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Metabolic engineering of cyanobacteria has received attention as a sustainable strategy to convert carbon dioxide to fatty acid-derived chemicals that are widely used in the food and chemical industries. Herein, Synechococcus elongatus PCC 7942, a model cyanobacterium, was engineered for the first time to produce fatty acid ethyl esters (FAEEs) from CO 2 . Due to the lack of an endogenous ethanol production pathway and wax ester synthase (AftA) activity in the wild-type cyanobacterium, we metabolically engineered S. elongatus PCC 7942 by expressing heterologous AftA and introducing the ethanol pathway, resulting in detectable peaks of FAEEs. To enhance FAEE production, a heterologous phosphoketolase pathway was introduced in the FAEE-producing strain to supply acetyl-CoA. Subsequent optimization of the cyanobacterial culture with a hexadecane overlay resulted in engineered S. elongatus PCC 7942 that produced photosynthetic FAEEs (10.0 ± 0.7 mg/L/OD 730 ) from CO 2 . This paper is the first report of photosynthetic production of FAEEs from CO 2 in cyanobacteria.

Rising concentrations of atmospheric carbon dioxide ([CO2]) and subsequent changes in climate, including temperature and precipitation extremes, are very likely to alter pest pressures in both managed and unmanaged plant communities. Such changes in pest pressures can be positive (migration from a region) or negative (new introductions), but are likely to be accompanied by significant economic and environmental consequences. Recent studies indicate the range of invasive weeds such as kudzu and insects such as mountain pine beetle have already expanded to more northern regions as temperatures have risen. To reduce these consequences, a better understanding of the link between CO2/climate and pest biology is needed in the context of existing and new strategies for pest management. This paper provides an overview of the probable biological links and the vulnerabilities of existing pest management (especially chemical control) and provides a preliminary synthesis of research needs that could potentially improve the ability to monitor, mitigate, and manage pest impacts.

Among a number of impediments to a wider use of chemical leavening agents in bakery applications is the lack of standardized instrumentation capable of providing information on the rates of CO2 production from chemical leaveners in a format that is meaningful to both the technologist (i.e., the dough rate of reaction or DRR) and the researcher (e.g., in terms of fundamental unitskmol CO2 per kg of dough per s). This paper presents an original methodology to carry out the DRR test using a commercial pressuremeter, the Gassmart apparatus, and to model the kinetics of CO2 evolution of chemically leavened dough. Lean formula doughs were leavened at 27 and 39 degrees C with four chemical leavening systems containing sodium bicarbonate and one of four leavening acids, sodium acid pyrophosphate 40 (SAPP), adipic acid (ADA), potassium acid tartrate (KAT), and glucono-delta-lactone (GDL). Chemical kinetics theory was used to gain an insight into the reaction mechanisms responsible for the evolution of carbon dioxide from the leaveners. A first-order reaction kinetics model was found to be suitable for describing the neutralizing properties of GDL and ADA leavening systems, whereas a first-order reaction kinetics model for irreversible parallel reactions better described the leavening properties of the acidic salts KAT and SAPP.

In this paper, the NMR technique was used, for the first time, to accurately determine the diffusion coefficient D of CO(2)-dissolved molecules in various carbonated beverages, including champagne and sparkling wines. This parameter plays an important role concerning the bubble growth during its rise through the liquid (see ref 3). The diffusion coefficient of CO(2)-dissolved molecules D was compared with that deduced from the well-known Stokes-Einstein equation and found to significantly deviate from the general trend expected from Stokes-Einstein theory, i.e, D(SE) proportional, variant 1/eta, where D(SE) is the Stokes-Einstein diffusion coefficient and eta the viscosity of the liquid medium.