Friday 17 June 2011

Daily challenges in the lab

Ah, such is the life of a scientist, where nothing, nothing is straightforward!  Science never sleeps; it is like a never-ending unfolding story, with as many twists and turns as you like and then some.  Recently, yours truly has been going through a rough patch in the lab of late: a ligation experiment that would allow for some wonderful and intriguing discoveries isn't working, the mutant yeast strains I have generated are not what they seem.  I am repeating some stages in my experiment that I did three months ago.  In the meantime, other experiments I really want to do to get things moving are on hold while I try to find out what I am actually working with.


What the hell are you?! Answer me, damn mutant!!

 If molecular biology was a video game and there were bosses - gigantic monsterous enemies you must battle to get to the next stage (not your supervisor, although opinions may differ on this point) - then ligation would definetly be one big bad boss!  The idea of cutting up pieces of DNA with restriction enzymes and sticking them together with DNA ligase sounds simple enough, but there is a lot of fine tuning involved.  The ratio of vector DNA versus insert DNA is important, get this wrong and it might not work.  The ATP in the ligase buffer needs to be in good condition as this is needed by the enzyme to function.  The temperature needs to be right, the salt and pH conditions need to be right, your mood needs to be right, the funny dance that you do with the pirouette at the end to ward off bad luck...right! 

Giant, evil-looking ligation boss: 1 million points ; tiny, suffering scientist: none


But for now, something is amiss and I need to find out why so I can move on.  One of the frustrating things about science is time: it takes a good few hours to digest the DNA, half an hour to clean it up, half an hour to prepare it for ligation and then another hour for the actual reaction.  It can be so frustrating to find out after all that time it hasn't worked and you have used up loads of enzyme, tons of DNA and it is late in the day so there is little you can do about it - apart from huff and puff all the way home.

So, good people of the blogosphere, if there are any scientists out there who can impart a little advice on how to make ligations work, please feel free to sprinkle me some crumbs of wisdom.  Otherwise just wish me luck - I sure could do with some!   

Tuesday 7 June 2011

Scientists selling their wares in a time of crisis

Escherichia coli under the microscope (Image by Rocky Mountain Laboratories, NIAID, NIH)

The big news for the best part of a week has been the E. coli outbreak in Northern Germany, and this morning Professor John Oxford, a leading expert in virology and chairman of the Hygiene Council was interviewed by Eamonn Holmes on his views of the outbreak and what advice he could give to the general public to keep themselves safe.


The Professor answered with a brief low-down of where E.coli comes from ( the animal and human gut) how it got from there to the vegetables (animal and sometimes human waste is used to make manure that is used to fertilise crops) and why, in this case, that the E. coli bacteria from the manure has managed to make it into people's mouths (this new mutant strain of E. coli is more "sticky" causing it to stick to the outside of vegetables so that conventional washing is not enough to remove it.  It also has a way of being able to "wriggle" into the vegetable - where no amount of washing has an effect).  All of these points I agree with - the first two points are common knowledge and the E. coli strain (Enterohemorrhagic E.coli ) uses bacterial fimbriae to attach to surfaces, therefore making it sticky.  The "wriggle" bit I am not too sure about as that would suggest the bacteria has a "tail" that would allow for movement.  However, manure is sprayed on to crops and you would imagine that the fertiliser - and the bacteria - is capable of getting into the little crevices and gaps present in the natural shape of the vegetable.

 The shape of the vegetable, the fruit and their leaves makes it harder to remove potential pathogens (Image by User: Geographer)


However, when it came to giving advice on how to keep ourselves safe from getting infected, the Professor seemed to go off subject and talked about personal hygiene, handwashing and how "manners" is important to make sure that others are kept safe from infection by our own actions.  That is all very well and good and I agree one hundred percent - one should wash hands regularly and yes, one should be considerate towards others, like having your hand over your mouth when sneezing or coughing - but how does that relate when it is the foodstuff that is contaminated? How is handwashing and manners going to make the bacteria unstick from your raw vegetables and stop it from entering your stomach?

  If I scrub my hands hard enough, the bacteria from my salad will disappear! (Image by Serenity)

It was the next words that revealed what was behind his statement - I can't remember the exact words but the word "Dettol" was used.  Bear in mind that John Oxford had some involvement in the Dettol Habit survey and that the Hygiene Council is sponsored by Reckitt Benckiser, a multinational corporation that counts Dettol as one of its power brands.  The Professor continued and ended the interview with advice that people should disinfect more.

 The word infomercial comes to mind

It is already bad enough that in cases of disease outbreaks that we, the general public, have little information to go on except that conveyed by the media - information that is usually sensational and serves to promote fear and panick.  Now there are professionals, experts in the field, that are using this hysteria as an opportunity to endorse products and increase their project funding. 

In times of crisis we all look to those with more knowledge and expertise than us to inform and guide us and we hope that their information is in our best interests.  What we don't need is for these people to take advantage of the situation for their own.  What the good Professor should have said is that since the bacteria cannot be easily removed from the raw vegetables or fruits by washing, that they be cooked thoroughly instead before consumption.  This is just common sense and doesn't require a council and doesn't require a study.

It certainly doesn't require product promotion!

Source: Sky news

Also see: Sell it to me!