Global proteome response ofSynechocystis6803 to extreme copper environments applied to control the activity of the induciblepetJpromoter

Abstract

Aims Cyanobacteria are prokaryotes performing oxygenic photosynthesis, and they can be engineered to harness solar energy for production of commodity and high‐value chemicals by means of synthetic biology. The Cu2+‐regulated petJ promoter (PpetJ), which controls the expression of the endogenous cytochrome c553, can be used for expression of foreign products in Synechocystis 6803. We aimed to disclose potential bottlenecks in application of the PpetJ in synthetic biology approaches. Methods and Results Quantitative label‐free mass spectrometry revealed global proteome changes which occurred during nutrient conditions which repress or activate of PpetJ in Synechocystis 6803. Conclusions Some irreversible proteome alterations were discovered due to the copper stress, including downregulation of the ribosomal proteins, significant changes in protein amounts of the cell surface layer and the outer and inner membranes. Significance and Impact of the Study This study revealed limitations in the use of PpetJ for biotechnological applications.

Reciprocal Effect of Copper and Iron Regulation on the Proteome of Synechocystis sp. PCC 6803

“…On the other hand, changes in PSII leads to down-regulation of phycobilisome-related protein expression ( Supplementary Table 1 ). These changes are consistent with previous reports ( Allen et al, 2008 ; Rochaix, 2011 ; Georg et al, 2017 ; Angeleri et al, 2019 ). In addition, the influence of copper or iron limitation on electron transfer will affect the formation of electrochemical gradients of protons inside and outside the TM, which in turn affects the synthesis of ATP by ATP synthase ( Ferguson and Sorgato, 1982 ; Van Walraven et al, 1985 ; Narayan et al, 2011 ).…”

“…We observed that porins Slr1841, Slr1908, and Slr0042 were significantly down-regulated under copper deduction and iron deduction conditions; Sll1550 was only significantly down-regulated under copper deduction conditions, while Sll1271 was not significantly down-regulated under copper deduction and iron deduction conditions ( Supplementary Table 2 ). This is consistent with previous results regarding copper- or iron-related stress ( Kowata et al, 2017 ; Angeleri et al, 2019 ; Kojima and Okumura, 2020 ). Studies have shown that the deletion of Sll0772, Sll1271, Sll1550, and Slr0042 retarded the growth of Synechocystis 6803 in iron-deficient media ( Qiu et al, 2018 ), suggesting that these porins are associated with iron uptake.…”

“…In addition, the influence of copper or iron limitation on electron transfer will affect the formation of electrochemical gradients of protons inside and outside the TM, which in turn affects the synthesis of ATP by ATP synthase ( Ferguson and Sorgato, 1982 ; Van Walraven et al, 1985 ; Narayan et al, 2011 ). The lack of ATP synthesis will trigger a series of differential expression of ATP-dependent proteins and related metabolic changes, including those of ribosomal proteins, various tRNA enzymes, and many other proteins, which are in agreements with the results of protein differential expression identified in this study ( Supplementary Table 2 ) and other reports ( Allen et al, 2008 ; Georg et al, 2017 ; Angeleri et al, 2019 ).…”

“…On one hand, many studies regarding cyanobacterial iron deduction stress have showed that iron deficiency can induce remodulation of photosystem complexes ( Michel and Pistorius, 2004 ; Latifi et al, 2005 ; Allen et al, 2008 ), and that the expression of iron stress-induced chlorophyll binding protein A (IsiA) ( Burnap et al, 1993 ), iron transporters ( Shcolnick et al, 2009 ), and alternative redox vectors were up-regulated ( Wood, 1978 ; Sandmann, 1985 ). On the other hand, copper deduction has been shown to reduce synthesis of plastoquinone and disintegration of thylakoid membranes ( Hutber et al, 1977 ; Guikema and Sherman, 1983 ; Ivanov et al, 2000 ; Sandström et al, 2002 ), and upregulate proteins involved in the main metabolic pathways, such as C and N fixation and carbohydrate metabolism ( Angeleri et al, 2019 ). Based on the extensive influence of iron and copper on cell metabolism ( Meisch and Bielig, 1975 ; Verma and Singh, 1990 ; Shavyrina et al, 2001 ; Pehlivan, 2018 ), we speculated that the association of Cu–Fe-related proteins may not only be limited to the electron transport chain, but may have a broader physiological impact to cyanobacteria.…”

Genetic, Genomics, and Responses to Stresses in Cyanobacteria: Biotechnological Implications

“…These proteome techniques were employed to study the responses to cold [489]; copper [490]; CO 2 limitation [491]; high light [492]; high or low temperature [469,[492][493][494]; high or low pH [495][496][497]; nitrogen-, phosphate, or sulfate-starvations [481,498,499]; metal stress [498,500,501]; salt stress [502][503][504][505][506][507]; and UV-B stress [508]. They also served to study the tolerance of Synechocystis PCC 6803 to butanol, ethanol, or hexane biofuels [488,[509][510][511][512], as well as to analyze cyanobacterial strains engineered for the production of butanol [511], ethanol [510], hexane [509], or 3-hydroxypropionic acid [513].…”