Molecular Level Changes Research Articles

Molecular level changes during suppression of Rhizoctonia solani growth by humic substances and relationships with chemical structure

Elucidation of the inhibitory effects of humic substances (HSs) on phytopathogenic fungi and the underlying molecular mechanisms are highly important for improved biocontrol. In this study, we investigated the growth suppression, morphological characteristics, transcriptomic sequence, and radical signals of Rhizoctonia solani following HS addition (50 mg/L). Through mycelial cultured experiment, mycelia growth of R. solani had been suppressed with HS addition, and the inhibition rate was 24.88 ± 0.11% compared to the control. Field emission-scanning electron microscopy showed increased and superimposed branching mycelial growth, with a shriveled appearance. RNA samples of R. solani cultured with or without HSs were both extracted to examine the sequence on molecular level by Illumina HiSeq sequencing platform. RNA sequencing analysis revealed 175 differentially expressed genes (DEGs; 111 upregulated and 64 downregulated) between the HSs treatment and control. The upregulated unigenes were annotated and significantly enriched to three molecular processes: vitamin B6 metabolism, ABC transporters, and glutathione metabolism, while the downregulated unigenes were annotated to carbohydrate metabolism, but not significantly enriched. Real time-quantitative polymerase chain reaction analysis showed that the unigenes related to hexokinase, glucose-6-phosphate isomerase, glutathione synthase, and glutathione reductase were significantly decreased (by 60.03%, 70.70%, 60.33%, and 57.59%, respectively), while those related to glutathione S-transferase were significantly increased (2.66-fold). The electron paramagnetic resonance spectra showed that HSs induced increased the intensity of radical signals of R. solani in a cultured system increased by 59.56% compared to CK (without HSs addition). Network analysis based on DEGs expression and the chemical structure of HSs revealed that the carbonyl moiety in HSs formed the most links with nodes of the DEGs (sum of the links of positive and negative effects = 70), implicating this structure as the active fraction responsible for the inhibitory effect. This study provides molecular and chemical evidence of the biofungicidal activity of HSs with the potential for practical application.

15959 Topically applied lotions containing fatty acids provide nourishment to the skin through maturation of the lipid matrix

Background: Lotions containing a mixture of glycerin, petroleum jelly, and fatty acids have been shown to improve skin moisturization, alleviate visual dryness, and result in a healthier skin barrier over time. A fuller understanding of the molecular level changes which occur with such improvements has been lacking, particularly in the understanding of lipids, but would provide insights to allow the development of more efficacious products.

Expression and Signaling of β-Adrenoceptor Subtypes in the Diabetic Heart.

Diabetes is a chronic, endocrine disorder that effects millions of people worldwide. Cardiovascular complications are the major cause of diabetes-related morbidity and mortality. Cardiac β1- and β2-adrenoceptor (AR) stimulation mediates positive inotropy and chronotropy, whereas β3-AR mediates negative inotropic effect. Changes in β-AR responsiveness are thought to be an important factor that contributes to the diabetic cardiac dysfunction. Diabetes related changes in β-AR expression, signaling, and β-AR mediated cardiac function have been studied by several investigators for many years. In the present review, we have screened PubMed database to obtain relevant articles on this topic. Our search has ended up with wide range of different findings about the effect of diabetes on β-AR mediated changes both in molecular and functional level. Considering these inconsistent findings, the effect of diabetes on cardiac β-AR still remains to be clarified.

Transition in the Acid–Base Component of Surface Free Energy of Ice upon the Premelting of Its Second Molecular Bilayer

Molecular disordering of the ice surface occurs below the bulk melting temperature of 273 K, termed surface premelting. The top-most molecular layer begins gradually premelting at 200 K, and has been linked to its low coefficient of friction through an increase in molecular mobility. The second molecular bilayer premelts around 257 K, but no study has linked this transition to a change in any macroscopic phenomena. Here, we show that the thermodynamic work of adhesion between polydimethylsiloxane (PDMS) and ice changes abruptly at 257.0 $\pm$ 0.1 K. Surface-sensitive sum frequency generation spectroscopy shows that there are no molecular level changes at the PDMS surface or the ice-PDMS interface near the transition in adhesion, indicating that the transition arises from changes of the ice surface. Using existing contact angle data in the literature, we show that this transition is due to a decrease in the acid-base component of the surface free energy of ice by 17 $\pm$ 2 mJ/m$^2$ at 257.0 $\pm$ 0.1 K. The change in surface energy provides a possible explanation for a variety of unexplained phenomena seen across the literature including ice adhesion, friction, and the morphology of snowflakes.

