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1.
iScience ; 27(5): 109723, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38706846

RESUMO

This study presents a machine learning (ML) framework aimed at accelerating the discovery of multi-property optimized Fe-Ni-Co alloys, addressing the time-consuming, expensive, and inefficient nature of traditional methods of material discovery, development, and deployment. We compiled a detailed heterogeneous database of the magnetic, electrical, and mechanical properties of Fe-Co-Ni alloys, employing a novel ML-based imputation strategy to address gaps in property data. Leveraging this comprehensive database, we developed predictive ML models using tree-based and neural network approaches for optimizing multiple properties simultaneously. An inverse design strategy, utilizing multi-objective Bayesian optimization (MOBO), enabled the identification of promising alloy compositions. This approach was experimentally validated using high-throughput methodology, highlighting alloys such as Fe66.8Co28Ni5.2 and Fe61.9Co22.8Ni15.3, which demonstrated superior properties. The predicted properties data closely matched experimental data within 14% accuracy. Our approach can be extended to a broad range of materials systems to predict novel materials with an optimized set of properties.

2.
Aging Dis ; 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38739943

RESUMO

Prior studies have emphasized a bioenergetic crisis in the retinal pigment epithelium (RPE) as a critical factor in the development of age-related macular degeneration (AMD). The isoforms Fructose-1,6-bisphosphate aldolase C (ALDOC) and pyruvate kinase M2 (PKM2) have been proposed to play a role in AMD pathogenesis. While PKM2 and ALDOC are crucial for aerobic glycolysis in the neural retina, they are not as essential for the RPE. In this study, we examined the expression and activity of PKM2 and ALDOC in both young and aged RPE cells, as well as in the retina and RPE tissue of mice, including an experimentally induced AMD mouse model. Our findings reveal an upregulation in PKM2 and ALDOC expression, accompanied by increased pyruvate kinase activity, in the aged and AMD mouse RPE. Conversely, there is a decrease in ALDOC expression but an increase in PKM2 expression and pyruvate kinase activity in the aged and AMD retina. Overall, our study indicates that aged and AMD RPE cells tend to favor aerobic glycolysis, while this tendency is diminished in the aged and AMD retina. These results underscore the significance of targeting PKM2 and ALDOC in the RPE as a promising therapeutic approach to address the bioenergetic crisis and prevent vision loss in AMD.

3.
Aging Dis ; 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38300646

RESUMO

Insulin-like growth factor-1 (IGF-1) plays a diverse role in the retina, exerting its effects in both normal and diseased conditions. Deficiency of IGF-1 in humans leads to issues such as microcephaly, mental retardation, deafness, and postnatal growth failure. IGF-1 is produced in the retinal pigment epithelium (RPE) and activates the IGF-1 receptor (IGF-1R) in photoreceptor cells. When IGF-1R is absent in rod cells, it results in the degeneration of photoreceptors, emphasizing the neuroprotective function of IGF signaling in these cells. Contrastingly, in neovascular age-related macular degeneration (AMD), there is an overexpression of both IGF-1 and IGF-1R in RPE. The mechanisms behind this altered regulation of IGF-1 in diseased states are currently unknown. This comprehensive review provides recent insights into the role of IGF-1 in the health and disease of the retina, raising several unanswered questions that still need further investigation.

4.
Cureus ; 15(7): e41928, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37583732

RESUMO

Behcet's disease (BD) is a chronic systemic inflammatory vasculitis with a relapsing and remitting course. The disease predominantly affects males between the ages of 20 and 40 years. The disease is more prevalent in Middle Eastern and Asian countries but is less common in North American countries. BD typically presents as recurrent oro-genital ulcers and ocular inflammation. Pulmonary vasculitis with pulmonary arterial involvement is a unique manifestation, with most pulmonary manifestations occurring later in the disease course. Here, we report a case with pulmonary arterial aneurysms and variable arterial-venous thrombosis in a young African American Male diagnosed with BD after he presented with pulmonary manifestations. This report emphasizes that a high index of suspicion is needed to diagnose a rare condition with such variable manifestations as Behcet's disease and that early detection and immunosuppression therapy can confer improved prognosis.

