Gel 1: single digest using EcoR1
1 2 3
Fig.1: Gel 1 shows electrophoresis of Bioline Hyperladder 1(lane 1),
EcoR1 digested plasmid prep (lane 2) and uncut plasmid prep sample (lane
3) in a 0.8% agarose gel. DNA bands are visible due to the fluorescence
of intercalated ethidium bromide. Open circular (OC), linear (L) and
Super-coiled (SC) forms of plasmid DNA in lane 3, are labeled
accordingly.
PAGE
PAGE 1
OC
SC
M E U
Biology Homework Solutions
#159304
Agarose gel electrophoresis - why does my bp not add up?
Will be as brief as I can! - any help would be appreciated.
used 3 lanes on my gel and ran in each:
lane 1: hyperladder (linear fragments)
lane 2: EcoR1 digested recombinant pUC18 (size of insert unknown)
lane 3: undigested recombinant pUC18 plasmid
Results obtained from gel and standard curve:
lane 2: 2 bands apparent - determined as 3890 and 257 bp.
lane 3: 3 bands apparent - linear band determined as 5011bp
A pUC18 plasmid (without insert) has 2687bp so from the results obtained from lane 3 this would suggest the insert is 2324bp. My results from lane 2 don't confirm this at all though!!
The largest fragment band of digested pUC18 (lane 2) migrated further than the linear undigested pUC18 in lane 3 and almost as far as the band which represents the undigested plasmid in its supercoiled form. I don't understand why????
I realise that this method of determining the size in bp of DNA is not very acurate but this doesn't explain why the digested fragment migrated further than the undigested pUC18.
If you can help at all I'd be really grateful - many thanks
What is this?
By OTA - Overall OTA Rating
Adam Ritchie, PhD - 4.9/5
Purchase Cost Now
$2.19 CAD (was ~$11.97)
Included in Download
- Plain text response
Why you can trust BrainMass.com
- Your Information is Secure
- Best Online Academic Help Service
- Students find real academic Success
- The definitions of merozygote, recombinant frequency, recessive phenotype and sex chromosome. - Define the following terms: MEROZYGOTE RECOMBINANT FREQUENCY (RF) RECESSIVE PHENOTYPE SEX CHROMOSOME
- Drosophila linkage relationship - An experiment was done to determine the linkage relationship of three genes (a,b,c) in drosophila melanogaster. Homozygous females phenotypically a,c were crossed with homozygous males phenotypical ...
- A definition of genetic map units. - Define and describe genetic map units.
- Methods of forensic DNA profile analysis - More methods of VNTR analysis 1. Which of the following is NOT a part of the methods used in single locus probe analysis of VNTR regions of human DNA? Please explain the right answer. A. DNA e ...
- A reaction to recombinant DNA technologies is included. - a. Do you think that using recombinant DNA technologies to change the genetic composition of a human egg cell is ever justified? b. If so, what restrictions should be placed on such a use? c. Wh ...
