Imperial College London

ProfessorPeterNixon

Faculty of Natural SciencesDepartment of Life Sciences

Professor of Biochemistry
 
 
 
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Contact

 

+44 (0)20 7594 5269p.nixon

 
 
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Location

 

705Sir Ernst Chain BuildingSouth Kensington Campus

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Summary

 

Publications

Citation

BibTex format

@article{Zhang:2019:10.1016/j.algal.2019.101702,
author = {Zhang, L and Selão, TT and Nixon, PJ and Norling, B},
doi = {10.1016/j.algal.2019.101702},
journal = {Algal Research},
title = {Photosynthetic conversion of CO2 to hyaluronic acid by engineered strains of the cyanobacterium Synechococcus sp. PCC 7002},
url = {http://dx.doi.org/10.1016/j.algal.2019.101702},
volume = {44},
year = {2019}
}

RIS format (EndNote, RefMan)

TY  - JOUR
AB - Hyaluronic acid (HA), consisting of alternating N-acetylglucosamine and glucuronic acid units, is a natural polymer with diverse cosmetic and medical applications. Currently, HA is produced by overexpressing HA synthases from gram-negative Pasteurella multocida (encoded by pmHAS) or gram-positive Streptococcus equisimilis (encoded by seHasA) in various heterotrophic microbial production platforms. Here we introduced these two different types of HA synthase into the fast-growing cyanobacterium Synechococcus sp. PCC 7002 (Syn7002) to explore the capacity for producing HA in a photosynthetic system. Our results show that both HA synthases enable Syn7002 to produce HA photoautotrophically, but that overexpression of the soluble HA synthase (PmHAS) is less deleterious to cell growth and results in higher production. Genetic disruption of the competing cellulose biosynthetic pathway increased the HA titer by over 5-fold (from 14 mg/L to 80 mg/L) and the relative proportion of HA with molecular mass greater than 2 MDa. Introduction of glmS and glmU, coding for enzymes involved in the biosynthesis of the precursor UDP-N-acetylglucosamine, in combination with partial glycogen depletion, allowed photosynthetic production of 112 mg/L of HA in 5 days, an 8-fold increase in comparison to the initial PmHAS expressing strain. Addition of tuaD and gtaB (coding for genes involved in UDP-glucuronic acid biosynthesis) also improved the HA yield, albeit to a lesser extent. Overall our results have shown that cyanobacteria hold promise for the sustainable production of pharmaceutically important polysaccharides from sunlight and CO2.
AU - Zhang,L
AU - Selão,TT
AU - Nixon,PJ
AU - Norling,B
DO - 10.1016/j.algal.2019.101702
PY - 2019///
SN - 2211-9264
TI - Photosynthetic conversion of CO2 to hyaluronic acid by engineered strains of the cyanobacterium Synechococcus sp. PCC 7002
T2 - Algal Research
UR - http://dx.doi.org/10.1016/j.algal.2019.101702
UR - http://hdl.handle.net/10044/1/74536
VL - 44
ER -