5.
Nat Commun ; 14(1): 4811, 2023 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-37558655

RESUMO

Low grade waste heat accounts for ~65% of total waste heat, but conventional waste heat recovery technology exhibits low conversion efficiency for low grade waste heat recovery. Hence, we designed a thermomagnetic generator for such applications. Unlike its usual role as the coil core or big magnetic yoke in previous works, here the magnetocaloric material acts as a switch that controls the magnetic circuit. This makes it not only have the advantage of flux reversal of the pretzel-like topology, but also present a simpler design, lower magnetic stray field, and higher performance by using less magnetocaloric material than preceding devices. The effects of key structural and system parameters were studied through a combination of experiments and finite element simulations. The optimized max power density PDmax produced by our device is significantly higher than those of other existing active thermomagnetic, thermo, and pyroelectric generators. Such high performance shows the effectiveness of our topology design of magnetic circuit with magnetocaloric switch.

6.
PNAS Nexus ; 2(3): pgad063, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37007713

RESUMO

Phosphoinositides (PIPs) are a family of minor acidic phospholipids in the cell membrane. Phosphoinositide (PI) kinases and phosphatases can rapidly convert one PIP product into another resulting in the generation of seven distinct PIPs. The retina is a heterogeneous tissue composed of several cell types. In the mammalian genome, around 50 genes encode PI kinases and PI phosphatases; however, there are no studies describing the distribution of these enzymes in the various retinal cell types. Using translating ribosome affinity purification, we have identified the in vivo distribution of PI-converting enzymes from the rod, cone, retinal pigment epithelium (RPE), Müller glia, and retinal ganglion cells, generating a physiological atlas for PI-converting enzyme expression in the retina. The retinal neurons, rods, cones, and RGCs, are characterized by the enrichment of PI-converting enzymes, whereas the Müller glia and RPE are characterized by the depletion of these enzymes. We also found distinct differences between the expression of PI kinases and PI phosphatases in each retinal cell type. Since mutations in PI-converting enzymes are linked to human diseases including retinal diseases, the results of this study will provide a guide for what cell types are likely to be affected by retinal degenerative diseases brought on by changes in PI metabolism.

7.
PNAS Nexus ; 2(3): pgad038, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36896135

RESUMO

The postmitotic retina is highly metabolic and the photoreceptors depend on aerobic glycolysis for an energy source and cellular anabolic activities. Lactate dehydrogenase A (LDHA) is a key enzyme in aerobic glycolysis, which converts pyruvate to lactate. Here we show that cell-type-specific actively translating mRNA purification by translating ribosome affinity purification shows a predominant expression of LDHA in rods and cones and LDHB in the retinal pigment epithelium and Müller cells. We show that genetic ablation of LDHA in the retina resulted in diminished visual function, loss of structure, and a loss of dorsal-ventral patterning of the cone-opsin gradient. Loss of LDHA in the retina resulted in increased glucose availability, promoted oxidative phosphorylation, and upregulated the expression of glutamine synthetase (GS), a neuron survival factor. However, lacking LDHA in Müller cells does not affect visual function in mice. Glucose shortage is associated with retinal diseases, such as age-related macular degeneration (AMD), and regulating the levels of LDHA may have therapeutic relevance. These data demonstrate the unique and unexplored roles of LDHA in the maintenance of a healthy retina.

8.
J Neonatal Perinatal Med ; 16(1): 33-37, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36591661

RESUMO

OBJECTIVE: To evaluate the implementation of a systematic approach to improve the resuscitation, stabilization, and admission of infants < 32 weeks gestation and also to ascertain its effect on organization, efficiency, and clinical outcomes during hospitalization. METHODS: Retrospective study involving a multidisciplinary team with checklists, role assignment, equipment organization, step by step protocol, and real time documentation for the care of infants < 32 weeks gestation in the delivery room to the neonatal intensive care unit. Pre-data collection (cases) period was from Aug, 2015 to July, 2017, and post-data collection(controls) period was from Aug, 2017 to Aug, 2019. RESULTS: 337 infants were included (179 cases; 158 controls). Increase surfactant use in the resuscitation room (41% vs. 27%, p = 0.007) and reduction in median time to administer surfactant (34 minutes (range, 6-120) vs. 74 minutes (range, 7-120), p = 0.001) observed in control-group. There was a significant reduction in incidence of bronchopulmonary dysplasia (27% vs. 39%), intraventricular hemorrhage (11% vs. 17%), severe retinopathy of prematurity (3% vs. 9%), and necrotizing enterocolitis (4% vs. 6%), however these results were not statistically significant after controlling for severity of illness. CONCLUSIONS: A systematic approach to the care of infants < 32 weeks gestation significantly improved mortality rates and reduced rates of comorbidities.


