Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: EC:2.7.1.1 (
hexokinase
)
5,274
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Over the past decades, considerable advances have been made in understanding the crucial role and the regulation of sucrose metabolism in plants. Among the various sucrose-catabolizing enzymes, alkaline/neutral invertases (A/N-Invs) have long remained poorly studied. However, recent findings have demonstrated the presence of A/N-Invs in various organelles in addition to the cytosol, and their importance for plant development and stress tolerance. A cytosolic (At-A/N-InvG, At1g35580) and a mitochondrial (At-A/N-InvA, At1g56560) member of the A/N-Invs have been analysed in more detail in Arabidopsis and it was found that At-A/N-InvA knockout plants show an even more severe growth phenotype than At-A/N-InvG knockout plants. The absence of either A/N-Inv was associated with higher oxidative stress defence gene expression, while transient overexpression of At-A/N-InvA and At-A/N-InvG in leaf mesophyll protoplasts down-regulated the oxidative stress-responsive
ascorbate peroxidase
2 (APX2) promoter. Moreover, up-regulation of the APX2 promoter by hydrogen peroxide or abscisic acid could be blocked by adding metabolizable sugars or ascorbate. A hypothetical model is proposed in which both mitochondrial and cytosolic A/N-Invs can generate glucose as a substrate for mitochondria-associated
hexokinase
, contributing to mitochondrial reactive oxygen species homeostasis.
...
PMID:Exploring the neutral invertase-oxidative stress defence connection in Arabidopsis thaliana. 2144 6
During their life cycle, trypanosomatids are exposed to stress conditions and adapt their energy and antioxidant metabolism to colonize their hosts. Strigomonas culicis is a monoxenous protist found in invertebrates with an endosymbiotic bacterium that completes essential biosynthetic pathways for the trypanosomatid. Our research group previously generated a wild-type H
2
O
2
-resistant (WTR) strain that showed improved mitochondrial metabolism and antioxidant defenses, which led to higher rates of Aedes aegypti infection. Here, we assess the biological contribution of the S. culicis endosymbiont and reactive oxygen species (ROS) resistance to oxidative and energy metabolism processes. Using high-throughput proteomics, several proteins involved in glycolysis and gluconeogenesis, the pentose phosphate pathway and glutathione metabolism were identified. The results suggest that ROS resistance decreases glucose consumption and indicate that the metabolic products from gluconeogenesis are key to supplying the protist with high-energy and reducing intermediates. Our hypothesis was confirmed by biochemical assays showing opposite profiles for glucose uptake and
hexokinase
and pyruvate kinase activity levels in the WTR and aposymbiotic strains, while the enzyme glucose-6P 1-dehydrogenase was more active in both strains. Regarding the antioxidant system,
ascorbate peroxidase
has an important role in H
2
O
2
resistance and may be responsible for the high infection rates previously described for A. aegypti. In conclusion, our data indicate that the energy-related and antioxidant metabolic processes of S. culicis are modulated in response to oxidative stress conditions, providing new perspectives on the biology of the trypanosomatid-insect interaction as well as on the possible impact of resistant parasites in accidental human infection.
...
PMID:Glycolytic profile shift and antioxidant triggering in symbiont-free and H
2
O
2
-resistant Strigomonas culicis. 3176 93
