Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 37.166
Filter
1.
Mol Cell ; 84(9): 1802-1810.e4, 2024 May 02.
Article in English | MEDLINE | ID: mdl-38701741

ABSTRACT

Polyphosphate (polyP) is a chain of inorganic phosphate that is present in all domains of life and affects diverse cellular phenomena, ranging from blood clotting to cancer. A study by Azevedo et al. described a protein modification whereby polyP is attached to lysine residues within polyacidic serine and lysine (PASK) motifs via what the authors claimed to be covalent phosphoramidate bonding. This was based largely on the remarkable ability of the modification to survive extreme denaturing conditions. Our study demonstrates that lysine polyphosphorylation is non-covalent, based on its sensitivity to ionic strength and lysine protonation and absence of phosphoramidate bond formation, as analyzed via 31P NMR. Ionic interaction with lysine residues alone is sufficient for polyP modification, and we present a new list of non-PASK lysine repeat proteins that undergo polyP modification. This work clarifies the biochemistry of polyP-lysine modification, with important implications for both studying and modulating this phenomenon. This Matters Arising paper is in response to Azevedo et al. (2015), published in Molecular Cell. See also the Matters Arising Response by Azevedo et al. (2024), published in this issue.


Subject(s)
Amides , Lysine , Phosphoric Acids , Polyphosphates , Lysine/metabolism , Lysine/chemistry , Polyphosphates/chemistry , Polyphosphates/metabolism , Phosphorylation , Humans , Protein Processing, Post-Translational , Proteins/chemistry , Proteins/metabolism , Proteins/genetics
2.
Mol Cell ; 84(9): 1811-1815.e3, 2024 May 02.
Article in English | MEDLINE | ID: mdl-38701742

ABSTRACT

Post-translational modifications of proteins (PTMs) introduce an extra layer of complexity to cellular regulation. Although phosphorylation of serine, threonine, and tyrosine residues is well-known as PTMs, lysine is, in fact, the most heavily modified amino acid, with over 30 types of PTMs on lysine having been characterized. One of the most recently discovered PTMs on lysine residues is polyphosphorylation, which sees linear chains of inorganic polyphosphates (polyP) attached to lysine residues. The labile nature of phosphoramidate bonds raises the question of whether this modification is covalent in nature. Here, we used buffers with very high ionic strength, which would disrupt any non-covalent interactions, and confirmed that lysine polyphosphorylation occurs covalently on proteins containing PASK domains (polyacidic, serine-, and lysine-rich), such as the budding yeast protein nuclear signal recognition 1 (Nsr1) and the mammalian protein nucleolin. This Matters Arising Response paper addresses the Neville et al. (2024) Matters Arising paper, published concurrently in Molecular Cell.


Subject(s)
Lysine , Phosphoproteins , Protein Processing, Post-Translational , RNA-Binding Proteins , Phosphorylation , Lysine/metabolism , Phosphoproteins/metabolism , Phosphoproteins/chemistry , Phosphoproteins/genetics , Humans , RNA-Binding Proteins/metabolism , RNA-Binding Proteins/genetics , RNA-Binding Proteins/chemistry , Nucleolin , Saccharomyces cerevisiae Proteins/metabolism , Saccharomyces cerevisiae Proteins/genetics , Saccharomyces cerevisiae Proteins/chemistry , Animals , Saccharomyces cerevisiae/metabolism , Saccharomyces cerevisiae/genetics , Polyphosphates/metabolism , Polyphosphates/chemistry , Osmolar Concentration
3.
Microb Cell Fact ; 23(1): 132, 2024 May 06.
Article in English | MEDLINE | ID: mdl-38711050

ABSTRACT

BACKGROUND: 1,5-pentanediol (1,5-PDO) is a linear diol with an odd number of methylene groups, which is an important raw material for polyurethane production. In recent years, the chemical methods have been predominantly employed for synthesizing 1,5-PDO. However, with the increasing emphasis on environmentally friendly production, it has been a growing interest in the biosynthesis of 1,5-PDO. Due to the limited availability of only three reported feasible biosynthesis pathways, we developed a new biosynthetic pathway to form a cell factory in Escherichia coli to produce 1,5-PDO. RESULTS: In this study, we reported an artificial pathway for the synthesis of 1,5-PDO from lysine with an integrated cofactor and co-substrate recycling and also evaluated its feasibility in E.coli. To get through the pathway, we first screened aminotransferases originated from different organisms to identify the enzyme that could successfully transfer two amines from cadaverine, and thus GabT from E. coli was characterized. It was then cascaded with lysine decarboxylase and alcohol dehydrogenase from E. coli to achieve the whole-cell production of 1,5-PDO from lysine. To improve the whole-cell activity for 1,5-PDO production, we employed a protein scaffold of EutM for GabT assembly and glutamate dehydrogenase was also validated for the recycling of NADPH and α-ketoglutaric acid (α-KG). After optimizing the cultivation and bioconversion conditions, the titer of 1,5-PDO reached 4.03 mM. CONCLUSION: We established a novel pathway for 1,5-PDO production through two consecutive transamination reaction from cadaverine, and also integrated cofactor and co-substrate recycling system, which provided an alternative option for the biosynthesis of 1,5-PDO.