Multi-modal surface analysis of porous films under operando conditions

Practical catalysts with a porous framework, such as zeolites, host catalytic reactions at active sites engrained in the pores and channels of the scaffold. The mechanism of interaction at these active sites, defining catalyst performance, remains elusive, in large part, due to the lack of surface characterization methods available for thick films or powders. Here, we present thin film analogs of practical catalysts that allow for the implementation of surface characterization tools, including advanced microscopy and operando spectroscopy methodologies. Specifically, we investigated bilayer silica, MFI nanosheets, and UiO-66 thin films using a multi-modal approach addressing film growth, characterization, and gas adsorption aimed at understanding catalytic activity, reactivity, and selectivity properties, as defined by molecular-level changes in the reaction mechanism.

Effects of Fungicide and Herbicide Chemical Exposure on Apis and Non-Apis Bees in Agricultural Landscape

Fungicide and herbicide chemistries are commonly applied in agricultural production systems and other agricultural landscapes during flowering periods which are concurrent with the timing of bee-dependent pollination services in many plant species. As a result, bees can be exposed to these pesticides while foraging crops and other flowering plants in the landscape where they have been administered. Laboratory and semi-field studies simulating these pesticide exposure scenarios have demonstrated lethal and sub-lethal impacts to both Apis and non-Apis species of domesticated bees. Exposure to fungicides and herbicides has also been attributed to bee genetic and molecular level changes in some cases. Herbicides can also indirectly impact bees as a result of decreasing weeds and other flowering plants that serve as nutrient resources for foraging bees. We analyze a series of recent studies concerning the toxicity of fungicides and herbicides to Apis and non-Apis bees as a basis for forming our views on key priorities regarding the direction of future research initiatives in this area. Exploring impacts of agricultural pesticides beyond insecticides to bees is timely given documented bee declines in the last decade and resulting widescale interest in identifying different drivers of these declines among the biological and ecological scientific communities.

Retene, pyrene and phenanthrene cause distinct molecular-level changes in the cardiac tissue of rainbow trout (Oncorhynchus mykiss) larvae, part 2 – Proteomics and metabolomics

Polycyclic aromatic hydrocarbons (PAHs) are global contaminants of concern. Despite several decades of research, their mechanisms of toxicity are not very well understood. Early life stages of fish are particularly sensitive with the developing cardiac tissue being a main target of PAHs toxicity. The mechanisms of cardiotoxicity of the three widespread model polycyclic aromatic hydrocarbons (PAHs) retene, pyrene and phenanthrene were explored in rainbow trout (Oncorhynchus mykiss) early life stages. Newly hatched larvae were exposed to sublethal doses of each individual PAH causing no detectable morphometric alterations. Changes in the cardiac proteome and metabolome were assessed after 7 or 14 days of exposure to each PAH. Phase I and II enzymes regulated by the aryl hydrocarbon receptor were significantly induced by all PAHs, with retene being the most potent compound. Retene significantly altered the level of several proteins involved in key cardiac functions such as muscle contraction, cellular tight junctions or calcium homeostasis. Those findings were quite consistent with previous reports regarding the effects of retene on the cardiac transcriptome. Significant changes in proteins linked to iron and heme metabolism were observed following exposure to pyrene. While phenanthrene also altered the levels of several proteins in the cardiac tissue, no clear mechanisms or pathways could be highlighted. Due to high variability between samples, very few significant changes were detected in the cardiac metabolome overall. Slight but significant changes were still observed for pyrene and phenanthrene, suggesting possible effects on several energetic or signaling pathways. This study shows that early exposure to different PAHs can alter the expression of key proteins involved in the cardiac function, which could potentially affect negatively the fitness of the larvae and later of the juvenile fish.

Retene, pyrene and phenanthrene cause distinct molecular-level changes in the cardiac tissue of rainbow trout (Oncorhynchus mykiss) larvae, part 1 – Transcriptomics