Assuntos
Displasia Broncopulmonar , Doenças do Recém-Nascido , Gravidez , Recém-Nascido , Humanos , Lactente , Feminino , Idade Gestacional , Estudos Retrospectivos , Salas de Parto , Recém-Nascido Prematuro , Displasia Broncopulmonar/epidemiologia , Hospitalização
9.
RSC Adv ; 12(50): 32652-32658, 2022 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-36425718

RESUMO

A pillared-layer MOF, {[Cu2(Fu)2(BPY)]·H2O} n , was synthesized at room temperature employing a mixture of water and methanol as the reaction solvent. By using the sodium salts of fumarate, instead of the native acids, the target MOF could be readily prepared in aqueous media. The PXRD of this MOF was found to be in good agreement with the simulated diffractogram from single crystal data of related MOF made at a higher temperature using DMF as the solvent. In addition to characterization by PXRD, TGA, and ESEM, N2-sorption measurements revealed the formation of mesopores in the MOF's structure under study. The electronic band gap and magnetic properties of this pillared-layer MOF were also studied.

10.
Phys Biol ; 19(5)2022 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-35790172

RESUMO

There have been a number of pharmaceutical and non-pharmaceutical interventions associated with COVID-19 over the past two years. Various non-pharmaceutical interventions were proposed and implemented to control the spread of the COVID-19 pandemic. Most common of these were partial and complete lockdowns that were used in an attempt to minimize the costs associated with mortality, economic losses and social factors, while being subject to constraints such as finite hospital capacity. Here, we use a minimal model posed in terms of optimal control theory to understand the costs and benefits of such strategies. This allows us to determine top-down policies for how to restrict social contact rates given an age-structured model for the dynamics of the disease. Depending on the relative weights allocated to mortality and socioeconomic losses, we see that the optimal strategies range from long-term social-distancing only for the most vulnerable, partial lockdown to ensure not over-running hospitals, and alternating-shifts, all of which lead to significant reduction in mortality and/or socioeconomic losses. Crucially, commonly used strategies that involve long periods of broad lockdown are almost never optimal, as they are highly unstable to reopening and entail high socioeconomic costs. Using parameter estimates from data available for Germany and the USA early in the pandemic, we quantify these policies and use sensitivity analysis in the relevant model parameters and initial conditions to determine the range of robustness of our policies. Finally we also discuss how bottom-up behavioral changes affect the dynamics of the pandemic and show how they can work in tandem with top-down control policies to mitigate pandemic costs even more effectively.


Assuntos
COVID-19 , Pandemias , COVID-19/epidemiologia , COVID-19/prevenção & controle , Controle de Doenças Transmissíveis , Humanos , Pandemias/prevenção & controle , Políticas
11.
Cell Death Dis ; 13(7): 613, 2022 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-35840554

RESUMO

Insulin-like growth factor I (IGF-1) is a neurotrophic factor and is the ligand for insulin-like growth factor 1 receptor (IGF-1R). Reduced expression of IGF-1 has been reported to cause deafness, mental retardation, postnatal growth failure, and microcephaly. IGF-1R is expressed in the retina and photoreceptor neurons; however, its functional role is not known. Global IGF-1 KO mice have age-related vision loss. We determined that conditional deletion of IGF-1R in photoreceptors and pan-retinal cells produces age-related visual function loss and retinal degeneration. Retinal pigment epithelial cell-secreted IGF-1 may be a source for IGF-1R activation in the retina. Altered retinal, fatty acid, and phosphoinositide metabolism are observed in photoreceptor and retinal cells lacking IGF-1R. Our results suggest that the IGF-1R pathway is indispensable for photoreceptor survival, and activation of IGF-1R may be an essential element of photoreceptor and retinal neuroprotection.


