Part:BBa_K2533050

mleS-lldp-ldhA

malate dehydrogenase & L-lactate permease & D-lactate dehydrogenase

Usage and biology

dld refers to FAD-dependent D-lactate dehydrogenase which could catalyze D-lactate’s transformation into pyruvate. With the overexpression of dld, Shewanella could utilize D-lactate more efficiently, which brings more electricity being produced.

Characterization

This is one section for lactate utilization part.

File:T--HUST-China--2018-tonglu-mleS-lldP-ldhA

Figure1:mleS-lldP-ldhA

DNA Gel Electrophoretic

To make sure that we get the target gene, we did the DNA gel electrophoretic to separate different gene. And here is the result. [[File:T--HUST-China--2018-jiaotu-mleS-lldP-ldhA.png|400px|thumb|center|Figure2:Verification of successful transformation of pSB1C3-mleS-lldP-ldhA] Our target genes are 4339bp, and as the marker is DS5000, we could be sure that the bright bands in this picture are our target genes.

Electrogenesis

By comparing the ability of producing electricity, we might find out whether dld could effectively help Shewanella to produce more electricity.

Figure3:shows that our modification is effective. Every gene circuits can help strains produce lactate, and mleS-lldP-ldhA is the most efficient one. Therefore, our construction of gene circuits achieve the goal to help strains produce lactate.

It could be demonstrated that targeted genes could be expressed in the engineered cells. More NADH has been produced by engineered bacteria, which helps to produce more electricty.