Polycyclic aromatic hydrocarbons (PAHs) are contaminants of concern that impact every sphere of the environment. Despite several decades of research, their mechanisms of toxicity are still poorly understood. This study explores the mechanisms of cardiotoxicity of the three widespread model PAHs retene, pyrene and phenanthrene in the rainbow trout (Oncorhynchus mykiss) early life stages. Newly hatched larvae were exposed to each individual compound at sublethal doses causing no significant increase in the prevalence of deformities. Changes in the cardiac transcriptome were assessed after 1, 3, 7 and 14 days of exposure using custom Salmo salar microarrays. The highest number of differentially expressed genes was observed after 1 or 3 days of exposure, and retene was the most potent compound in that regard. Over-representation analyses suggested that genes related to cardiac ion channels, calcium homeostasis and muscle contraction (actin binding, troponin and myosin complexes) were especially targeted by retene. Pyrene was also able to alter similar myosin-related genes, but at a different timing and in an opposite direction, suggesting compound-specific mechanisms of toxicity. Pyrene and to a lesser extent phenanthrene were altering key genes linked to the respiratory electron transport chain and to oxygen and iron metabolism. Overall, phenanthrene was not very potent in inducing changes in the cardiac transcriptome despite being apparently metabolized at a slower rate than retene and pyrene. The present study shows that exposure to different PAHs during the first few days of the swim-up stage can alter the expression of key genes involved into the cardiac development and function, which could potentially affect negatively the fitness of the larvae in the long term.

Integrated network modeling approach defines key metabolic responses of soil microbiomes to perturbations

The soil environment is constantly changing due to shifts in soil moisture, nutrient availability and other conditions. To contend with these changes, soil microorganisms have evolved a variety of ways to adapt to environmental perturbations, including regulation of gene expression. However, it is challenging to untangle the complex phenotypic response of the soil to environmental change, partly due to the absence of predictive modeling frameworks that can mechanistically link molecular-level changes in soil microorganisms to a community’s functional phenotypes (or metaphenome). Towards filling this gap, we performed a combined analysis of metabolic and gene co-expression networks to explore how the soil microbiome responded to changes in soil moisture and nutrient conditions and to determine which genes were expressed under a given condition. Our integrated modeling approach revealed previously unknown, but critically important aspects of the soil microbiomes’ response to environmental perturbations. Incorporation of metabolomic and transcriptomic data into metabolic reaction networks identified condition-specific signature genes that are uniquely associated with dry, wet, and glycine-amended conditions. A subsequent gene co-expression network analysis revealed that drought-associated genes occupied more central positions in a network model of the soil community, compared to the genes associated with wet, and glycine-amended conditions. These results indicate the occurrence of system-wide metabolic coordination when soil microbiomes cope with moisture or nutrient perturbations. Importantly, the approach that we demonstrate here to analyze large-scale multi-omics data from a natural soil environment is applicable to other microbiome systems for which multi-omics data are available.

A study of Ki 67, p53 and their combination as immunomarkers in squamous cell carcinoma of oral cavity

Background: Oral cancer is the most common cancer and constitutes a major health problem. Tobacco and alcohol remains the most important etiologic factors. Molecular level changes in the lesion occur before clinical and histopathological changes. The prognostic evaluation of this neoplasia is given by histological and immunohistochemical findings, including staging, histological grade, tumor size, lymph node involvement, immunohistochemical expression of p53 and Ki-67.In squamous cell carcinomas of oral cavity, p53 and Ki-67 are related to large tumors, metastasis to lymph nodes and very likely to a worse prognosis. Aim and objectives: To assess and compare the expression p53, Ki-67 and their combination markers in squamous cell carcinoma of oral cavity in relation to lymph node status, degree of histological differentiation and pathological staging. Materials and Methods: The prospective study was conducted in N.I.M.S medical college carried out with 108 cases of oral cavity squamous cell carcinoma with lymph node resection. The p53 and Ki-67 labelling indices were expressed as the percentage of Ki-67 and p53 immunolabelled tumor nuclei per 1000 tumor nuclei counted. Results: The maximum numbers of cases were found to be in the age group of 40-60 years (61.8%), mostly being men (85.1%). Female comprised of only 14.9% of the patients. All cases were subjected to immunohistochemical study for Ki- 67 and p53. Positive expression of Ki 67 detected was in 92 cases and p53 was detected in 72 cases. Both Ki -67 and p53 were positive in 58 cases. Ki -67 marker was tested in all 108 cases. Out of total 108 cases 92 (85.2%) were found to be positive for Ki -67 and only 16(14.8%) were found negative. In the histological grading 48 (44.4%) were low grade (well differentiated), and 30 (55.6%), were high grade (moderately and poorly differentiated). Out of 48 low grade cases 14(29.2%) cases and out of 60 high grade cases 44(73.3%) were positive for p53and Ki 67 which was statist

Glass transition temperature of polybutadiene and polyisoprene from high temperature segmental relaxation correlation using molecular dynamics

