiotic resistance, horizontal gene transfer that accelerates bacterial evolution,antimicrobial strategies

what are the different bacterial mating types?

F+ bacterium ( ( genetic donor) F+( genetic recipient) F- chromosome( recipient ) Fertility factor ( episomal DNA conferring donor ability)

What is the fertility factor?

Genetic transfer during conjugation

What is the conjugation bridge?

The connection between cell through the pilus

How are genes transferred during conjugation?

sex pilus

what is high frequency recombination?

The chromosomal transfer that contains f factor integration into chromosome

What is bacterial transduction ?

The transfer of genetic material between bacteria

What happens during bacteriophage attachment

The attachment of the receptor side

what happens during phage DNA replication

the phage attaches to a suitable host cell and integrating it's DNA into it to reproduce

What happen during packaging and phage release?

Once full the mother cuts DNA and detaches creating a full mature infectious phage

What are the steps of generalized transduction?

Phage infection,Host DNA breakdown,accidental packaging of DNA ,release of particles in new cell causing integration into donor DNA into receptiants genome.

What happens during prophage integration and excision?

site-specific recombination,inserting viral genome into DNA , continuing to replicate

What is hybrid DNa formation?

When 2 complementary strands usually from 2 different organisms or species bind together to form a new strands.

How is DNA transferred to recipient ?

Transformation, conjugation,and transduction

What is the pre-integration state?

host cell invaded and RNA is converted to DNA

What is the post-integration state?

When the Dna is integrated into host and now contains recombinant genes passed to daughter

What is the clinical significance of Bacterial Transduction?

factor transfer in staphylococcus aureus and streptococcus as well as antibiotic resistance.

How did genetic engineering revolutionize medicine

enabled mass production of previously scared therapeutics

What is the donor plasmid

easily manipulated ringlets of DNA that serve as vectors for genetic engineering

What are restriction enzymes

Molecular scissors that cleave DNA at specific reignition sites to allow DNA fragment insertion

What are DNA ligase?

molecular glue that seals DNA strands together

Where do foreign DNA come from?

other bacterial, animal cells, or human cells

What is a chimera

recombinant plasmid created that holds of the different organisms DNA

What does Cacl2 solution do to cells?

during bacterial transformation it opens the cell wall and permits chimera entry into cytoplasm while resealing

How can recombinant proteins be used?

harvested from bacterial cultures and used for medical use

How did PCR revolutionize medicine ?

enabling rapid detections of infectious disease from tiny samples

What are primers

the 5’ and 3’ ends which are binding sites

What are DNTPs

the building blocks for new DNA synthesis

What is taq DNA polymerase

synthesizes new DNA strands with the use of Thermus aquatics that survives heating up to 95c

WHat are the three steps of PCR

intitionilization, annealing, elongation

What temp does denaturation occur at

95c

What temp does annealing happen

55c

what happens during the denaturation phase?

breaks hydrogen bonds between complementary strands

what happens during annealing phase

primers bond to single stranded DNA

what temp does elongation happen at

72c

what occurs during elongation stage?

dna template continues to add nucleotides

What does PCR multiply

2^n

HOw many cycles of PCR are typical

25-40 cycles