Search results for "PPE"

Transcriptional response of Erwinia amylovora to copper shock: in vivo role of the copA gene

2017

Fire blight is a devastating plant disease caused by the bacterium Erwinia amylovora, and its control is frequently based on the use of copper-based compounds whose mechanisms of action are not well known. Consequently, in this article, we investigate the response of E. amylovora to copper shock by a whole-genome microarray approach. Transcriptional analyses showed that, in the presence of copper, 23 genes were increased in expression; these genes were classified mainly into the transport and stress functional categories. Among them, the copA gene was strongly induced and regulated in a finely tuned manner by copper. Mutation of copA, soxS, arcB, yjcE, ygcF, yhhQ, galF and EAM_3469 genes re…

Are glutamate and asparagine necessary for tyrosinase activity of type-3 copper proteins?

2018

Abstract Type-3 copper proteins (T3CPs) are complex proteins which share similar active sites. Two copper atoms (CuA and CuB) bind dioxygen as a peroxide in a side on coordination. This protein family comprises the enzymes tyrosinase and catechol oxidase as well as the oxygen transporter hemocyanin. T3CPs occur in almost all organisms and exhibit a number of essential functions. In particular, they are involved in all kinds of enzymatic browning reactions and immune defense. The chemical basis of the two catalytic processes, i.e., the o-hydroxylation of monophenols and the two-electron oxidation to o-quinones, is still discussed. Investigations on natural enzymes with known crystal structur…

Modulation of mitochondriotropic properties of cyanine dyes by in organello copper-free click reaction

2017

Cyanine (Cy) dyes show a general propensity to localize in polarized mitochondria. This mitochondriotropism was used to perform a copper-free click reaction in the mitochondria of living cells. The in organello reaction of dyes Cy3 and Cy5 led to a product that was easily traceable by Forster resonance energy transfer (FRET). As determined by confocal laser scanning microscopy, the Cy3-Cy5 conjugate showed enhanced retention in mitochondria, relative to that of the starting compounds. This enhancement of a favorable property can be achieved by synthesis in organello, but not outside mitochondria.

Pre-imaginal conditioning alters adult sex pheromone response in Drosophila

2018

https://peerj.com/articles/5585/#supplemental-information; International audience; Pheromones are chemical signals that induce innate responses in individuals of the same species that may vary with physiological and developmental state. In Drosophila melanogaster, the most intensively studied pheromone is 11-cis-vaccenyl acetate (cVA), which is synthezised in the male ejaculatory bulb and is transferred to the female during copulation. Among other effects, cVA inhibits male courtship of mated females. We found that male courtship inhibition depends on the amount of cVA and this effect is reduced in male flies derived from eggs covered with low to zero levels of cVA. This effect is not obser…

FRET-based dynamic structural biology: Challenges, perspectives and an appeal for open-science practices.

2021

International audience; Single-molecule FRET (smFRET) has become a mainstream technique for studying biomolecular structural dynamics. The rapid and wide adoption of smFRET experiments by an ever- increasing number of groups has generated significant progress in sample preparation, measurement procedures, data analysis, algorithms and documentation. Several labs that employ smFRET approaches have joined forces to inform the smFRET community about streamlining how to perform experiments and analyze results for obtaining quantitative information on biomolecular structure and dynamics. The recent efforts include blind tests to assess the accuracy and the precision of smFRET experiments among d…

Natural upper anterior teeth display an increasing proportion in mesio-distal direction

2019

Background This study aimed to determine the esthetic proportion of six natural upper anterior teeth in northeastern Thai population as well as the level of esthetic satisfaction of distinct tooth proportions. Material and Methods Front-view photographs were taken from participants living in the Northeastern Thailand (n=140) of the 18-35 years of age. Computerized program was used for measuring the size of each tooth. All subjects also scored the satisfaction level of different photographs portraying 4 proportions of anterior teeth (golden proportion, 70% RED, 80% RED, and an increasing proportion). Results We found that proportion of lateral-to-central incisor and canine-to-lateral incisor…

Influence of glucagon-like peptide 2 on energy homeostasis

2016

Glucagon like peptide-2 (GLP-2) is a gastrointestinal hormone released from enteroendocrine L-type cells together with glucagon like peptide-1 in response to dietary nutrients. GLP-2 acts through a specific receptor, the GLP-2 receptor, mainly located in the gut and in the brain. Classically, GLP-2 is considered a trophic hormone involved in the maintenance of intestinal epithelial morphology and function. This role has been targeted for therapies promoting repair and adaptive growth of the intestinal mucosa. Recently, GLP-2 has been shown to exert beneficial effects on glucose metabolism specially in conditions related to increased uptake of energy, such as obesity. Several actions of GLP-…

Histidine tracts in human transcription factors: insight into metal ion coordination ability

2017

Consecutive histidine repeats are chosen both by nature and by molecular biologists due to their high affinity towards metal ions. Screening of the human genome showed that transcription factors are extremely rich in His tracts. In this work, we examine two of such His-rich regions from forkhead box and MAFA proteins—MB3 (contains 18 His) and MB6 (with 21 His residues), focusing on the affinity and binding modes of Cu2+ and Zn2+ towards the two His-rich regions. In the case of Zn2+ species, the availability of imidazole nitrogen donors enhances metal complex stability. Interestingly, an opposite tendency is observed for Cu2+ complexes at above physiological pH, in which amide nitrogens part…

2016

Context: Roux-en-Y gastric bypass (RYGB) surgery is an effective long-term intervention for weight loss maintenance, reducing appetite, and also food reward, via unclear mechanisms. Objective: To investigate the role of elevated satiety gut hormones after RYGB, we examined food hedonic-reward responses after their acute post-prandial suppression. Design: These were randomized, placebo-controlled, double-blind, crossover experimental medicine studies. Patients: Two groups, more than 5 months after RYGB for obesity (n = 7–11), compared with nonobese controls (n = 10), or patients after gastric banding (BAND) surgery (n = 9) participated in the studies. Intervention: Studies were performed aft…

Women in LOVe: Lacto-Ovo-Vegetarian Diet Rich in Omega-3 Improves Vasomotor Symptoms in Postmenopausal Women. An Exploratory Randomized Controlled Tr…

2019

Objective:In the postmenopausal period, most women suffer vasomotor symptoms (VMS). It is well-known that VMS can worsen the quality of life. Diet seems to play a relevant role in the development of VMS, but the effect of diet on VMS is mainly limited to observational studies, and analyses of nutritional supplements. The aim of this study was thus to determine the efficacy of a lactoovo- vegetarian (LOVe) diet rich in omega-3 fatty acids vs. a lacto-ovo-vegetarian diet rich in EVO (extra-virgin olive oil) in reducing VMS frequency in postmenopausal women.Methods:A two-arms (lacto-ovo-vegetarian diet with EVO vs. lacto-ovo-vegetarian diet rich in omega-3) randomized-controlled trial with a f…