ABSTRACT Predicting glass transition temperature for rubber and rubber composites is immensely important for tire industry for the development of products and fine-tune process conditions. Molecular dynamics simulation is been used to predict glass transition temperature as a function of molecular-level structural changes, e.g., composition (functional groups), topology, and polymerization. However, prediction of glass transition temperature within experimental error bar from molecular dynamics simulation is only possible from all atomistic description (model) of the system as united atom and coarse-grained models under-predict the values. Conventional way of calculation of glass transition temperature from density (or any other properties which show sharp transition)–temperature plots are computationally very demanding because of atomistic simulations and simulations below the glass transition point, i.e., in glassy state. Here we report a novel method for calculation of glass transition temperature using only segmental relaxation correlation functions calculated at higher temperatures, i.e., above glass transition temperature. We have presented a protocol here and shown for two polymeric systems polybutadiene and polyisoprene. We believe this method cuts the computational cost of predicting glass transition temperature by one-third and will be applicable for industrial applications for structure-property validations.

Multi-stress aging investigations of HTV silicone rubber filled with Silica/ATH composites for HVAC and HVDC transmission

Multi-stress aging performance of high-temperature-vulcanized-silicone rubber (HTV-SR) composites was investigated in a simulated environment separately both under AC and DC voltages. Two specially designed weathering chambers were fabricated one each for AC and DC voltages. Four type of SR-composites filled with varying amount of nano-silica and micro aluminum-tri-hydrate (ATH) were exposed to multi-stress aging spanning over a period of 5000 h. The test samples were designated as TS1, TS2, TS3 and TS4. The parameters of weather cycle were designed representing a prevailing local environment which is of great interest of operating electric utility company in the context of pollution severity. Different well-defined evaluation methods and diagnostic techniques were employed to understand aging behavior of each test samples. The surface wettability was evaluated using the Swedish Transmission Research Institute (STRI) classification method and through contact angle measurements. Leakage current was measured after each aging cycle to assess degree of surface aging. Fourier Transform Infrared (FTIR) spectroscopy was employed to identify and examine molecular-level changes in the material and a Scanning Electron Microscopy (SEM) was utilized to analyze the morphological changes in the HTV-SR. Mechanical properties of each sample were checked by measuring its tensile strength and elongation-at-break as well as through shore-A hardness tests. The study revealed that exposure to multi-stress aging caused de-polymerization, loss of hydrophobicity and material degradation of the test sample. The DC-stressed samples showed 20% to 30% higher degradation compared with their AC-stressed counterparts while other environmental stresses were maintained identical. This behavior is attributable to more detrimental effect of unidirectional DC stress. Having conducted overall assessment of aging, we found that among the various investigated samples, the TS2 exhibited maximum resistance to aging. These results are thoroughly presented in this paper.

Diagnosis of opioid use disorder with high sensitivity and specificity by advanced computational analysis of Fourier transform infrared spectroscopy

Opioid use disorder (OUD), which is a chronic disease and widespread public health problem results in death of the patient in the early period. The consumption of opioid depending on the use disorder time, affects blood biochemical parameters. OUD diagnosis can be clinically determined from biochemical values and with the screening tools in substance abuse. However, long-term OUD causes multiple pathological and physiological changes in many organs. Opioid initiated diseases, such as changes in tissue level and molecular level can be detected with advanced diagnostic methods after a long period of usage. It is important to diagnose these changes without causing organ dysfunction. The tests for the diagnose of chronic effects of OUD are expensive and time-consuming. In this study, we used Fourier transform infrared (FTIR) spectroscopy to discriminate the whole blood samples of opioid-addicted patients (n = 20) from healthy persons (n = 14) with an average addiction period of for 8 ± 5.8 years. We purposed to compare whole blood vibrational results of OUD and HC. In order to identify absorption bands on structures of proteins, lipids and nucleic acids, their corresponding absorbance of band spectra were measured. We had chosen following bands 2959, 2931, 1646, 1550, 1453, 1400, 1314, 1243, 1080, 1079, 1542, 1045, 1467 to identify peak heights and to compare peak height ratios such as H1646 to H1550, H1079 to H1542, H2959 to H2931, H1453 to H1400, H1314 to H1243, H1045 to H1467, H1080 to H1550. Statistically, the p value of group heights were significantly different (p < 0.001). As a chemometric method, features extracted by principal component analysis (PCA) and then classified by linear discriminate analysis (LDA) and support vector machine (SVM) to determine the spectral data of disorder zones. The confidence of specificity and sensitivity and accuracy were obtained as 93.33%, 85%, 80.57% in raw data, and 100%, 100% and 100% in the second derivative respectively. Our research illustrates that whole blood analyses by FTIR, on the selected peak heights may discriminate pathological and healthy structural changes induced long term opioid use disorder.Thus, we have demonstrated that infrared spectroscopy can provide a simple and available diagnostic test for OUD patients.

