Class Notes (835,006)
Canada (508,865)
UOIT (1,700)
Biology (294)
BIOL 2050U (48)
Lecture

COMPLEMENT

2 Pages
92 Views
Unlock Document

School
Department
Biology
Course
BIOL 2050U
Professor
Peter Cheung
Semester
Fall

Description
COMPLEMENT req. for phagocytosis antibody secretion cytolysis Complement cascade – 2 parts (enzymatic and lytic/pore forming) 3 PATHWAYS TO ACTIVATE C3: CLASSICAL: C1 binds ANTIBODY via Q domain (C1Q) must bind MULTIPLE antibodies FC’s for protease activity (IgM, 2 IgG’s) C1S cleaves C4 into A and B  C4B attaches to bacterial surface attracts C2 C1S cleaves C2 into A and B fragments  C4B + C2A = CLASSICAL C3 CONVERTASE (C3-directed protease) MBL (mannose-binding lectin) same process except MBL substitutes C1 complex binds mannose via its lectin heads then cleaves C4 and C2 to make Classical C3 Convertase **no antibody recognition necessary; bacteria is directly recognized** ALTERNATIVE simplest, most primitive way C3 binds bacterial surface spontaneously then binds FACTOR B which is cleaved by FACTOR D into a and b Bb stays behind PROPERDIN stabilizes C3Bb  ALTERNATIVE C3 CONVERTASE **both convertases have same function: CLEAVE C3 into C3b** both also have sim. structure (C4b:C3b::C2a:Bb) AMPLIFICATION – presence of one C3b leads to activation of 250+ others some bind bacteria covalently (thioester); most are hydrolyzed by water PHAGOCYTO
More Less

Related notes for BIOL 2050U

Log In


OR

Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


OR

By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.


Submit