The threat to global food security of stagnating yields and population growth makes increasing crop productivity a critical goal over the coming decades. One key target for improving is efficiency photosynthesis. Central photosynthesis Rubisco, which but often rate-limiting component. Here, we present full Rubisco catalytic properties measured at three temperatures 75 plants species representing both crops undomesticated from diverse climates. Some newly characterized Rubiscos were naturally...

Improving global yields of important agricultural crops is a complex challenge. Enhancing yield and resource use by engineering improvements to photosynthetic carbon assimilation one potential solution. During the last 40 million years C(4) photosynthesis has evolved multiple times, enabling plants evade catalytic inadequacies CO(2)-fixing enzyme, ribulose-1,5-bisphosphate carboxylase/oxygenase (rubisco). Compared with their C(3) ancestors, combine faster rubisco biochemical...

Summary Sub‐Saharan Africa is projected to see a 55% increase in food demand by 2035, where cassava ( Manihot esculenta ) the most widely planted crop and major calorie source. Yet, yield this region has not increased significantly for 13 yr. Improvement of genetic potential, basis first Green Revolution, could be realized improving photosynthetic efficiency. First, factors limiting photosynthesis their variability within extant germplasm must understood. Biochemical diffusive limitations...

Rubisco is a major target for improving crop photosynthesis and yield, yet natural diversity in catalytic properties of this enzyme poorly understood. from 25 genotypes the Triticeae tribe, including wild relatives bread wheat (Triticum aestivum), were surveyed to identify superior enzymes crop. In vitro carboxylation velocity (Vc), Michaelis–Menten constants CO2 (Kc) O2 (Ko) specificity factor (Sc/o) measured at 35 °C. Vc Kc correlated positively, while Sc/o inversely related. large subunit...

Introducing components of algal carbon concentrating mechanisms (CCMs) into higher plant chloroplasts could increase photosynthetic productivity. A key component is the Rubisco-containing pyrenoid that needed to minimise CO2 retro-diffusion for CCM operating efficiency. Rubisco in Arabidopsis was re-engineered incorporate sequence elements are thought be essential recruitment pyrenoid, namely small subunit (SSU, encoded by rbcS) or only surface-exposed SSU α-helices. Leaves rbcs mutants...

Summary The Triticum aestivum (wheat) genome encodes three isoforms of Rubisco activase (Rca) differing in thermostability, which could be exploited to improve the resilience this crop global warming. We hypothesized that elevated temperatures would cause an increase relative abundance heat‐stable Rca1β. Wheat plants were grown at 25° C : 18°C (day night) and exposed heat stress (38° 22°C) for up 5 d pre‐anthesis. Carbon (C) assimilation, activity, CA1Pase transcripts Rca1β, Rca2β, Rca2α,...

<ns4:p>Photosynthesis is the basis of primary productivity on planet. Crop breeding has sustained steady improvements in yield to keep pace with population growth increases. Yet these advances have not resulted from improving photosynthetic process<ns4:italic>per se</ns4:italic>but rather altering way carbon partitioned within plant. Mounting evidence suggests that rate at which crop yields can be boosted by traditional plant approaches wavering, and they may reach a “yield ceiling”...

Green algae expressing a carbon-concentrating mechanism (CCM) are usually associated with Rubisco-containing micro-compartment, the pyrenoid. A link between small subunit (SSU) of Rubisco and pyrenoid formation in Chlamydomonas reinhardtii has previously suggested that specific RbcS residues could explain occurrence green algae. phylogeny was used to compare protein sequence CCM distribution across positive selection estimated. For six streptophyte algae, catalytic properties, affinity for...

Engineering the small subunit of key CO 2 -fixing enzyme Rubisco (SSU, encoded by rbcS ) in plants currently poses a significant challenge, as many have polyploid genomes and SSUs are large multigene families. Here, we used CRISPR-Cas9-mediated genome editing approach to simultaneously knock-out multiple homologs model tetraploid crop tobacco ( Nicotiana tabacum cv . Petit Havana). The three rbcS_S1a, rbcS_S1b rbcS_T1 account for at least 80% total expression tobacco. In this study, two...

Abstract Interventions to increase crop radiation use efficiency rely on understanding of how biochemical and stomatal limitations affect photosynthesis. When leaves transition from shade high light, slow increases in maximum Rubisco carboxylation rate conductance limit net CO 2 assimilation for several minutes. However, as stomata open intercellular [CO ] increases, so electron transport could also become limiting. Photosynthetic were evaluated three important Brassica crops: rapa ,...

Photosynthetic inefficiencies limit the productivity and sustainability of crop production resilience agriculture to future societal environmental challenges. Rubisco is a key target for improvement as it plays central role in carbon fixation during photosynthesis remarkably inefficient. Introduction mutations chloroplast-encoded large subunit rbcL particular interest improving catalytic activity efficiency enzyme. However, manipulation hampered by its location plastome, with many species...