Subject(s)
Biosynthetic Pathways , Escherichia coli , Escherichia coli/metabolism , Escherichia coli/genetics , Metabolic Engineering/methods , Glycols/metabolism , Lysine/metabolism , Lysine/biosynthesis , Alcohol Dehydrogenase/metabolism , Transaminases/metabolism , Transaminases/genetics , Carboxy-Lyases/metabolism
4.
Food Res Int ; 186: 114397, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38729739

ABSTRACT

The formation mechanism behind the sophisticated aromas of sesame oil (SO) has not been elucidated. The interaction effects of the Maillard reaction (MR) and lipid oxidation on the aroma formation of fragrant sesame oil were investigated in model reaction systems made of l-lysine (Lys) and d-glucose (Glc) with or without fresh SO (FSO) or oxidized SO (OSO). The addition of OSO to the Lys-Glc model increased the MR browning at 294 nm and 420 nm and enhanced the DPPH radical scavenging activity greater than the addition of FSO (p < 0.05). The presence of lysine and glucose inhibited the oxidation of sesame oil, reduced the loss of γ-tocopherol, and facilitated the formation of sesamol (p < 0.05). The Maillard-lipid interaction led to the increased concentrations of some of the alkylpyrazines, alkylfurans, and MR-derived ketones and acids (p < 0.05) while reducing the concentrations of other pyrazines, lipid-derived furans, aliphatic aldehydes, ketones, alcohols, and acids (p < 0.05). The addition of FSO to the MR model enhanced the characteristic roasted, nutty, sweet, and fatty aromas in sesame oil (p < 0.05), while excessive lipid oxidation (OSO) brought about an unpleasant oxidized odor and reduced the characteristic aromas. This study helps to understand the sophisticated aroma formation mechanism in sesame oil and provides scientific instruction for precise flavor control in the production of sesame oil.


Subject(s)
Glucose , Lysine , Maillard Reaction , Odorants , Oxidation-Reduction , Sesame Oil , Sesame Oil/chemistry , Glucose/chemistry , Odorants/analysis , Lysine/chemistry , Phenols/chemistry , Benzodioxoles
5.
Chirality ; 36(5): e23670, 2024 May.
Article in English | MEDLINE | ID: mdl-38716587

ABSTRACT

Metal clusters have drawn considerable research attention over the years due to their fascinating optical properties. Owing to their appealing photophysical characteristics, these materials have drawn attention as potential candidates for various application in diverse fields, including disease detection, biosensing, chemical sensing, and the fabrication of light-harvesting materials. Presently, there is an increasing research focus on the use of clusters in biomedical research, both as biodetection platform and as bioimaging agents. Of special interest are chiral clusters, which can selectively interact with chiral biomolecules owing to their optical activity. Herein, we showcase the use of a pair of chiroptically active copper clusters for the enantioselective detection of lysine, an amino acid of vast biological relevance. Two techniques are concurrently employed for the detection of lysine at varying concentrations. Circular dichroism serves as a potent tool for detecting lysine at low concentrations, whereas luminescence is effectively employed as a detection method for high analyte concentrations. The combined electronic impact of clusters and lysine resulted in the emergence of an enhanced enantioselective Cotton effect at specific wavelength.