Cigarette smoke-induced changes in the murine vocal folds: a Raman spectroscopic observation.

Raman spectroscopic methods are being projected as novel tools to study the early invisible molecular level changes in a label-free manner. In the present study, we have used Raman spectroscopy to explore the earliest biochemical changes in murine vocal folds in response to time-bound cigarette smoke exposure. Mice were exposed to cigarette smoke for 2 or 4-weeks through a customized smoke inhalation system. The larynx was collected and initial evaluations using standard methods of analysis such as histopathology and immunofluorescence was performed. Concurrent unstained sections were used for Raman imaging. Two common pathological features of vocal fold disorders including alterations in collagen content and epithelial hypercellularity, or hyperplasia, were observed. The mean spectra, principal component analysis, and Raman mapping also revealed differences in the collagen content and hypercellularity in the smoke exposed tissues. The differences in 2-week exposed tissues were found to be more prominent as compared to 4-week. This was attributed to adaptive responses and the already reported biphasic effects, which suggest that collagen synthesis is significantly reduced at higher cigarette smoke concentrations. Overall findings of the study are supportive of the prospective application of Raman imaging in monitoring changes due to cigarette smoke in the vocal folds.

Role of X‐ray Scattering Techniques in Understanding the Collagen Structure of Leather

AbstractThis review focuses on the SAXS and WAXS analysis of the collagen structure of leather, from pioneering works through to recent developments. X‐ray scattering can be used to investigate the structural features of fibrillar collagen in the leather matrix, including axial periodicity, fibril diameter, chemical fixation, hydration and fibrillar orientation. Key properties of leather, such as appearance, handle, strength, hydrothermal stability and resistance to putrefaction, are closely linked to these parameters, thereby underlining the importance of X‐ray scattering to the study of leather. Recent research on the molecular level changes in collagen structure at different stages of leather processing with a range of treatments is also summarized. We will highlight how studies using X‐ray scattering techniques have provided significant insights into tanning processes which could be used to improve leather properties and optimize/reduce the use of tanning agents such as chromium (III) in the industry. The review will also describe the details of collagen structure and tanning mechanisms that are yet to be determined by X‐ray scattering, as well as future advancements of this technique and what it can accomplish for the leather industry.

The fitness challenge of studying molecular adaptation.

Advances in bioinformatics and high-throughput genetic analysis increasingly allow us to predict the genetic basis of adaptive traits. These predictions can be tested and confirmed, but the molecular-level changes - i.e. the molecular adaptation - that link genetic differences to organism fitness remain generally unknown. In recent years, a series of studies have started to unpick the mechanisms of adaptation at the molecular level. In particular, this work has examined how changes in protein function, activity, and regulation cause improved organismal fitness. Key to addressing molecular adaptations is identifying systems and designing experiments that integrate changes in the genome, protein chemistry (molecular phenotype), and fitness. Knowledge of the molecular changes underpinning adaptations allow new insight into the constraints on, and repeatability of adaptations, and of the basis of non-additive interactions between adaptive mutations. Here we critically discuss a series of studies that examine the molecular-level adaptations that connect genetic changes and fitness.

Artificial Neural Network Correlation and Biostatistics Evaluation of Physiological and Molecular Parameters in Healthy Young Individuals Performing Regular Exercise.

Studies support that regular physical activity (PA) decelerates senescence-related decline of physiological and molecular parameters in the elderly. We have addressed the other end of this spectrum: healthy and young, inactive individuals participated in a 6-month long personal trainer-guided lifestyle program. We have measured physiological and molecular parameters (differentiating high- and low responders) and their correlation with PA (sedentary status). Cluster analysis helped to distinguish individuals with high- or low PA and differentiate high- and low-responders of each parameter. The assessed cardiovascular parameters (heart rate, blood pressure, 6-min walking distance, relative VO2max), body composition parameters (body fat and muscle mass percentage) metabolic parameters (glucose, insulin, HDL, LDL), immune parameters (cortisol, CRP, lymphocyte counts, hTREC) all showed improvement. Artificial neural network analysis (ANN) showed correlation efficiencies of physiological and molecular parameters using a concept-free approach. ANN analysis appointed PA as the mastermind of molecular level changes. Besides sedentary status, insulin and hTREC showed significant segregation. Biostatistics evaluation also supported the schism of participants for their sedentary status, insulin concentration and hTREC copy number. In the future ANN and biostatistics, may predict individual responses to regular exercise. Our program reveals that high responder individuals of certain parameters may be low responders of others. Our data show that moderate regular PA is essential to counteract senescence in young and healthy individuals, despite individual differences in responsiveness. Such PA may not seem important in the everyday life of young and healthy adults, but shall become the base for healthy aging.

