Hey All Removed plugs from SpeI enzyme buffer…

Hey All,

Removed plugs from SpeI enzyme, buffer and BSA, and washed in 1x wash buffer for 30mins. We removed this, then incubated them in 0.5x TAE buffer for an hour, while we prepared a 1.4% agarose gel. We then loaded 1/2 of each plug strain into individual wells, as well as the low range PFG marker, sealed with agarose and ran at 6V/cm, for 15 hours, with a 1-12 sec switch interval, and modified buffer flow.

Tomorrow, we will remove the gel, stain it and view it. We will also be filming our last videoblog! 🙁 as it will be the last day of our project – 10 weeks has gone by sooo fast! We may also be running another gel, depending on the results of the first. See you all then 🙂

Hello Today we removed the plugs from proteinase…

Hello,

Today we removed the plugs from proteinase K, and washed them in 1 x wash buffer 4 times, for an hour each. We then incubated them in 0.1 x wash buffer for an hour, then in 1 x SpeI buffer to saturate for an hour. We then removed and added fresh SpeI buffer, SpeI enzyme and BSA and incubated overnight at 37C. We also made up 500ml of 0.5x TAE buffer and autoclaved it for tomorrow.

Unfortunately, we lost a few plugs along the way, due to instability. Tomorrow we will be incubating the plugs in 1 x wash buffer, then 0.5x TAE, before running the new plugs.

Hey All Today i came in and filmed…

Hey All,

Today i came in and filmed my latest videoblog. I then removed the plugs from speI, buffer and BSA, and added 0.1x wash buffer for 30mins. While this was incubating, i autoclaved 1L of 0.5x TAE buffer, which i then used to incubate the plugs for an hour. I then prepared a 1.4% gel, with modified comb to create a large well. Once this had solidified i added one plug of the low range PFG marker, one whole plug of restriction enzyme treated plug in the large well, and finally one 1/3 of a restriction enzyme treated plug in one well. I then sealed the plugs, and ran the gel at 6v/cm for 15hrs, with 1-12sec switch interval ramping.

Mike will be in tomorrow to removed the gel, stain it and view. He will then save an image for me to observe with him on Monday 🙂 See you all then!

Hey Everyone Today was a loooong day Came…

Hey Everyone,

Today was a loooong day! Came in at 9am, and as the plugs were still fairly cloudy, Mike suggested we leave them abit longer to allow further lysis, and therefore make the plugs clearer. We made up a fresh solution of lysozyme, proteinase K and mutanolysin, and left the plugs to incubate further until 12pm.

I then began washing the plugs in 1x wash buffer, 1hr each four times. Once finished i washed the plugs in 0.1x wash buffer for an hour twice. I then removed the wash buffer and added speI buffer to allow the plugs to incubate for an hour. After this i added fresh buffer, SpeI enzyme and BSA. The plugs will incubate overnight at 37C.

I made appropriate modifications in amount of lysozyme, mutanolysin, SpeI buffer and enzyme etc. In order to compensate for an increase in DNA conc.

Tomorrow i will be filming my new videoblog, then incubating the plugs in 1x wash buffer, and in 0.5x TAE buffer, before setting up and running a new gel with our new modifications, that looked like they worked very well on weds.

Hey All Didn’t come in till late today…

Hey All!

Didn’t come in till late today, to allow Propionbacterium acnes 6919 strain sample to grow, however the sample hadn’t grown enough, so we have left it to grow till tomorrow.

Meanwhile, i removed the plugs from speI, washed them in 1x wash buffer for 30 mins, then incubated them in TAE 0.5x until i had made and set a new gel. I used the modified comb as before to create an extra large well, so i could use 2 plugs in 1 well, as the plugs are from an old batch and therefore still contain minimal DNA.

I then ran the PFGE for 15hrs, at 6V/cm, with 1-12sec switch intervals. Mike also suggested using an increased amount of buffer in a large container below, and pumping buffer through the PFGE to replace buffer as it left the PFGE back into the container. This will hopefully keep all the buffer in the container as cold as possible, reducing smearing and making bands clearer.

Tomorrow, if the cells have grown enough, i can start to make new plugs, with our modifications.

Hello Everyone First day back in the lab…

Hello Everyone!

First day back in the lab! Me and Mike had a quick chat about what i wanted to do next and made a plan for this week, and possible plans for my final few weeks in the lab – it’s gone soo fast!
Mike re cultured the Propionbacterium acnes 6919 strain samples to allow them all of today and tomorrow morning to grow. Meanwhile, i treated my 3 remaining plugs with restriction enzyme – SpeI, which needs to incubate overnight. I also prepared and autoclaved 3L of 0.5X TAE buffer ready for running a gel with the restriction enzyme treated plugs and the low range PFG marker, using the settings we decided on last time i was in the lab – 6V/cm, 15hrs, 1-12sec Switch Intervals and a 1.4% gel.