Subject(s)
Copper , Lysine , Lysine/chemistry , Lysine/analysis , Copper/chemistry , Copper/analysis , Stereoisomerism , Circular Dichroism/methods
6.
Front Endocrinol (Lausanne) ; 15: 1371220, 2024.
Article in English | MEDLINE | ID: mdl-38737551

ABSTRACT

Background and objective: Aberrant epigenetic regulation and increased oxidative stress in the placenta play a significant role in placental pathophysiology and fetal programming in preeclampsia, a hypertensive disorder in human pregnancy. The purpose of the study is to investigate if hypermethylation of histone H3K9 occurs in placental trophoblasts from preeclampsia. Methods: Trophoblasts were isolated and cultured from 14 placentas, 7 from normotensive pregnant women and 7 from preeclamptic pregnancies. Methylated H3K9 expression and antioxidant superoxide dismutase expression were determined by Western blot. We also examined consequences of oxidative stress and the downstream effects of histone methyltransferase inhibition on H3K9 expression associated with antioxidant CuZn-SOD and Mn-SOD expression in placental trophoblasts. Results: We found that expression of mono-, di-, and tri-methylation of histone H3 lysine 9 (H3K9me1, H3K9me2 and H3K9me3) was significantly increased, p<0.01, which correlated with downregulation of antioxidant superoxide dismutase CuZn-SOD and Mn-SOD expression, in trophoblasts from preeclamptic placentas compared to those from uncomplicated control placentas. We further demonstrated hypoxia could promote histone H3K9 methylation in placental trophoblasts, and hypoxia-induced upregulation of H3K9me1, H3K9me2 and H3K9me3 expression was reversible when hypoxic condition was removed. In addition, we also uncovered that inhibition of methyltransferase not only prevented hypoxia-induced upregulation of H3K9me1, H3K9me2 and H3K9me3 expression, but also abolished hypoxia-induced downregulation of CuZn-SOD and Mn-SOD expression in placental trophoblasts. Conclusions: These findings are noteworthy and provide further evidence that increased oxidative stress in the intrauterine environment is likely a mechanism to induce aberrant histone modification in placental trophoblasts in preeclampsia. Moreover, CuZn-SOD and Mn-SOD expression/activity are possibly H3K9 methylation-dependent in placental trophoblasts, which further suggest that oxidative stress and aberrant histone modification have significant impact on placental trophoblasts/fetal programming in preeclampsia.


Subject(s)
Histones , Oxidative Stress , Placenta , Pre-Eclampsia , Trophoblasts , Humans , Female , Pre-Eclampsia/metabolism , Pre-Eclampsia/genetics , Pre-Eclampsia/pathology , Pregnancy , Trophoblasts/metabolism , Histones/metabolism , Adult , Placenta/metabolism , Methylation , Superoxide Dismutase/metabolism , Superoxide Dismutase/genetics , DNA Methylation , Cells, Cultured , Lysine/metabolism
7.
J Clin Pediatr Dent ; 48(3): 131-138, 2024 May.
Article in English | MEDLINE | ID: mdl-38755991

ABSTRACT

In the current odontological era, carious lesions are removed while tooth tissue is preserved. Most of these ideals are met by chemomechanical caries removal (CMCR) methods, which are easy and comfortable to use, differentiate and eliminate infected tissues, minimize pressure, vibration and heat, and are cost-effective. This study examines the efficacy of commercially available CMCR agents, namely Papacarie®, Carie-Care™ and BRIX3000™, and a conventional hand instrumentation method for caries removal in deciduous molars in terms of time consumption, ease of application, and pain perception. For this randomized clinical trial, 120 children aged 4 to 9 years were selected and randomly allocated to four groups of 30 patients each. Time consumption, ease of application, and pain perception were evaluated at three intervals: pre-, during- and post-caries removal, using Wong-Baker FACES (WBF) Pain Rating Scale and the Face, Legs, Activity, Cry, Consolability (FLACC) scale. The results showed that among the compared materials and conventional hand instrumentation technique, Carie-Care™ was statistically found to be the least time-consuming with a p-value of 0.019, have the least pain perception with a p-value of 0.02, and was clinically the best with respect to manipulation and handling. While all three CMCR agents aid in the removal of carious tissue, Carie-Care™ was the most effective based on time consumption, pain perception and simplicity of administration.


Subject(s)
Dental Caries , Dental Cavity Preparation , Papain , Tooth, Deciduous , Humans , Dental Caries/therapy , Child, Preschool , Child , Papain/therapeutic use , Male , Female , Dental Cavity Preparation/methods , Dental Cavity Preparation/instrumentation , Pain Measurement , Lysine/therapeutic use , Molar
8.
Food Res Int ; 183: 114175, 2024 May.
Article in English | MEDLINE | ID: mdl-38760120