Occupational Heat Stress and DNA damage among steelworkers in Southern India

OPS 44: Occupational health studies with environmental implications, Room 411, Floor 4, August 27, 2019, 4:30 PM - 5:30 PM Background: Changing climatic scenario with rising temperatures will potentially subject millions of workers to risks of heat stress in tropical settings. Heat stress not only imposes a physiological strain on the exposed workers but also makes subcellular level changes including DNA damage in workers exposed to chronic high-heat environments. We explored the physiological and molecular level changes among such workers. Methodology: We used a cross-sectional study design and profiled the heat stress of about 1000 workers from 7 sectors viz., steel, garment, tire, brick, construction and agriculture and used a Quest Temp WBGT monitor to evaluate heat exposures and quantified heat strain indicators viz., Core Body Temperature, Sweat Rate and Urine Specific Gravity. We studied the DNA damage by enumerating the Micronuclei (MN) encountered in 120-steel industry workers exposed to chronic high-heat. Results: Heat stress was high in almost all the workplaces especially during summer months. Steel industry had the highest level of Wet Bulb Globe Temperature (WBGT) (Avg. 31.1±3.2°C) with ~90% workers having higher heat exposures above safe limits. A significant association was observed between the exposures to heat stress and heat strain (X2=4.45; p=0.035) and a significant increase in the MN-frequency was observed in exposed workers compared to the unexposed workers (X2=47.1; p<0.0001). The exposed workers had 23.3 times higher risk of DNA damage (OR=23.3; p<0.0001) compared to the unexposed workers even after adjusting for potential confounders. Years of exposure increased the risk of DNA damage (OR=15.5; p=<0.0001) and high-heat exposed workers had 81-times higher risk of DNA damage compared to the medium-heat exposed workers. Conclusion: Risks of exposures to chronic heat stress induces damages at a sub-cellular level. Further in-depth research studies are warranted and developing protective interventions to reduce exposure is imperative to avert health risks in the climate change scenario to protect millions of workers.

Hydrogen-Bonding in Liquid Water at Multikilobar Pressures.

High-precision THz (30 to 360 cm-1) spectra of bulk liquid water are presented from ambient conditions up to hydrostatic pressures of 10 kbar. In concert with ab initio simulations, this allows us to characterize the molecular-level changes of the H-bond network under solvent stress conditions. Both the experimental and theoretical THz spectra reveal a blue shift in the intermolecular translational mode at 180 cm-1 by 40 cm-1 at 10 kbar and a blue shift together with an intensity increase in the relaxation mode. These changes can be traced back to a pressure-induced increase of the population of so-called short H-bond double donor configurations at the expense of those with longer such intermolecular bonds. Distinct electronic polarization effects are critical to capture the characteristic intensity changes of the THz line shape function. These advances in high-pressure THz spectroscopy open the door to investigate the pressure response of solvation shells and solute-solvent couplings.

Proteomic analysis of chloroplasts from chlorophyll-deficient melon mutant

We aimed to understand the molecular-level changes occurring in the photosynthetic metabolic network in mutant chloro-plasts. We performed comparative liquid chromatography-mass spectrometry protein profiling of wild-type (WT) and chlorophyll-deficient melon (Cucumis melo L.) mutants. We identified 390 differentially expressed proteins and 81 shared proteins varied significantly in abundance, of which 76 were upregulated and 5 were downregulated. Differentially expressed proteins were involved in the following biological processes: binding, catalytic, structural, transporter, and antioxidant activities. The mutant had 6.08-fold higher expression of glutamate-1-semialdehyde 2,1-aminomutase (GSAM), an enzyme that synthesizes the chlorophyll precursor, 5-aminolevulinic acid, and a 5.02-fold higher expression of pyridoxal biosynthesis protein, a GSAM coenzyme. An RNA recognition motif-containing protein (RRM) decreased in expression by 5.22-fold. This suggests that GSAM and RRM are particularly relevant to chlorophyll deficiency.