Search results for "Biochem"
showing 10 items of 20937 documents
Nitric oxide signalling in plants: interplays with Ca2+ and protein kinase
2008
International audience; Much attention has been paid to nitric oxide (NO)research since its discovery as a physiological mediator of plant defence responses. In recent years, newer roles have been attributed to NO, ranging from root development to stomatal closure. The molecular mechanisms underlying NO action in plants are just begun to emerge. The currently available data illustrate that NO can directly influence the activity of target proteins through nitrosylation and has the capacity to act as a Ca2+-mobilizing intracellular messenger. The interplay between NO and Ca2+ has important functional implications, expanding and enriching the possibilities for modulating transduction processes…
Cercospora beticola toxins. IX. Relationship between structure of beticolins, inhibition of plasma membrane H+ -ATPase and partition in lipid membran…
1996
Beticolins are yellow toxins produced by the fungus Cercospora beticola. The effect of one of them, beticolin-1, has been investigated on corn root plasma membrane H + -ATPase (EC 3.6.1.35) at different purification levels (plasma membrane fraction. partially, or highly purified enzyme). The results obtained demonstrated that (1) the purified proton pump was inhibited directly by low amounts of the toxin (I 50 =1.62 ± 0.18 μM), (2) the biological effects of beticolin-1 were similar to those of CBT (Cercospora beticola toxin). Furthermore, it was established that the efficiency of the different beticolins was clearly related to their ability to interact with the lipid bilayers, determined by…
Simultaneous determination of nine phytohormones in seaweed and algae extracts by HPLC-PDA.
2016
An RP-HPLC-PDA method for the simultaneous analysis of 9 compounds deriving from the phytohormones class was developed and optimized, namely indoleacetic acid (IAA), indolebutyric acid (IBA), phenyleacetic acid (PAA), naphtyleacetic acid (NAA), trans-zeatin (TZ), kinetin (KA), isopentenyladenine (IA), 6-benzylaminopurine (6-BA) and abscisic acid (ABA). Validation of the method was performed on the SFE-CO2 extract made out of the mixture of Baltic algae. The regression coefficients for plant hormones were in the range from 0.997 to 0.999. The LOD and LOQ were on the levels from 0.05–0.29 and 0.15–0.88 mg/L, respectively. Developed method was used for the separation and determination plant ho…
Effect of pH on malolactic fermentation in southern Italian wines
2018
This study investigated the influence of pH on malolactic fermentation (MLF) in white wines (adjusted to pH 3.2, 3.4 and 3.8, respectively) from Falanghina grapes and red wines (adjusted to pH 3.4 and 3.8, respectively) from Tintilia grapes. The wines were inoculated with Oenococcus oeni and Lactobacillus plantarum strains, and a mix of them (50:50), in red Tintilia only. The time required to complete MLF in wines from white Falanghina grapes at pH 3.4 and 3.8 was lower with O. oeni, while MLF did not occur at pH 3.2. In red Tintilia, MLF was always completed within 35 days; at high pH (3.8) a significant increase in histamine was detected, while the decrease in citric acid concentration ca…
An isoleucine-leucine substitution in chloroplastic acetyl-CoA carboxylase from green foxtail (Setaria viridis L. Beauv.) is responsible for resistan…
2002
The cDNAs encoding chloroplastic acetyl-CoA carboxylase (ACCase, EC 6.4.1.2) from three lines of Setaria viridis (L. Beauv.) resistant or sensitive to sethoxydim, and from one sethoxydim-sensitive line of Setaria italica (L. Beauv.) were cloned and sequenced. Sequence comparison revealed that a single isoleucine-leucine substitution discriminated ACCases from sensitive and resistant lines. Using near-isogenic lines of S. italica derived from interspecific hybridisation, we demonstrated that the transfer of the S. viridis mutant ACCase allele into a sethoxydim-sensitive S. italica line conferred resistance to this herbicide. We confirmed this result using allele-specific polymerase chain rea…
Effect on the Antioxidant, Lipoperoxyl Radical Scavenger Capacity, Nutritional, Sensory and Microbiological Traits of an Ovine Stretched Cheese Produ…
2021
An innovative ovine cheese enriched with red grape pomace powder (GPP) was produced to improve the functional properties of Vastedda cheese typology. Vastedda cheese making was performed adding GPP and four selected Lactococcus lactis strains (Mise36, Mise94, Mise169 and Mise190). For each strain, 40 L of pasteurized ewe’s milk was divided into two aliquots representing control and experimental trials. Control cheese (CC) production did not contain GPP, while the experimental cheese (EC) production was enriched with 1% (w/w) GPP. GPP did not slow down starter development and acid generation. Plate counts and randomly amplified polymorphic DNA (RAPD)-PCR analysis confirmed the dominance of t…
Silver Nanoparticles Affect Functional Bioenergetic Traits in the Invasive Red Sea Mussel Brachidontes pharaonis
2016
We investigated the functional trait responses to 5 nm metallic silver nanoparticle (AgNPs) exposure in the Lessepsian-entry bivalveB. pharaonis. Respiration rate (oxygen consumption), heartbeat rate, and absorption efficiency were evaluated across an 8-day exposure period in mesocosmal conditions. Basal reference values from not-exposed specimens were statistically compared with those obtained from animals treated with three sublethal nanoparticle concentrations (2 μg L−1, 20 μg L−1, and 40 μg L−1). Our data showed statistically significant effects on the average respiration rate ofB. pharaonis. Moreover, complex nonlinear dynamics were observed as a function of the concentration level and…
The Selaginella Genome Identifies Genetic Changes Associated with the Evolution of Vascular Plants
2011
International audience; Vascular plants appeared ~410 million years ago, then diverged into several lineages of which only two survive: the euphyllophytes (ferns and seed plants) and the lycophytes. We report here the genome sequence of the lycophyte Selaginella moellendorffii (Selaginella), the first nonseed vascular plant genome reported. By comparing gene content in evolutionarily diverse taxa, we found that the transition from a gametophyte- to a sporophyte-dominated life cycle required far fewer new genes than the transition from a nonseed vascular to a flowering plant, whereas secondary metabolic genes expanded extensively and in parallel in the lycophyte and angiosperm lineages. Sela…
From elicitins to lipid-transfer proteins: a new insight in cell signalling involved in plant defence mechanisms.
2002
Elicitins and lipid-transfer proteins are small cysteine-rich lipid-binding proteins secreted by oomycetes and plant cells, respectively, that share some structural and functional properties. In spite of intensive work on their structure and diversity at the protein and genetic levels, the precise biological roles of lipid-transfer proteins remains unclear, although the most recent data suggest a role in somatic embryogenesis, in the formation of protective surface layers and in defence against pathogens. By contrast, elicitins are known elicitors of plant defence, and recent work demonstrating that elicitins and lipid-transfer proteins share the same biological receptors gives a new perspe…
Escaping the evolutionary trap: Can size-related contest advantage compensate for juvenile mortality disadvantage when parasitoids develop in unnatur…
2021
Abstract The quality of hosts for a parasitoid wasp may be influenced by attributes such as host size or species, with high quality for successful development usually coincident with high quality for larger offspring. This is not always the case: for the Scelionid wasp Trissolcus basalis, oviposition in eggs of the Brown Marmorated Stink Bug, Halyomorpha halys, rather than of the normal host, the Southern Green Stink Bug, Nezara viridula, leads to lower offspring survival, but survivors can be unusually large. Adult female T. basalis engage in contests for host access. As larger contestants are typically favoured in contests between parasitoids, the larger size of surviving offspring may co…