ABSTRACT

Lactose hydrolysed concentrated milk was prepared using ß-galactosidase enzyme (4.76U/mL) with a reaction period of 12 h at 4 °C. Addition of polysaccharides (5 % maltodextrin/ß-cyclodextrin) to concentrated milk either before or after lactose hydrolysis did not result in significant differences (p > 0.05) in degree of hydrolysis (% DH) of lactose and residual lactose content (%). Three different inlet temperatures (165 °C, 175 °C and 185 °C) were used for the preparation of powders which were later characterised based on physico-chemical and maillard browning characteristics. Moisture content, solubility and available lysine content of the powders decreased significantly, whereas, browning parameters i.e., browning index, 5-hydroxymethylfurfural, furosine content increased significantly (p < 0.05) with an increase in inlet air temperature. The powder was finally prepared with 5 % polysaccharide and an inlet air temperature of 185 °C which reduced maillard browning. Protein-polysaccharide interactions were identified using Fourier Transform infrared spectroscopy, fluorescence spectroscopy and determination of free amino groups in the powder samples. Maltodextrin and ß-cyclodextrin containing powder samples exhibited lower free amino groups and higher degree of graft value as compared to control sample which indicated protein-polysaccharide interactions. Results obtained from Fourier Transform infrared spectroscopy also confirmed strong protein-polysaccharide interactions, moreover a significant decrease in fluorescence intensity was also observed in the powder samples. These interactions between the proteins and polysaccharides reduced the maillard browning in powders.


Subject(s)
Furaldehyde , Lactose , Maillard Reaction , Milk , Polysaccharides , Powders , Lactose/chemistry , Polysaccharides/chemistry , Milk/chemistry , Animals , Spectroscopy, Fourier Transform Infrared , Furaldehyde/analogs & derivatives , Furaldehyde/chemistry , beta-Galactosidase/metabolism , beta-Cyclodextrins/chemistry , Hydrolysis , Spray Drying , Temperature , Lysine/chemistry , Lysine/analogs & derivatives , Solubility , Spectrometry, Fluorescence , Milk Proteins/chemistry , Food Handling/methods
9.
Pak J Pharm Sci ; 37(1(Special)): 245-255, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38747276

ABSTRACT

Aripiprazole (ARI), an antipsychotic having low solubility and stability. To overcome this, formation of binary and ternary using inclusion complexes of Methyl-ß-cyclodextrin (MßCD) /Hydroxy propyl beta cyclodextrin (HPßCD) and L-Arginine (ARG)/ Lysine (LYS) are analyzed by dissolution testing and phase stability study along with their complexation efficacy and solubility constants made by physical mixing. Inclusion complexes with ARG were better than LYS and prepared by solvent evaporation and lyophilization method as well. They are characterized by Attenuated Total Reflection Fourier Transform Infrared Spectroscopy (AT-FTIR), X-ray powder diffractometry (XRD), Differential Scanning Calorimetry (DSC), Scanning electron microscopy (SEM) and Thermal gravimetric analysis (TGA). The bond shifting in AT-FTIR confirmed the molecular interactions between host and guest molecules. The SEM images also confirmed a complete change of drug morphology in case of ternary inclusion complexes prepared by lyophilization method for both the polymers. ARI: MßCD: ARG when used in the specific molar ratio of 1:1:0.27 by prepared by lyophilization method has 18 times best solubility while ARI:HPßCD:ARG was 7 times best solubility than pure drug making MßCD a better choice than HPßCD. Change in the molar ratio will cause loss of stability or solubility. Solvent evaporation gave significant level of solubility but less stability.


Subject(s)
2-Hydroxypropyl-beta-cyclodextrin , Arginine , Aripiprazole , Calorimetry, Differential Scanning , Lysine , Solubility , beta-Cyclodextrins , Aripiprazole/chemistry , Arginine/chemistry , beta-Cyclodextrins/chemistry , 2-Hydroxypropyl-beta-cyclodextrin/chemistry , Lysine/chemistry , Spectroscopy, Fourier Transform Infrared , X-Ray Diffraction , Freeze Drying , Antipsychotic Agents/chemistry , Drug Stability , Microscopy, Electron, Scanning , Drug Compounding , Chemistry, Pharmaceutical/methods
10.
BMC Biol ; 22(1): 113, 2024 May 15.
Article in English | MEDLINE | ID: mdl-38750524

