| CPU_Nanjing - iGEM 2022

Overview

It is our honor this year to have the opportunity to contribute to future iGEM teams striving for the improvement of synthetic biology and extending the boundary of natural science. Our contribution mainly consists of the following three aspects:

(1) we built new Parts and improved several existing Parts;

(2) we developed two simple methods that may facilitate relevant researches performed by future teams;

(3) we manufactured three kinds of products that may be helpful to the projects of future iGEM teams.

Parts

This year, we built four new Parts and made significant improvements on three existing Parts. For detailed information of these Parts, please refer to the links (presented as Part Number) listed in the following table.

Number	Name	Type	Description
BBa_K4257000	PPK-M	Basic	New Part: polyphosphate kinase mutant. The existing part we improved: BBa_K1807009
BBa_K4257033	KPD+CFPPK	Composite	New Part: phosphite dehydrogenase coupled with polyphosphate kinase. The existing parts we improved: BBa_K2325001 and BBa_K3022002
BBa_K4257022	RPD+PPK-M	Composite	New Part: phosphite dehydrogenase coupled with polyphosphate kinase mutant.
BBa_K4257011	RPD	Basic	New Part: phosphite dehydrogenase from Ralstonia sp. strain 4506.

Methods

Quick polyP staining -- Polyphosphate (polyP) plays essential roles in various biological processes, where tracking intracellular fluctuation of this biopolymer is an indispensable part of work. PolyP is a polyanionic biopolymer and generally stored in cells in the form of polyP granules. To facilitate the intuitively observation of this intracellular biopolymer, we developed a quick polyP staining method that only involves four simple steps.

The feasibility and sensitivity of this method has been verified by two independent labs with two different bacterial strains. Therefore, we proposed that this method can be adopted by future iGEM teams if polyP is involved in their project.

Algae lysate preparation -- In the process of developing carbon source for E. coli, we found that algae could be the potential source for a type of natural medium. However, due to the antagonistic action between bacteria and algae, a pretreatment must be performed to convert live algae to assimilable organic matters. After several rounds of tests, it turns out that boiling is the simplest way. The algae lysate prepared in this method can be directly subjected to bacteria cultivation.

Given that this method is so simple and algae may be involved in the projects of future iGEM teams, we recommend that they use this method to treat algae whenever algae lysate is needed.

Products

In addition to the final product phosphate, we have developed another two kinds of products - biosynthesized polyP of long mixed chain-length and algae lysate. Among them, polyP can serve as a valuable reagent for scientific research and algae lysate can be a new type of natural medium. Possible applications on these products including the phosphate we manufactured have been described in detail in the corresponding part of our project. All the products can be served upon request. We hope that they could be helpful to the projects of future iGEM teams.