Difference between revisions of "Part:BBa K1666000"

 
 
(7 intermediate revisions by the same user not shown)
Line 1: Line 1:
 
 
__NOTOC__
 
__NOTOC__
 
<partinfo>BBa_K1666000 short</partinfo>
 
<partinfo>BBa_K1666000 short</partinfo>
  
In a process called quorum sensing, bacteria communicate with one another using secreted chemical signaling molecules termed autoinducers. As the density of the bacterial population increases, so does the concentration of secreted autoinducer molecules. When the concentration of the autoinducer reaches a critical threshold, it diffuses back into the cell and activates or represses certain target genes.
+
Quorum sensing is a process of bacterial cell-to-cell communication involving the production and detection of signaling molecules named autoinducers. And autoinducer-2 (AI-2) serves as a 'universal signal' for interspecies communication. In the LuxS/AI-2 signaling system of ''Salmonella Typhimurium'', AI-2 response involves ATP binding cassette transporter encoded by genes named ''lsr'' (LuxS regulated). And LsrA is ATP-binding protein that provides energy for AI-2 transport.  
An autoinducer called AI-2 is generated by many species of Gram-negative and Gram-positive bacteria. In the LuxS/AI-2 signaling system of Salmonella enterica serovar Typhimurium, AI-2 response involves genes named lsr (LuxS regulated) that encode ATP binding cassette-type transporter. And LsrA is ATP-binding protein of the ABC transporter. In our project, we set this part under a nisA promoter for the final purpose of constructing an integrated AI-2 response pathway in our engineering bacteria.
+
  
 +
===Usage and Biology===
 +
AI-2 is generated by many species of Gram-negative and Gram-positive bacteria. In a group of bacteria exemplified by ''Salmonella'', AI-2 response involves ''lsr'' genes that encode ATP binding cassette-type transporter. And LsrA is part of the ABC transporter complex, being responsible for energy coupling to the transport system.
  
 +
[[File:NEFU_China_2015_AI-2_response_in_Salmonalla.png|550px|thumb|center|'''Fig1. Schematic overview of the AI-2 response pathway in ''Salmonella Typhimurium'''''The precursor of AI-2, 4,5-Dihydroxy-2,3-Pentanedione (DPD) , is a byproduct generated when LuxS converts S-Ribosylhomocysteine (SRH) to Homocysteine (HCY). DPD then undergoes spontaneously cyclization, forming AI-2, and exports to the culture supernatant. After that, extracellular AI-2 bounds to LsrB, following by passing the membrane channel and importing the cytoplasm. LsrK phosphorylates AI-2 afterwards. The ''lsr'' operon is repressed until phosphorylated AI-2 causes LsrR to relieve its repression on the promoter. And this allows further AI-2 import.]]
  
<!-- Add more about the biology of this part here
+
In our project, we set this protein-coding part under the regulation of a nisA promoter which can be activated by food-grade inducer, nisin. We linearized the related expression vectors and stably integrated them into the genome of the hosts. And together with other parts, we will construct a membrane channel for AI-2 generated by pathogens in the engineered bacteria.
===Usage and Biology===
+
 
 +
[[File:NEFU_China_2015_pnisA_and_LsrA.png|450px|thumb|center|'''Fig2. Part of the vector containing ''lsrA'' '''We use nisA promoter to initiate the transcription of ''lsrA'' gene]]
  
 
<!-- -->
 
<!-- -->
<span class='h3bb'>Sequence and Features</span>
+
<span class='h3bb'>Sequence and Features</span>expre
 
<partinfo>BBa_K1666000 SequenceAndFeatures</partinfo>
 
<partinfo>BBa_K1666000 SequenceAndFeatures</partinfo>
  

Latest revision as of 14:49, 6 September 2015

LsrA of LuxS/AI-2 signaling pathway in Salmonalla

Quorum sensing is a process of bacterial cell-to-cell communication involving the production and detection of signaling molecules named autoinducers. And autoinducer-2 (AI-2) serves as a 'universal signal' for interspecies communication. In the LuxS/AI-2 signaling system of Salmonella Typhimurium, AI-2 response involves ATP binding cassette transporter encoded by genes named lsr (LuxS regulated). And LsrA is ATP-binding protein that provides energy for AI-2 transport.

Usage and Biology

AI-2 is generated by many species of Gram-negative and Gram-positive bacteria. In a group of bacteria exemplified by Salmonella, AI-2 response involves lsr genes that encode ATP binding cassette-type transporter. And LsrA is part of the ABC transporter complex, being responsible for energy coupling to the transport system.

Fig1. Schematic overview of the AI-2 response pathway in Salmonella TyphimuriumThe precursor of AI-2, 4,5-Dihydroxy-2,3-Pentanedione (DPD) , is a byproduct generated when LuxS converts S-Ribosylhomocysteine (SRH) to Homocysteine (HCY). DPD then undergoes spontaneously cyclization, forming AI-2, and exports to the culture supernatant. After that, extracellular AI-2 bounds to LsrB, following by passing the membrane channel and importing the cytoplasm. LsrK phosphorylates AI-2 afterwards. The lsr operon is repressed until phosphorylated AI-2 causes LsrR to relieve its repression on the promoter. And this allows further AI-2 import.

In our project, we set this protein-coding part under the regulation of a nisA promoter which can be activated by food-grade inducer, nisin. We linearized the related expression vectors and stably integrated them into the genome of the hosts. And together with other parts, we will construct a membrane channel for AI-2 generated by pathogens in the engineered bacteria.

Fig2. Part of the vector containing lsrA We use nisA promoter to initiate the transcription of lsrA gene

Sequence and Featuresexpre


Assembly Compatibility:
  • 10
    COMPATIBLE WITH RFC[10]
  • 12
    COMPATIBLE WITH RFC[12]
  • 21
    COMPATIBLE WITH RFC[21]
  • 23
    COMPATIBLE WITH RFC[23]
  • 25
    INCOMPATIBLE WITH RFC[25]
    Illegal AgeI site found at 939
  • 1000
    COMPATIBLE WITH RFC[1000]