Assuntos
Fator de Crescimento Insulin-Like I , Células Fotorreceptoras de Vertebrados , Degeneração Retiniana , Animais , Fator de Crescimento Insulin-Like I/genética , Fator de Crescimento Insulin-Like I/metabolismo , Camundongos , Neurônios/metabolismo , Neuroproteção/genética , Neuroproteção/fisiologia , Células Fotorreceptoras de Vertebrados/metabolismo , Receptor IGF Tipo 1/genética , Receptor IGF Tipo 1/metabolismo , Retina/metabolismo , Degeneração Retiniana/genética , Degeneração Retiniana/metabolismo
12.
J Biol Chem ; 298(6): 101944, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35447116

RESUMO

Mechanistic target of rapamycin (mTOR) and mTOR complex 1 (mTORC1), linchpins of the nutrient sensing and protein synthesis pathways, are present at relatively high levels in the ganglion cell layer (GCL) and retinal ganglion cells (RGCs) of rodent and human retinas. However, the role of mTORCs in the control of protein synthesis in RGC is unknown. Here, we applied the SUrface SEnsing of Translation (SUnSET) method of nascent protein labeling to localize and quantify protein synthesis in the retinas of adult mice. We also used intravitreal injection of an adeno-associated virus 2 vector encoding Cre recombinase in the eyes of mtor- or rptor-floxed mice to conditionally knockout either both mTORCs or only mTORC1, respectively, in cells within the GCL. A novel vector encoding an inactive Cre mutant (CreΔC) served as control. We found that retinal protein synthesis was highest in the GCL, particularly in RGC. Negation of both complexes or only mTORC1 significantly reduced protein synthesis in RGC. In addition, loss of mTORC1 function caused a significant reduction in the pan-RGC marker, RNA-binding protein with multiple splicing, with little decrease of the total number of cells in the RGC layer, even at 25 weeks after adeno-associated virus-Cre injection. These findings reveal that mTORC1 signaling is necessary for maintaining the high rate of protein synthesis in RGCs of adult rodents, but it may not be essential to maintain RGC viability. These findings may also be relevant to understanding the pathophysiology of RGC disorders, including glaucoma, diabetic retinopathy, and optic neuropathies.


Assuntos
Glaucoma , Células Ganglionares da Retina , Animais , Glaucoma/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Camundongos , Retina/metabolismo , Células Ganglionares da Retina/metabolismo
13.
iScience ; 25(4): 104047, 2022 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-35359811

RESUMO

Magnetic high-entropy alloys (HEAs) are a new category of high-performance magnetic materials, with multicomponent concentrated compositions and complex multi-phase structures. Although there have been numerous reports of their interesting magnetic properties, there is very limited understanding about the interplay between their hierarchical multi-phase structures and the resulting magnetic behavior. We reveal for the first time the influence of a hierarchically decomposed B2 + A2 structure in an AlCo0.5Cr0.5FeNi HEA on the formation of magnetic vortex states within individual A2 (disordered BCC) precipitates, which are distributed in an ordered B2 matrix that is weakly ferromagnetic. Non-magnetic or weakly ferromagnetic B2 precipitates in large magnetic domains of the A2 phase, and strongly magnetic Fe-Co-rich interphase A2 regions, are also observed. These results provide important insight into the origin of coercivity in this HEA, which can be attributed to a complex magnetization process that includes the successive reversal of magnetic vortices.

14.
Artigo em Inglês | MEDLINE | ID: mdl-35427794

RESUMO

Reversible phosphorylation of phosphatidylinositol by phosphoinositide (PI) kinases and phosphatases generates seven distinct phosphoinositide phosphates, called phosphoinositides or PIPs. All seven PIPs are formed in the retina and photoreceptor cells. Around 50 genes in the mammalian genome encode PI kinases and PI phosphatases. There are no studies available on the distribution of these enzymes in the retina and photoreceptors. AIM: To employ Ribosomal Targeting Strategy and Nuclear Labeling to Analyze Phosphoinositide Signatures in rod-photoreceptor cells. METHODS: HA-tagging of ribosomal protein Rpl22 was induced with Cre-recombinase under the control of the rhodopsin promoter. Actively translating mRNAs associated with polyribosomes were isolated by immunoprecipitation with HA antibody, followed by RNA isolation and gene identification. We also isolated biotinylated-rod nuclei from NuTRAP mice under the control of the rhodopsin-Cre promoter and analyzed nuclear phosphoinositides. RESULTS: Our results indicate that the expression of class I and class III PI 3-kinase, PI4K IIIß, PI 5-kinase, PIKfyve, PI3-phosphatases, MTMR2, 4, 6, 7, 14, PI4-phosphatase, TMEM55A, PI 5-phosphatases, SYNJI, INPP5B, INPP5E, INPP5F, SKIP and other phosphatases with dual substrate specificity, PTPMT1, SCAM1, and FIG4 are highly enriched in rod photoreceptor cells compared with the retina and cone-like retina. Our analysis identified the presence of PI(4)P, PI(3,4)P2, PI(3,5)P2, and PI(4,5)P2 in the rod nuclei. CONCLUSIONS: Our studies for the first time demonstrate the expression of PI kinases, PI phosphatases, and nuclear PIPs in rod photoreceptor cells. The NuTRAP mice may be useful not only for epigenetic and transcriptomic studies but also for in vivo cell-specific lipidomics research.