ABSTRACT

BACKGROUND: Protein posttranslational modifications (PTMs) are fast and early responses to environmental changes, including pathogen infection. Jujube witches' broom (JWB) is a phytoplasma disease causing great economic loss in jujube production. After phytoplasma infection, the transcriptional, translational, and metabolic levels in jujube were activated, enabling it to survive during phytoplasma invasion. However, no study has yet reported on PTMs in jujube. Lysine crotonylation (Kcr) and lysine succinylation (Ksu) have been popular studies in recent years and their function in plant phytoplasma-stress responses remains unclear. RESULTS: Here, 1656 crotonylated and 282 succinylated jujube proteins were first identified under phytoplasma-stress, of which 198 were simultaneously crotonylated and succinylated. Comparative analysis revealed that 656 proteins, 137 crotonylated and 43 succinylated proteins in jujube were regulated by phytoplasma infection, suggesting that Kcr was more universal than Ksu. Kcr differentially expressed proteins (DEPs) were related to ribosomes, photosynthetic and carbon metabolism, while Ksu DEPs were mainly involved in carbon metabolism, the TCA cycle and secondary metabolite biosynthesis. The crosstalk network among proteome, crotonylome and succinylome showed that DEPs related to ribosomal, peroxidases and glutathione redox were enriched. Among them, ZjPOD51 and ZjPHGPX2 significantly increased at the protein and Kcr level under phytoplasma-stress. Notably, 7 Kcr sites were identified in ZjPHGPX2, a unique antioxidant enzyme. After inhibitor nicotinamide (NAM) treatment, GPX enzyme activity in jujube seedlings was reduced. Further, site-directed mutagenesis of key Kcr modification sites K130 and/or K135 in ZjPHGPX2 significantly reduced its activity. CONCLUSIONS: This study firstly provided large-scale datasets of Kcr and Ksu in phytoplasma-infected jujube and revealed that Kcr modification in ZjPHGPX2 positively regulates its activity.


Subject(s)
Phytoplasma , Plant Diseases , Plant Proteins , Ziziphus , Ziziphus/microbiology , Ziziphus/metabolism , Phytoplasma/physiology , Plant Proteins/metabolism , Plant Proteins/genetics , Plant Diseases/microbiology , Protein Processing, Post-Translational , Stress, Physiological , Lysine/metabolism
11.
Front Endocrinol (Lausanne) ; 15: 1328679, 2024.
Article in English | MEDLINE | ID: mdl-38779451

ABSTRACT

Objective: The established link between posttranslational modifications of histone and non-histone lysine (K) residues in cell metabolism, and their role in cancer progression, is well-documented. However, the lactylation expression signature in triple-negative breast cancer (TNBC) remains underexplored. Methods: We conducted a comprehensive lactylproteome profiling of eight pairs of TNBC samples and their matched adjacent tissues. This was achieved through 4-Dimensional label-free quantitative proteomics combined with lactylation analysis (4D-LFQP-LA). The expression of identified lactylated proteins in TNBC was detected using immunoblotting and immunohistochemistry (IHC) with specific primary antibodies, and their clinicopathological and prognostic significance was evaluated. Results: Our analysis identified 58 lactylation sites on 48 proteins, delineating the protein lactylation alteration signature in TNBC. Bioinformatic and functional analyses indicated that these lactylated proteins play crucial roles in regulating key biological processes in TNBC. Notably, lactylation of lysine at position 12 (H4K12lac) in the histone H4 domain was found to be upregulated in TNBC. Further investigations showed a high prevalence of H4K12lac upregulation in TNBC, with positive rates of 93.19% (137/147) and 92.93% (92/99) in TNBC tissue chip and validation cohorts, respectively. H4K12lac expression correlated positively with Ki-67 and inversely with overall survival (OS) in TNBC (HR [hazard ratio] =2.813, 95%CI [credibility interval]: 1.242-6.371, P=0.0164), suggesting its potential as an independent prognostic marker (HR=3.477, 95%CI: 1.324-9.130, P=0.011). Conclusions: Lactylation is a significant post-translational modification in TNBC proteins. H4K12lac emerges as a promising biomarker for TNBC, offering insights into the lactylation profiles of TNBC proteins and linking histone modifications to clinical implications in TNBC.