Tomorrow will be a late start, to give Propionbacterium acnes 6919 strain samples as much time as possible to grow, before i begin making new plugs with our decided on modifications and setting up and running a new gel with the restriction enzyme treated plugs and new settings. Hopefully we will get some clearer and just as positive results! 🙂

Evening Today we washed our plugs as before…

Evening,

Today we washed our plugs, as before in 1X wash buffer 4 times for an hour each. We then separated our 5 plugs into separate eppendorfs, and put 3 in storage in fresh 1X wash buffer. To the 2 remaining plugs we added 0.1X wash buffer for an hour.

To one we removed the wash buffer and added 1ml of Spe1 buffer to saturate for an hour. We then added fresh Spe1 buffer, Spe1 enzyme and BSA, and incubated overnight at 37C.

We set up a new gel in order to run the unrestriction treated plug, to ensure that the DNA within the samples are viable for use. If we see one large band just below the wells, that is as clear or clearer as our best previous gel run, then we will run a gel with the same settings, but with restriction enzyme treated plugs.

We made up 3L of TAE 0.5X and a 1% gel. We removed the wash buffer from the other plug and added 1ml of TAE 0.5X buffer to saturate it. Once the gel had set, we cut and placed 2 non restriction enzyme treated plug sections and 2 sections of the new low range PFG marker into the wells and sealed with agarose. We ran this gel at the low range PFG marker settings: 1% agarose gel, 15 hours, 1-12 second switch interval ramping and 6V/cm.

I also filmed with Sophia and Barney, regarding their experiences in the lab so far! 🙂

We will remove this gel tomorrow, stain it and view it. This will help us to decide whether to run the restriction enzyme plug, with the same low range PFG marker settings.

See you all tomorrow!

Hey Everyone Came into the lab this morning…

Hey Everyone,

Came into the lab this morning to start to set up our next gel. I made up 3 L of TAE 0.5X, incubated 1 Propionibacterium acnes 6919 strain restriction enzyme plug and 1 non restriction enzyme plug in 1X wash buffer and then in 0.5X TAE buffer. I then made up a 1% agarose gel and left it to set. I put the gel and plugs into the fridge and left them until 5pm.

When i came in at 5pm, i cut and loaded 2 samples of Propionibacterium acnes 6919 strain restriction enzyme plug, 1 sample of non restriction enzyme plug and 1 NEB yeast ladder. I sealed the plugs and then ran the gel according to the info recommended on the low range PFG marker ladder, for 15hrs, at 6 V/cm, with a ramped switch interval from 1-12 seconds. I added a second block as the gel is only running for 15hrs, and will finish at 8.30am tomorrow morning, of 0.6V/cm for 2hrs with a 5 second switch interval.

We will hopefully have the new ladder tomorrow, so we can modify our new gel according to the results we get when the run finishes tomorrow and use the new ladder!

See you all tomorrow 🙂

Hello Everyone Came into the lab today removed…

Hello Everyone!

Came into the lab today, removed, stained and viewed our latest gel. We observed a clear similar band under all the samples not treated with restriction enzyme, and slightly blurry similar band under all samples treated with restriction enzyme. Although the position of the bands are correct, the blurriness suggests that separation is still not occurring properly. There also appears to be a problem with the sealing agarose, resulting in very dark wells as DNA cannot properly leave the wells. This was actually my fault, as when making up the sealing agarose for the wells, i had been mixing the same 1g of agarose used in making the actual gel, in the smaller amount of buffer (50ml) used when making the sealing agarose, instead of halving the agarose to 0.5g. Therefore we were attempting to seal the wells with 2% agarose, which explains the difficulty we had in pipetting it (the formation of bubbles), the dark wells and smearing of samples through the gel.

We decided on the following modifications:

  • Increase the agarose gel % from 1% to 1.3/1.4%, in order to help increase the separation of fragments.
  • Use the correct agarose gel % to seal the plugs into the wells, hopefully decreasing the dark wells and smearing, and increasing the movement of DNA through the gel clearly.

We then ran a standard 0.8% agarose gel, with 0.5X TAE buffer, for 2 hours at 100V. We ran 3 large samples of restriction enzyme treated plugs, 1 Kb ladder and lambda Hind III ladder. We sealed the plugs in with 0.8% agarose (0.4g agarose and 50ml 0.5X TAE buffer).

The results of this confirmed our modifications, and tomorrow we will be running a new PFGE gel for 24 hours, at 4 V/cm with a 20 second switch interval, applying our modifications.

See you all tomorrow 🙂

Hi all Interesting day started the day by…

Hi all,
Interesting day, started the day by making 3000ml of TAE buffer. Next i ran a PCR test with a sample of my hair. When we looked at the gel under the UV some showed two bands and some showed just one band, either i’m a boy or luke is a girl. Think we may need to redo the test and look up which banding type (1 or 2) shows a male or female. Researched a few of the bacterial cultures on my bench, some are same species where an indole test is the only way to differentiate them.

