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22 mayo ++ Kissing ++ Kiss on the cheek - Just friends Kiss on the hand - 'i adore you' Kiss on the neck - 'we belong together' Kiss on the shoulder - 'i want you' Kiss on the lips - 'i love/want you' Holding hands - 'we can learn to love each other' Slap on the butt - 'thats mine' Laughing while kissing - 'i am completely comfortable with you'
... Sorry.. was on an email Micah sent me... couldnt help it. 21 mayo Bacteria, Viruses and other yummy sweetsMost of us have conflicts within bacteria or viruses sometime in their lives (if you dont.. contact me!!! I want to study you!!). Even though we are always in contact with our little microbial partners, many people who dont undergo the torture of a science degree (with a slight focus in microbiology) dont actually know much about them.
So i am here to slight enlighten you.
*Throughout my spiel, please remember the central dogma of genetics:
DNA --(transcription)--> RNA --(translation)--> Protein
Also, prokaryotic cells (which include bacteria and viruses, not humans, we are eukaryotes) do not undergo post translational modification, such as splicing of introns and the joining of extrons such as what happens in eukaryotic cells. However.. viruses are a little tricky and do undergo some modifications... but more on this later!
First off we shall explore the arch enemies of bacteria and viruses- antibiotics.
When the word antibiotics comes to mind, most people think of penicillin and its famous discoverer Fleming.
The first substance to have selective toxicity on bacteria (i.e. would usually specifically target bacteria, but in early cases could have also affected other things) was Salvarsan which was developed in the early 1900's by Ehrlich as a effective treatment against syphillius (a STD which usually produced fatalities) however it had rather toxic side effects.
Lets now focus more on the superstar of antibiotics - penicillian. Discovered by fleming in 1929, an often misconception people have is that Fleming actually had something to do with it becoming a widespread antibiotic that helped millions of people. When in fact, (and i didnt know this either until the lecture), Fleming accidently left a petri dish of bacteria on a bench which were contamined by a mould, overnight, and when he came back in the morning, he found that the contamination had inhibited and killed the growth of the bacteria on his plates. He named the mould 'penicillian' after the genus name of the mould (penicillian penicillan). This is where Fleming stopped.
It was little known Florey who actually developed a process to manufacture large scale production of penicillian from the late 1930's to early 1940s. He was also the person who demonstrated that it was effective in treating infectious disease.
Fleming, Florey and (a partner) Chain won the Nobel Prize in 1945.
Now as many people know (or should know) soon after penicillian was introduced into the world, there were cases of people being resistant to the drug. Doctors and scientists were stumped.
What they didnt connect was that penicilian was a natural substance, a mould which grew in the ground. Why wouldnt diseases which competed with penicillian for nutrients have created their own resistance to it?
And this is just what happened - A few years after an antibiotic was released, the disease had already evolved to be resistant to it.
Cells are smart... they evolved to create enzymes which could chop up antibiotics to inactivate them or some pumped the antibiotic out of the cell so it couldnt build up in large concentrations which would kill the cell. Or perhaps they can degrade antibiotics?
There is evidence viruses and bacteria not only rapidly evolve to new antibiotics but have already possibly (even decades before) have evolved for these antibiotics..
The main problem with antibiotics is the reliance of natrual molecules as antibiotics because the diseases have probably already had interacts with them.
Bacteria are also very sneaky microbes. They have these extra circular molecules called plasmids, which can hold self replicating genetic information (apart from the cellular chromosomes of the bacteria). Now these plasmids are key to antibiotic resistance because this is the site where antibiotic resistant genes are most likely to occur. As a bonus, the bacteria can directly uptake these resistance genes (as DNA ofcourse) from the environment, however this can only happen between the same species of bacteria.
Bacteria can also 'transduct' or transfer a copy of its DNA to another bacteria of the same species.. this is called horizontal gene transfer.
However the most kinky and fascinating mechanism is conjugation, or bacterial sex as it is understood in the microbiology world.
Conjugation is where the plasmid itself mediates the transfer (controlled and initiated by the tra genes on the plasmid) of a copy of its own plasmid to another bacterial cell.. regardless of what type, genus, species it is.
