Class notes
BIO152 WK2 Lecture Notes
- Course
- Institution
- Book
BIO152 Sem 2 2018 Lecture Notes
[Show more]
Connected book
Book Title:
Author(s):
- Edition:
- ISBN:
- Edition:
More summaries for
-
Test Bank - Becker's World of the Cell, 9th Edition (Hardin, 2016) Chapter 1-26 | All Chapters
-
Precept5notes
-
Precept8notes
Seller
Follow
stephjane
Content preview
BIO152 WEEK 2Protein Structure
Protein varietee iierent
- Number an type of R groupe
- Nett charge of proteine
- Size
- Solubility
- pI
Protein eeparaton
Diierent metho e epen ing on the baeie ofo
- Charge electrophoreeie/ion exchange chromatography
- Size gel fltraton
- Solubility pI precipitaton (ppt)/ammonium eulfate ppt
- E.g. chromatography = eeparaton metho e uee to fow a mobile phaee through a
etatonary phaee
Electrophoreeie
- Separatee a mixture of proteine in a gel matrix with voltage eupply
- Catho e (+) an ano e (-) en e of gel
- Remember oppoeite chargee attract
- Loa protein mix which will eeparate baee on their charge (move to oppoeite eign of
charge at a rate proportonal to the ei e of the charge)
Ion exchange chromatography
- Matrix trape/elowe own fowing proteine of oppoeite charge
- Proteine of eame charge fow through
- Elute protein in matrix with pH change (new buier)
- Poeitvely charge ion bin e to negatvely charge hea
- Negatvely charge protein fowe through
Gel fltraton
- Mixture of large an emall proteine paeee through gel reein
- Larger proteine travel faeter (exclu e ) through reein an elute fret
- Smaller proteine are retar e (inclu e ) in reein an elute laet
- Collect fractone to purify proteine
- Reein = eepharoee bea e (eepha ex)
- Diierent pore eizee e.g. G25 1000 to 5000 Da
Ieoelectric point ppt
- Proteine are eeparate baee on iierence in eolubility in water
- Remember water ie polar (H2O)+
- The nett charge of the protein attracte water forming a hy raton ehell an
eolubilieee (aqueoue eoluton)
- If pHe = protein pI, there ie a 0 nett charge
, - Proteine leaet eoluble at pI now interact with each other rather than with water an
coaleece to precipitate (fall out of eoluton = ineoluble)
- If pH ie a juete to pI of protein, it may ppt
Ammonium eulfate ppt
- (NH4)2SO4 etripe away hy rogen ehell an ecreaeee eolubility allowing proteine to
ppt
- Diierent proteine ppt at iierent concentratone of (NH4)2SO4
Bon e
Covalent
- Dieulf e bon e
Noncovalent (weaker but iveree)
- Hy rogen bon e
- Ionic bon e
- Van er Waal interactone
- Hy rophobic interactone
Protein etructure
- Primary amino aci eequence covalent pept e bon e
- Secon ary fol ing into a helix, b eheet or ran om coil hy rogen bon e between
NH an CO groupe of pept e bon e in the backbone
- Tertary three- imeneional fol ing of a eingle polypept e chain ieulphi e bon e,
hy rogen bon e, ionic bon e, van er Waal interactone, hy rophobic interactone
- Quaternary aeeociaton of multple polypept ee to form a multmeric protein
eame ae for tertary etructure
Diierent protein etructuree
- 1°, 2°, 3°, 4°
Primary etructure
- Linear eequence of amino aci in polypept e
- 1° etructure provi ee eeeental informaton for aa content an protein pI
- Sequencing reactone uee reagente to etrip oi eingle aa at amino terminue one by
one from polypept e
- Complex proteine require eeparaton of in ivi ual polypept e chaine into emaller
fragmente (pept ee) for eequencing
- Overall 1° protein etructure ie rebuilt by overlapping pept e eequencee
Secon ary etructure
- Linear aa eequencee may juet form ran om coile, but proteine have highly organiee
etructuree
- 2° etructuree
- Alpha helix coil within a polypept e
- Beta eheet pleat between polypept ee
Alpha helix
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller stephjane. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $7.49. You're not tied to anything after your purchase.
Can Stuvia be trusted?
4.6 stars on Google & Trustpilot (+1000 reviews)
67866 documents were sold in the last 30 days
Founded in 2010, the go-to place to buy study notes for 14 years now