Abstract Regulating the central CO2-fixing enzyme Rubisco is as complex its ancient reaction mechanism and involves interaction with a series of cofactors auxiliary proteins that activate catalytic sites maintain activity. A key component among regulatory mechanisms binding sugar phosphate derivatives inhibit Removal inhibitors via action activase required to restore competency. In addition, specific phosphatases dephosphorylate newly released inhibitors, rendering them incapable sites. The...

A vital crop for sub-Saharan Africa, cowpea productivity is threatened by climate change, including increased heatwave intensity, duration, and frequency. Rubisco activase (Rca) a key molecular chaperone that maintains activity due to its thermal sensitivity target improving resilience. We identified characterised four Rca isoforms in Vigna unguiculata (L.) Walp. cv. IT97K-499-35 vitro : Rca1β, Rca8α, Rca10α Rca10β. Cowpea leaf plant growth traits were also investigated during 5-day +10 °C...

Much of the research aimed at improving photosynthesis and crop productivity attempts to overcome shortcomings primary CO2-fixing enzyme Rubisco. Cyanobacteria utilize a CO2-concentrating mechanism (CCM), which encapsulates Rubisco with poor specificity but relatively fast catalytic rate within carboxysome microcompartment. Alongside active transport bicarbonate into cell localization carbonic anhydrase shell Rubisco, cyanobacteria are able limitations via high-CO2 environment. As part...

Oligomerization is a core structural feature that defines the form and function of many proteins. Most proteins molecular complexes; however, there remains dearth diversity-driven studies investigating evolutionary trajectory these assemblies. Ribulose-1,5-bisphosphate carboxylase-oxygenase (RuBisCO) one such enzyme adopts multiple assemblies, although origins distribution its different oligomeric states remain cryptic. Here, we retrace evolution ancestral extant II RuBisCOs, revealing...

Rubisco activity is highly regulated and frequently limits carbon assimilation in crop plants. In the chloroplast, various metabolites can inhibit or modulate by binding to its catalytic allosteric sites, but this regulation complex still poorly understood. Using rice Rubisco, we characterised impact of chloroplast which could interact with activity, including photorespiratory intermediates, carbohydrates, amino acids; as well specific sugar-phosphates known - CABP (2-carboxy-d-arabinitol...

To identify if culture conditions affect the chemical composition of exopolysaccharide (EPS) produced by Aureobasidium pullulans.In batch airlift and continuously stirred tank (CSTR) reactors EPS with low (0.13 g l(-1) N) initial NaNO(3) or (NH(4))(2)SO(4) levels contained pullulan, maltotriose as its major component, similar to that synthesized in reactor high (0.78 levels. CSTR grown cultures little possibly because a population shift from unicells mycelium. This difference may explain why...

The primary CO2-fixing enzyme Rubisco limits the productivity of plants. small subunit (SSU) can influence overall levels and catalytic efficiency, is now receiving increasing attention as a potential engineering target to improve performance Rubisco. However, SSUs are encoded by family nuclear rbcS genes in plants, which makes them challenging engineer study. Here we have used CRISPR/Cas9 [clustered regularly interspaced palindromic repeats (CRISPR)/CRISPR-associated protein 9] T-DNA...

Rates of carbon dioxide assimilation through photosynthesis are readily modeled using the Farquhar, von Caemmerer, and Berry (FvCB) model based on biochemistry initial Rubisco-catalyzed reaction net C3 photosynthesis. As models CO2 rate used more broadly for simulating among species across scales, it is increasingly important that their temperature dependencies accurately parameterized. A vital component FvCB model, photorespiratory compensation point (Γ *), combines Rubisco with...

ABSTRACT Adult mouse DRG neurones have been maintained for 14 days in cultures where non-neuronal cell proliferation was inhibited by the inclusion of 5xlO~6/iM-cytosine arabinoside (AraC) medium from onset culture. On uncoated plastic neurone numbers significantly declined absence outgrowth compared with uninhibited co-cultures. However, when were presence AraC on certain coated surfaces this decrease not observed. Combinations fibronectin (FN) and laminin (LAM) proved most effective 7...

Rubisco catalyzes the fixation of CO2 into organic compounds that are used for plant growth and production agricultural products, specific sugar-phosphate derivatives bind tightly to active sites Rubisco, locking enzyme in a catalytically inactive conformation. 2-carboxy-d-arabinitol-1-phosphate phosphatase (CA1Pase) dephosphorylates such tight-binding inhibitors, contributing maintenance activity. Here, we investigated hypothesis overexpressing ca1pase would decrease abundance thereby...