Subject(s)
Biomarkers, Tumor , Histones , Protein Processing, Post-Translational , Triple Negative Breast Neoplasms , Triple Negative Breast Neoplasms/metabolism , Triple Negative Breast Neoplasms/pathology , Humans , Histones/metabolism , Female , Biomarkers, Tumor/metabolism , Prognosis , Middle Aged , Proteomics/methods , Proteome/metabolism , Adult , Lysine/metabolism
12.
Sci Rep ; 14(1): 10295, 2024 05 04.
Article in English | MEDLINE | ID: mdl-38704415

ABSTRACT

Lysine crotonylation (Kcr) is a recently discovered histone acylation modification that is closely associated with gene expression, cell proliferation, and the maintenance of stem cell pluripotency and indicates the transcriptional activity of genes and the regulation of various biological processes. During cell culture, the introduction of exogenous croconic acid disodium salt (Nacr) has been shown to modulate intracellular Kcr levels. Although research on Kcr has increased, its role in cell growth and proliferation and its potential regulatory mechanisms remain unclear compared to those of histone methylation and acetylation. Our investigation demonstrated that the addition of 5 mM Nacr to cultured bovine fibroblasts increased the expression of genes associated with Kcr modification, ultimately promoting cell growth and stimulating cell proliferation. Somatic cell nuclear transfer of donor cells cultured in 5 mM Nacr resulted in 38.1% blastocyst development, which was significantly greater than that in the control group (25.2%). This research is important for elucidating the crotonylation modification mechanism in fibroblast proliferation to promote the efficacy of somatic cell nuclear transfer.


Subject(s)
Cell Proliferation , Fibroblasts , Histones , Nuclear Transfer Techniques , Animals , Cattle , Fibroblasts/metabolism , Fibroblasts/cytology , Cell Proliferation/drug effects , Histones/metabolism , Embryonic Development , Blastocyst/metabolism , Blastocyst/cytology , Lysine/metabolism , Crotonates/metabolism , Cells, Cultured , Protein Processing, Post-Translational , Female
13.
Food Res Int ; 187: 114405, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38763659

ABSTRACT

Sojae semen praeparatum (SSP), a fermented product known for its distinctive flavor and medicinal properties, undergoes a complex fermentation process due to the action of various microorganisms. Despite its widespread use, the effect of these microorganisms on the flavor compounds and functional components of SSP remains poorly understood. This study aimed to shed light on this aspect by identifying 20 metabolites as potential key flavor substances in SSP. Moreover, glycine and lysine were identified as crucial flavor substances. Additionally, 24 metabolites were identified as key functional components. The dominant microorganisms involved in the fermentation process were examined, revealing six genera of fungi and 12 genera of bacteria. At the species level, 16 microorganisms were identified as dominant through metagenome sequencing. Spearman correlation analysis demonstrated a strong association between dominant microorganisms and both flavor substances and functional components. Furthermore, the study validated the significance of four core functional microorganisms in improving the flavor and quality of SSP. This comprehensive exploration of functional microorganisms of SSP on key flavor substances/functional components during SSP fermentation. The study findings serve as a valuable reference for enhancing the overall flavor and quality of SSP.


Subject(s)
Bacteria , Fermentation , High-Throughput Nucleotide Sequencing , Metabolomics , Bacteria/metabolism , Bacteria/genetics , Bacteria/classification , Flavoring Agents/metabolism , Taste , Fungi/metabolism , Fungi/genetics , Food Microbiology , Fermented Foods/microbiology , Lysine/metabolism
14.
J Med Chem ; 67(10): 8186-8200, 2024 May 23.
Article in English | MEDLINE | ID: mdl-38733345

ABSTRACT

The ATPase family AAA+ domain containing 2 (ATAD2) protein and its paralog ATAD2B have a C-terminal bromodomain (BRD) that functions as a reader of acetylated lysine residues on histone proteins. Using a structure-function approach, we investigated the ability of the ATAD2/B BRDs to select acetylated lysine among multiple histone post-translational modifications. The ATAD2B BRD can bind acetylated histone ligands that also contain adjacent methylation or phosphorylation marks, while the presence of these modifications significantly weakened the acetyllysine binding activity of the ATAD2 BRD. Our structural studies provide mechanistic insights into how ATAD2/B BRD-binding pocket residues coordinate the acetyllysine group in the context of adjacent post-translational modifications. Furthermore, we investigated how sequence changes in amino acids of the histone ligands impact the recognition of an adjacent acetyllysine residue. Our study highlights how the interplay between multiple combinations of histone modifications influences the reader activity of the ATAD2/B BRDs, resulting in distinct binding modes.