Hey All Today we came in removed stained…

Hey All,

Today we came in removed, stained and viewed our gel. The samples not treated with restriction enzyme showed a similar band, just underneath the wells. This was expected as the samples had not been treated and therefore lysed by the restriction enzymes, so separation according to size did not occur, producing only one/two bands. The samples treated with restriction enzyme showed some separation, but not enough, possibly due to not enough digestion. For both sample types it appeared that the largest plug size used worked the best. Mike also noted that this may be due to a lack of cell density within the plugs. The agarose gel also appeared very messy, and needed to be cleaned up. We destained the gel in TAE buffer, viewed it again and decided on the following modifications for our next PFGE run:

  • Run for 20 hours with a 20 second switch interval. The switch interval was decreased in order to produce better/clearer separation.
  • 3 large samples for each plug treated with restriction enzyme and those without, as the larger samples seemed to work the best.
  • We also deep cleaned our glass wear and autoclaved the buffer used within the sealing agarose, in order to try to clean up our gel as best as possible.
  • Finally, when we produce more plugs, we will try to increase the cell density within the plugs and modify our cell suspension buffer/centrifuge stage.
  • We are keeping the buffer, ladder, sealing in plugs, temperature and voltage the same.

Excited to see if our modifications produce clearer band separation 🙂

Evening Everyone Didn’t come into the lab till…

Evening Everyone!

Didn’t come into the lab till the afternoon today. Once we got in we removed the buffer from the plugs, and incubated them further in 1X wash buffer for 30 mins, at room temperature. While this was incubating myself and Jo made up 3L of 0.5X TAE buffer, melted agarose and then poured a new gel. The buffer was then removed and replaced with some of the 0.5X TAE buffer, that will be used to run the gel, to allow equilibration. We then cut and loaded 3 samples of fully treated Propionibacterium acnes DNA, 3 samples of Propionibacterium acnes DNA not treated with the restriction enzyme (SpeI) and 1 sample of lambda Hind III as a reference ladder.

Finally we sealed the plugs in with agarose and set the PFGE to run for: 12.7 hours at 6.0 V/cm with a ramping of 1-8 seconds, then 7 hours at 6.0 V/cm with a ramping of 0.1-2 seconds. We haven’t tried ramping before, but we decided to try this set up, as it is the method used in one of the journals we have been working from. Ramping is where one switch interval is used at the beginning of a time run, and another is used at the end, therefore over the time period the ramping slowly changes.

Tomorrow we will be filming our next videoblog, removing, staining and viewing our gel. As mike won’t be in, we will be discussing modifications and a plan for next week on Monday.

See you all tomorrow! 🙂

Hello Everyone Myself and Jo got into the…

Hello Everyone!

Myself and Jo got into the lab early this morning, in order to set up our next PFGE run with our new modifications. We made up 3L of 0.5X TAE buffer and 150ml of agarose (in order to reduce error), then left the gel to set. While it was setting we made up 50ml of agarose to seal the plugs into the wells. We then cut up 4 samples of NEB yeast, pushed them into the wells and sealed them up with agarose. We then set up the PFGE equipment to run at 6°C, for 15 hours at 6 V/cm with a 70 second switch interval and then for 11 hours at 6 V/cm with a 120 second switch interval.

The run is to finish at 12.15pm tomorrow, so myself and jo will be in the lab from 11am to film our second videoblog section! 🙂

See you all tomorrow morning!

Evening all Myself and Jo spent this morning…

Evening all!

Myself and Jo spent this morning researching the next stages of our project, then we came into the lab for 3pm, in order to take our gel out of the PFGE. We then stained it up and viewed it with Mike. We saw much better separation than before, with the bands reaching all the way to the bottom of the gel, and running off. Both yeast samples, BioRad and NEB, also appeared consistent with each other. The 1Kb ladder was not visible, which was expected. However, the separations slightly shifted to the right, producing wonky bands, that unfortunately weren’t very defined. Mike said this was most likely due to imperfections in the agarose, and we could rectify this by producing 150ml of agarose in order to reduce error. In order to try and stop the yeast sample running off the gel we decided to change our switch interval as well. We also decided that as the NEB yeast has been the most consistent and successful sample, we would stop running the BioRad yeast and 1Kb ladder. We will keep the size of the plugs the same, and well as sealing them with agarose.

Reviewing the NEB yeast information we decided to try running our next gel following the guidelines provided, 1% agarose, 15 hours at 6 V/cm with a 70 second switch interval and then 11 hours at 6 V/cm with a 120 second switch interval. Using 0.5X TAE buffer, 2 samples of NEB yeast and at 6°C as before.

See you all tomorrow morning as we set up our next, and possible last gel before starting on our next stage in the project! 🙂