Assuntos
Monoéster Fosfórico Hidrolases , Células Fotorreceptoras , Ribossomos , 1-Fosfatidilinositol 4-Quinase , Animais , Flavoproteínas , Camundongos , Fosfatidilinositol 3-Quinases/metabolismo , Fosfatos de Fosfatidilinositol/metabolismo , Fosfatases de Fosfoinositídeos , Monoéster Fosfórico Hidrolases/genética , Monoéster Fosfórico Hidrolases/metabolismo , Células Fotorreceptoras/metabolismo , Proteínas Tirosina Fosfatases não Receptoras , Rodopsina
17.
Anal Methods ; 13(33): 3705-3723, 2021 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-34338254

RESUMO

The current study presents a specific, accurate, simple, and rapid UPLC method for the determination of impurities present in cream and ointment formulations of betamethasone dipropionate (BMD). The analytical method was optimized using central composite design (CCD) prior to the method validation. Critical Process Parameters (CPPs) and Critical Quality Attributes (CQAs) were identified for the analytical method. A total of 17 experiments were carried out and verified the individual and interaction effects of CPPs. The CPPs were optimized using a numerical method by keeping the CQAs within the desired range (R1-R2: minimize & R3-R5: maximize) as an optimization goal. Optimized chromatographic separation was achieved using a Waters Acquity UPLC BEH C18, 100 mm × 2.1 mm, 1.7 µm column with a gradient mode of elution comprising 20 mM phosphate buffer: ACN 70 : 30, v/v as mobile phase-A and 20 mM phosphate buffer: ACN 30 : 70, v/v as mobile phase-B. The developed method was validated in accordance with ICH guidelines. The validation data conclude that the developed method is specific, accurate, linear, precise, rugged, and robust for the quantification of impurities in BMD topical formulations.


Assuntos
Betametasona , Betametasona/análogos & derivados , Cromatografia Líquida de Alta Pressão , Limite de Detecção , Reprodutibilidade dos Testes
18.
BMC Microbiol ; 21(1): 225, 2021 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-34362295

RESUMO

BACKGROUND: Necrotising enterocolitis (NEC) is a devastating bowel disease, primarily affecting premature infants, with a poorly understood aetiology. Prior studies have found associations in different cases with an overabundance of particular elements of the faecal microbiota (in particular Enterobacteriaceae or Clostridium perfringens), but there has been no explanation for the different results found in different cohorts. Immunological studies have indicated that stimulation of the TLR4 receptor is involved in development of NEC, with TLR4 signalling being antagonised by the activated TLR9 receptor. We speculated that differential stimulation of these two components of the signalling pathway by different microbiota might explain the dichotomous findings of microbiota-centered NEC studies. Here we used shotgun metagenomic sequencing and qPCR to characterise the faecal microbiota community of infants prior to NEC onset and in a set of matched controls. Bayesian regression was used to segregate cases from control samples using both microbial and clinical data. RESULTS: We found that the infants suffering from NEC fell into two groups based on their microbiota; one with low levels of CpG DNA in bacterial genomes and the other with high abundances of organisms expressing LPS. The identification of these characteristic communities was reproduced using an external metagenomic validation dataset. We propose that these two patterns represent the stimulation of a common pathway at extremes; the LPS-enriched microbiome suggesting overstimulation of TLR4, whilst a microbial community with low levels of CpG DNA suggests reduction of the counterbalance to TLR4 overstimulation. CONCLUSIONS: The identified microbial community patterns support the concept of NEC resulting from TLR-mediated pathways. Identification of these signals suggests characteristics of the gastrointestinal microbial community to be avoided to prevent NEC. Potential pre- or pro-biotic treatments may be designed to optimise TLR signalling.