Subject(s)
ATPases Associated with Diverse Cellular Activities , DNA-Binding Proteins , Histones , Lysine , Histones/metabolism , Histones/chemistry , ATPases Associated with Diverse Cellular Activities/metabolism , ATPases Associated with Diverse Cellular Activities/chemistry , Humans , DNA-Binding Proteins/metabolism , DNA-Binding Proteins/chemistry , Lysine/metabolism , Lysine/chemistry , Acetylation , Protein Processing, Post-Translational , Adenosine Triphosphatases/metabolism , Adenosine Triphosphatases/chemistry , Protein Binding , Protein Domains , Models, Molecular , Binding Sites
15.
Bioorg Med Chem ; 106: 117735, 2024 May 15.
Article in English | MEDLINE | ID: mdl-38714021

ABSTRACT

Numerous natural antimicrobial peptides (AMPs) exhibit a cationic amphipathic helical conformation, wherein cationic amino acids, such as lysine and arginine, play pivotal roles in antimicrobial activity by aiding initial attraction to negatively charged bacterial membranes. Expanding on our previous work, which introduced a de novo design of amphipathic helices within cationic heptapeptides using an 'all-hydrocarbon peptide stapling' approach, we investigated the impact of lysine-homologue substitution on helix formation, antimicrobial activity, hemolytic activity, and proteolytic stability of these novel AMPs. Our results demonstrate that substituting lysine with ornithine enhances both the antimicrobial activity and proteolytic stability of the stapled heptapeptide AMP series, while maintaining low hemolytic activity. This finding underscores lysine-homologue substitution as a valuable strategy for optimizing the therapeutic potential of diverse cationic AMPs.


Subject(s)
Anti-Bacterial Agents , Antimicrobial Cationic Peptides , Hemolysis , Lysine , Microbial Sensitivity Tests , Lysine/chemistry , Lysine/pharmacology , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/chemical synthesis , Hemolysis/drug effects , Antimicrobial Cationic Peptides/chemistry , Antimicrobial Cationic Peptides/pharmacology , Antimicrobial Cationic Peptides/chemical synthesis , Structure-Activity Relationship , Proteolysis/drug effects , Humans , Molecular Structure
16.
Int J Mol Sci ; 25(9)2024 Apr 28.
Article in English | MEDLINE | ID: mdl-38732042

ABSTRACT

Numerous post-translational modifications are involved in oocyte maturation and embryo development. Recently, lactylation has emerged as a novel epigenetic modification implicated in the regulation of diverse cellular processes. However, it remains unclear whether lactylation occurs during oocyte maturation and embryo development processes. Herein, the lysine lactylation (Kla) modifications were determined during mouse oocyte maturation and early embryo development by immunofluorescence staining. Exogenous lactate was supplemented to explore the consequences of modulating histone lactylation levels on oocyte maturation and embryo development processes by transcriptomics. Results demonstrated that lactylated proteins are widely present in mice with tissue- and cell-specific distribution. During mouse oocyte maturation, immunofluorescence for H3K9la, H3K14la, H4K8la, and H4K12la was most intense at the germinal vesicle (GV) stage and subsequently weakened or disappeared. Further, supplementing the culture medium with 10 mM sodium lactate elevated both the oocyte maturation rate and the histone Kla levels in GV oocytes, and there were substantial increases in Kla levels in metaphase II (MII) oocytes. It altered the transcription of molecules involved in oxidative phosphorylation. Moreover, histone lactylation levels changed dynamically during mouse early embryogenesis. Sodium lactate at 10 mM enhanced early embryo development and significantly increased lactylation, while impacting glycolytic gene transcription. This study reveals the roles of lactylation during oocyte maturation and embryo development, providing new insights to improving oocyte maturation and embryo quality.


Subject(s)
Embryonic Development , Histones , Oocytes , Protein Processing, Post-Translational , Animals , Histones/metabolism , Oocytes/metabolism , Mice , Embryonic Development/genetics , Female , Oogenesis , Lysine/metabolism , In Vitro Oocyte Maturation Techniques , Gene Expression Regulation, Developmental
17.
Int J Mol Sci ; 25(9)2024 Apr 29.
Article in English | MEDLINE | ID: mdl-38732083

ABSTRACT

Three new phenanthridine peptide derivatives (19, 22, and 23) were synthesized to explore their potential as spectrophotometric probes for DNA and RNA. UV/Vis and circular dichroism (CD) spectra, mass spectroscopy, and computational analysis confirmed the presence of intramolecular interactions in all three compounds. Computational analysis revealed that compounds alternate between bent and open conformations, highlighting the latter's crucial influence on successful polynucleotide recognition. Substituting one glycine with lysine in two regioisomers (22, 23) resulted in stronger binding interactions with DNA and RNA than for a compound containing two glycines (19), thus emphasizing the importance of lysine. The regioisomer with lysine closer to the phenanthridine ring (23) exhibited a dual and selective fluorimetric response with non-alternating AT and ATT polynucleotides and induction of triplex formation from the AT duplex. The best binding constant (K) with a value of 2.5 × 107 M-1 was obtained for the interaction with AT and ATT polynucleotides. Furthermore, apart from distinguishing between different types of ds-DNA and ds-RNA, the same compound could recognize GC-rich DNA through distinct induced CD signals.


