Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:2.7.1.1 (hexokinase)
 5,274 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Noctiluca scintillans is a bloom-forming dinoflagellate, which is widely distributed in the global coastal seas. Associated bacteria have been proven to be essential for the survival and growth of zooplanktons. However, the diversity and function of bacteria associated with Noctiluca scintillans are under studied and largely unknown. Here, we examined the diversity and function of bacteria associated with field-acquired and laboratory-maintained Noctiluca cells. Our results showed that the bacterial communities associated with the laboratory-maintained Noctiluca were dominated by Rhodobacterales, whereas those associated with the field-acquired Noctiluca varied over time. In addition, major Noctiluca-associated bacteria had low relative abundance in the ambient environment. We also observed that when field-acquired Noctiluca were cultivated with a mono-species food source, there was a shift in the associated bacterial communities. Metagenomic analysis showed that genes involved in DNA replication/repair and osmotic regulation were more abundant than other genes in the Noctiluca-associated bacterial community. Furthermore, the associated bacteria were able to degrade various complex carbohydrates and actively participate in the nitrogen cycle in their host cells. In addition, a draft genome of the Rickettsiaceae strain was recovered, and we showed that the genome did not contain genes encoding hexokinase and phosphoglucomutase, two key enzymes involved in glucose utilization. Instead, the primary energy sources of this bacteria were shown to be glutamate, glutamine and pyruvate, which might be obtained from the host. We suggest that in return, the Rickettsiaceae strain is likely to provide cofactors and amino acids to the host. This study highlights the spatial and temporal complexity of bacterial communities associated with Noctiluca, and provides valuable insights into the interaction between a host and its associated bacteria.
 ...
PMID:Rare bacteria in seawater are dominant in the bacterial assemblage associated with the Bloom-forming dinoflagellate Noctiluca scintillans. 3181 56

It was anticipated that wheat net photosynthesis would rise under elevated CO2, and that this would alter the progress of senescence due to the unbalance of carbohydrates and nitrogen. Our study showed that ear carbon sink was limited, and sugar was accumulated, hexokinase activities and levels of phosphorylated sugar were increased within the flag leaves, grain nitrogen sink capacity was enhanced, and flag leaf senescence was accelerated under elevated CO2. However, if the ear of the main stem was covered, these responses to elevated CO2 were absent, and the senescence of flag leaf was not accelerated by elevated CO2. Thus, it appeared that elevated CO2 accelerated the rate of flag leaf senescence, depending on ear photosynthesis. The ears have far higher enhancement of net photosynthesis than flag leaves, and the role of the flag leaf relative to the ear was declined in supplying C assimilation to grain under elevated CO2. This indicates that as CO2 rises, the grain sink needs the N more than C assimilate from flag leaf, so the declining rates of N% and soluble proteins concentration were markedly accelerated under elevated CO2 conditions. This suggests that, the large increase in ear net photosynthesis accelerated grain filling, accelerated remobilising N within flag leaf as the result of the greater grain nitrogen sink capacity. In addition, as the result of grain carbon sink limitation, it limited the export of flag leaf sucrose and enhanced sugar cycling, which was the signal to accelerate leaf senescence. Hence, elevated CO2 subsequently accelerates senescence of flag leaf.
 ...
PMID:Elevated CO2 accelerates flag leaf senescence in wheat due to ear photosynthesis which causes greater ear nitrogen sink capacity and ear carbon sink limitation. 3268 47

Soluble sugars play important roles in plant development and stress response, and the nitrogen supply level can affect the among-organ distribution and metabolism of sugar in plants and, in turn, plant growth. To explore the adaptive response of apple root growth to nitrogen supply and its relationship with sugar metabolism, we used a hydroponic culture system to study how the nitrogen supply affects soluble sugar concentrations and sugar metabolism in apple roots. In hydroponic seedlings of Malus hupehensis, low nitrogen application caused rapid and vigorous proliferation of lateral roots, and the transcript levels of MdSOT1 and MdSUT3, which are involved in photoassimilate unloading in roots, were upregulated. The accumulation of sorbitol and sucrose in the fine roots was higher, and the activities of sucrose synthase, invertase and sorbitol dehydrogenase, which are involved in the degradation of sucrose and sorbitol, were significantly increased under a low nitrogen supply. Genes involved in sugar degradation, such as MdSDH1, MdSuSy5, and MdNINV3, play important roles in the efficient use of sorbitol and sucrose under nitrogen deficiency. Additionally, the activity of fructokinase and hexokinase, which are involved in hexose phosphorylation, and transcript levels of MdFRK2 and MdHK3 were significantly upregulated under nitrogen deficiency, and the hexose phosphate products F6P and G6P accumulated greatly in the roots. These results showed that the sugar metabolism capability and sink strength of the roots increased under low nitrogen, indicating that low nitrogen promotes the utilization of sugar in the roots to meet the demand for sugar under rapid root growth.
 ...
PMID:Carbohydrate metabolism and transport in apple roots under nitrogen deficiency. 3282 46

Yarrowia lipolytica is an important industrial microorganism used for the production of oleochemicals. The design of effective biotechnological processes with this cell factory requires an in-depth knowledge of its metabolism. Here we present a transcriptomic study of Y. lipolytica grown in the presence of glycerol and glucose, and mixture of both at different carbon to nitrogen ratios. It emerged that the transcriptomic landscape of Y. lipolytica is more sensitive to the nitrogen availability than to the utilized carbon source, as evidenced by more genes being differentially expressed in lower carbon to nitrogen ratio. Specifically, expression of hexokinase (HXK1) is significantly susceptible to changes in nitrogen concentrations. High HXK1 expression in low nitrogen seems to impact other genes which are implicated in tricarboxylic acid cycle and erythritol biosynthesis. We further show that expression of HXK1 and two genes belonging to the sugar porter family might be controlled by GATA-like zinc-finger proteins.
 ...
PMID:Nitrogen as the major factor influencing gene expression in Yarrowia lipolytica. 3292 79


<< Previous 1 2 3 4 5 6 7