Difference between revisions of "Part:BBa K1796001"

Revision as of 19:32, 18 September 2015

promoter of Paenibacillus sp. WLY78 nif gene cluster

The promoter of Paenibacillus sp. WLY78 nif gene cluster, We named it Pnif. Pnif is a σ70-dependent promoter located upstream of nifB. Pnif is in control of all the gene clusters of nitrogen fixation genome.

Usage and Biology

Sequence and Features

Confirmation of nif promoter

We standardized the nif promoter of Paenibacillus sp. WLY78, and linked it to the upstream of 3 reporter genes (RFP reporter: BBa_K1357010, YFP reporter: BBa_E0430;amilCP reporter: BBa_K1357009) to confirm the reliability of this promoter. The results are shown in Figure 2.

 A                                                                                        B

  C

Confirmation of nif promoter of Paenibacillus sp. WLY78. (A) Pnif+RFP reporter; (B) Pnif+YFP reporter;(C)Pnif+amilCP reporter.

The results confirmed the reliability of Pnif. The initiation of Pnif does not require inducement. Thus it is a effective constitutive promoter.

Functional Parameters

Flow cytometry test

We also tested Pnif expression with flow cytometry. A GFP biobrick part BBa_E0240 was linked downstream of this promoter, then we tested both Pnif sample and a blank control sample simultaneously. The GFP expression by Pnif was clearly shown in the result

All the data of blank control was shown in the left, and the data of CFP expression was shown in the right.

Relative promoter strength estimates

SCU_China's MEASUREMENT

Comparison of the expression efficiency of Pnif and Pd. Pd: Promoter BBa_J23100; Pnif: nif promoter.