Assuntos
Enterocolite Necrosante/microbiologia , Células Epiteliais/imunologia , Microbioma Gastrointestinal/genética , Doenças do Prematuro/microbiologia , Receptor 4 Toll-Like/imunologia , Teorema de Bayes , DNA Bacteriano/genética , Enterocolite Necrosante/imunologia , Células Epiteliais/microbiologia , Fezes/microbiologia , Humanos , Lactente , Recém-Nascido , Recém-Nascido Prematuro , Doenças do Prematuro/imunologia , Metagenômica , RNA Ribossômico 16S/genética , Receptor 4 Toll-Like/genética
19.
Commun Biol ; 4(1): 850, 2021 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-34239035

RESUMO

The retinal pigmented epithelium (RPE) is a monolayer of multifunctional cells located at the back of the eye. High membrane turnover and polarization, including formation of actin-based apical microvilli, are essential for RPE function and retinal health. Herein, we demonstrate an important role for ßA3/A1-crystallin in RPE. ßA3/A1-crystallin deficiency leads to clathrin-mediated epidermal growth factor receptor (EGFR) endocytosis abnormalities and actin network disruption at the apical side that result in RPE polarity disruption and degeneration. We found that ßA3/A1-crystallin binds to phosphatidylinositol transfer protein (PITPß) and that ßA3/A1-crystallin deficiency diminishes phosphatidylinositol 4,5-biphosphate (PI(4,5)P2), thus probably decreasing ezrin phosphorylation, EGFR activation, internalization, and degradation. We propose that ßA3/A1-crystallin acquired its RPE function before evolving as a structural element in the lens, and that in the RPE, it modulates the PI(4,5)P2 pool through PITPß/PLC signaling axis, coordinates EGFR activation, regulates ezrin phosphorylation and ultimately the cell polarity.


Assuntos
Polaridade Celular/fisiologia , Endocitose , Células Epiteliais/metabolismo , Receptores ErbB/metabolismo , Epitélio Pigmentado da Retina/metabolismo , Cadeia A de beta-Cristalina/metabolismo , Animais , Polaridade Celular/genética , Proteínas do Citoesqueleto/metabolismo , Células Epiteliais/ultraestrutura , Humanos , Camundongos Knockout , Fosfatidilinositol 4,5-Difosfato/metabolismo , Proteínas de Transferência de Fosfolipídeos/metabolismo , Fosforilação , Ligação Proteica , Epitélio Pigmentado da Retina/citologia , Cadeia A de beta-Cristalina/genética
20.
Methods Mol Biol ; 2306: 227-238, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33954950

RESUMO

This book chapter provides readers the step-by-step instruction for cell growth, lipid isolation, and lipid analysis to obtain the lipidome of Corynebacterium glutamicum (C. glutamicum) in the genus Corynebacterium, a biotechnologically important bacterium. We separate the lipid families by preparative HPLC with an analytical C-8 column, followed by linear ion-trap multiple stage mass spectrometry (LIT MSn) with high-resolution mass measurement to define the structures of cytidine diphosphate diacylglycerol (CDP-DAG), glucuronosyl diacylglycerol (GlcA-DAG), α-D-mannopyranosyl-(1 â†’ 4)-α-D-glucuronyl diacylglycerol (Man-GlcA-DAG), 1-mycolyl-2-acyl-phosphatidylglycerol (MA-PG), and acyl trehalose monomycolate (acyl-TMM) whose structures have been previously mis-assigned or not defined by mass spectrometric means. We also define the structures of mycolic acid, phosphatidylglycerol, phosphatidylinositol, cardiolipin, trehalose dimycolate lipids in the cell wall. The similarity of the lipidome to that in the Mycobacterium genera is consistent with the notion that Corynebacterium and Mycobacterium are gram-positive bacteria belonging to the suborder Corynebacterineae.


Assuntos
Corynebacterium glutamicum/crescimento & desenvolvimento , Lipidômica/métodos , Lipídeos/análise , Técnicas Bacteriológicas , Cromatografia Líquida de Alta Pressão , Corynebacterium glutamicum/química , Estrutura Molecular , Espectrometria de Massas por Ionização por Electrospray
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