It does this by extending a thin 'feeler' or sex pilius to a nearby bacterial cell and pulls it in closer to it, then extending the pillius to a bridge which the plasmid genetic information can travel down and assemble back into its plasmid circular structure at the recipient cell. This way, a possibly completely foriegn cell can trade genetic information ... and this information can be on anything... commonly antibiotic resistance but also mechanisms for combating possible obstacles within the environment such as a nutrient shortage or temperature.
So.. we have bacteria who already have dealed with our antibiotics, and have mechanisms which can very quickly adapt or trade genes for adopting resistance to bacteria. We are screwed.
Bacteria have also created integrons which combine a single promoter for a whole bunch of genes on a plasmid so that it takes less time and energy to create or move (to another plasmid) antibiotic resistance genes.
IN ADDITION (yes theres more) viruses and bacteria have figured out that there are features about them (such as surface expressed virulence factors... think tentacles and such) which induce an immune response, so they can randomly switch them off to not induce a response and then randomly switch them back on again.. cool huh? Its called phase variation.
There are lots of other things.. but i am really tired now.. and hungry.. so i might continue later, i might not, either way i hope you have gained some sort of insight into the microscopic world living in, on and around us.
P.S. Panic! At the Disco is an awesome band!! Check out their song - 'lying is the most fun a girl can have with her clothes on!'
Ciao!
--Ania
12 mayo blahnessAnother entry, another unfortunate day :P Today shouldnt be too bad, i've nearly finished uni (just one genetics lecture left, and i like the lecturer..) and then i have several hrs of work (i can finally eat!! i am starving!!) *Listening to within temptation from my *new* USB Drive.. 1gb.. oh yeah.. * Hmm.. I felt rather strange last night, it was the first time in a few years and i felt particularly bad .. (the people who have known me for a few years may or may not know what i am talking about). I would like to publically (as publically as I can) apologise to Mitch.. for freaking him out last night.. sorry.. i didnt expect you to call me.. and i am pretty sure i sounded alot worse then i was. I guess everything just got to me and that was one factor that was continously trying to bite me. (alot of things try to bite me.. i have 2 large bites from something.. thinking its a sand fly.. but why cant they just leave me alone???) Um, so yes sorry.. i will explain to you if you really want to know. but its just emotional baggage shit that doesnt usually matter... Only once in a while during my crazy periods :P Anyway.. i should go coz i have nothing else to say!! * Ciao * --Ania P.S I am pretty sure 'ciao' can be used as hello and goodbye, my friend matt seems to disagree with me.. ?? Any input? 07 mayo Laptop Update 2.0Just a quick note to say that i dont have my laptop -- its off having a good ol time in sydney getting fixed up, so i wont be online as much.. or blog as much until my laptop gets back!!
SO yes :P
--Ania 04 mayo Good Morning WorldGood Morning,
Its 8:19am, i am sitting in iLC 2 (which is pretty cold compared to iLC 4), and i am contemplating.
What are you contemplating you may ask? --Well i am not sure yet, i suppose i am contemplating what to contemplate.
As you may have noticed my brain is currently still asleep, even though i have dosed it with strong caffeine to jump start it, however i doubt that will last until my 10am physical chemistry lecture, and as usual my head will want to draw demented animals all over my lecture notes.
I have noticed that my language has quite rapidly degraded into a more common and less complex vocabulary, so i am going to try and force it back up to the level at which it rested when i graduated high school -- i cant let all those years being prepped by ms. Kav go to waste!! It was so much fun!
Does anyone know how to calculate the temperature two solids are at equilibrium when given the phase transition and freezing point at a certain pressure??
Or the value of change of entropy for a reaction when given heat of vaporation, boiling point at a certain temperature and pressure?
Or perhaps calculating an equilibrium constant a reaction of NO at 1000K when given the standard free energy ?
Hmm...
Oh! My laptop is probably getting sent over to Dell on monday so from then on i will have restricted access to computers -- ie. email, messenger etc, so please bear with me.. i will be online at uni and stuff to do assessments but it wont be as much as i usually am.
Gracie!!
--Ania |
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