Part:BBa_K519020

Plac-Lysis device without antiholin

P(J23109)-RBS(B0034)-LacI(I732100)-Term(B0015)-Plac(R0010)-Holin(K112805)-Endolysin(K112806)-Term(B0015)

This part is consisted of constitutively expressed lacI, and IPTG inducible lysis genes holin and endolysin derived from T4 bacteriophage. Antiholin is deleted from BBa_K317040 a lysis device we construted in iGEM2010. Holin and endolysin are lytic protein that makes the cell wall lyse. When holin makes a multimer on the cell inner membrane, endolysin that accumulates in the cytoplasm can go through the holin to enter the periplasm of the cell wall. Endolysin which is a lytic enzyme then makes glycosylase reaction to breakdown the peptidoglycan layer, leading to cell lysis.

We performed an experiment to see how much the presence of antiholin can affect the expression of lysis in cells. We cultured E. coli transformed with our construction from last year, a lysis device with antiholin, and an E. coli transformed with our lysis device this year, a system without antiholin. Comparing the growth curve of the two and the wild type E. coli at OD660 without IPTG induction, we observed that E. coli with lysis genes did not reach OD660 as high as the wild type indicating that there was a leakage in expression even without IPTG. Furthermore, comparing the the system with and without antiholin, OD660 of an E. coli that does not have antiholin reached an OD660 lower than that of E. coli expressing antiholin.


Sequence and Features