Difference between revisions of "Part:BBa K2325104"

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The BBa_K2325104 is a construct contains N20 sequence selected from the genome of T7 phage, with a constitutive promoter, which is constructed in the CRISPR/Cas system to make the E.coli be able to confer resistance to T7 phage.
 
The BBa_K2325104 is a construct contains N20 sequence selected from the genome of T7 phage, with a constitutive promoter, which is constructed in the CRISPR/Cas system to make the E.coli be able to confer resistance to T7 phage.
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===Background===
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The 20-bp complementary region (N20) with the requisite PAM (NGG) matching genomic loci of interest was programmed directly into a heterologously expressed CRISPR array, and fused crRNA and tracrRNA as a single synthetic guide RNA (sgRNA) transcript obviated the need for processing the transcribed CRISPR array (pre-crRNA) into individual crRNA components.
  
 
===Gel analysis===
 
===Gel analysis===

Revision as of 09:47, 29 October 2017


N20-sgRNA function device in pTarget

The BBa_K2325104 is a construct contains N20 sequence selected from the genome of T7 phage, with a constitutive promoter, which is constructed in the CRISPR/Cas system to make the E.coli be able to confer resistance to T7 phage.

Background

The 20-bp complementary region (N20) with the requisite PAM (NGG) matching genomic loci of interest was programmed directly into a heterologously expressed CRISPR array, and fused crRNA and tracrRNA as a single synthetic guide RNA (sgRNA) transcript obviated the need for processing the transcribed CRISPR array (pre-crRNA) into individual crRNA components.

Gel analysis

BBa K2325104--1.png

Usage and Biology

The pTarget-N20 processing this device is co-transfected with pCas into E.coli BL21(DE3) strain, resulting in BL21(DE3)(pCas+pTarget-N20).

BBa K2325104--2.png
Figure 1. Growth curve of BL21(DE3) (pCas+pTarget) with and without the T7 phage infection and E.coli BL21(DE3)(negative control) with the T7 phage infection in LB media.

We cultivated both the BL21(DE3) (pCas+pTarget-N20) and negative control BL21(DE3), with T7 phage added in liquid LB medum when the bacteria reached logarithmic growth period. To estimate the resist efficiency of the CRISPR system, we also set a control group when BL21(DE3) (pCas+pTarget-N20) was cultivated without phage infection during the period.The results indicated the growth of BL21(DE3) (pCas+pTarget-N20) did not be affected by T7 phage, which convinced that the recombinant strain functioned quite well to resist the phage in LB, and the efficiency of resistance reached nearly 100%.

Sequence and Features


Assembly Compatibility:
  • 10
    INCOMPATIBLE WITH RFC[10]
    Unknown
  • 12
    INCOMPATIBLE WITH RFC[12]
    Unknown
  • 21
    INCOMPATIBLE WITH RFC[21]
    Unknown
  • 23
    COMPATIBLE WITH RFC[23]
  • 25
    COMPATIBLE WITH RFC[25]
  • 1000
    INCOMPATIBLE WITH RFC[1000]
    Illegal BsaI.rc site found at 41