Subject(s)
Circular Dichroism , DNA , Lysine , Peptides , Phenanthridines , Phenanthridines/chemistry , Lysine/chemistry , Peptides/chemistry , DNA/chemistry , DNA/metabolism , RNA/chemistry , Nucleic Acid Conformation
18.
Nat Commun ; 15(1): 4023, 2024 May 13.
Article in English | MEDLINE | ID: mdl-38740816

ABSTRACT

Abscission is the final stage of cytokinesis, which cleaves the intercellular bridge (ICB) connecting two daughter cells. Abscission requires tight control of the recruitment and polymerization of the Endosomal Protein Complex Required for Transport-III (ESCRT-III) components. We explore the role of post-translational modifications in regulating ESCRT dynamics. We discover that SMYD2 methylates the lysine 6 residue of human CHMP2B, a key ESCRT-III component, at the ICB, impacting the dynamic relocation of CHMP2B to sites of abscission. SMYD2 loss-of-function (genetically or pharmacologically) causes CHMP2B hypomethylation, delayed CHMP2B polymerization and delayed abscission. This is phenocopied by CHMP2B lysine 6 mutants that cannot be methylated. Conversely, SMYD2 gain-of-function causes CHMP2B hypermethylation and accelerated abscission, specifically in cells undergoing cytokinetic challenges, thereby bypassing the abscission checkpoint. Additional experiments highlight the importance of CHMP2B methylation beyond cytokinesis, namely during ESCRT-III-mediated HIV-1 budding. We propose that lysine methylation signaling fine-tunes the ESCRT-III machinery to regulate the timing of cytokinetic abscission and other ESCRT-III dependent functions.


Subject(s)
Cytokinesis , Endosomal Sorting Complexes Required for Transport , Endosomal Sorting Complexes Required for Transport/metabolism , Endosomal Sorting Complexes Required for Transport/genetics , Humans , Methylation , HeLa Cells , Histone-Lysine N-Methyltransferase/metabolism , Histone-Lysine N-Methyltransferase/genetics , HIV-1/metabolism , HIV-1/genetics , HIV-1/physiology , Lysine/metabolism , Protein Processing, Post-Translational
19.
J Anim Sci ; 1022024 Jan 03.
Article in English | MEDLINE | ID: mdl-38733259

ABSTRACT

An experiment was conducted to assess the effects of porcine somatotropin (pST) on the responses to a near-ideal blend of AA on the AA composition of empty, whole-empty body (WEB) protein and WEB essential AA accretion rate in pigs from 22 to 60 kg BW. Forty Hampshire × Yorkshire gilts were individually penned and assigned to a 4 × 2 factorial arrangement of treatments consisting of four diets with and without pST injection. A fortified corn-soybean meal basal diet was formulated to contain 1.50% total Lys with Thr, Met, and Trp added to obtain a near-ideal blend of these AA relative to Lys. In three additional diets, Lys was reduced to 1.25%, 1.00%, and 0.75% by diluting the basal diet with cornstarch, cellulose, and sand such that the diets also contained the same ratios of AA. Pigs that received pST were administered a daily i.m. injection of 2 mg of pST. At 60 kg BW, the WEB (carcass, head, viscera, blood, nails, and hair) was ground and analyzed for proximate and AA composition. Administration of pST increased (P < 0.001) accretion rates of WEB protein and essential AA. Increasing dietary essential AA increased (quadratic, P < 0.03) accretion rate of WEB protein, His, Leu, Trp, and Val in pST-treated pigs, but not in untreated pigs. Lysine composition in the accreted WEB protein was not affected (P > 0.05) by dietary Lys. The efficiency of Lys utilization for WEB Lys accretion was linearly affected (P < 0.01) by dietary Lys. These results indicated that the dietary Lys needed to achieve maximum WEB Lys accretion is markedly increased by pST administration.


This study evaluated the effects of two factors, porcine somatotropin and graded levels of amino acids, on the total accumulation and the accretion rate of amino acids across a broad range of protein deposition rates in growing pigs. Treatments included 1) with or without a daily injection of porcine somatotropin and 2) graded levels of total dietary lysine from 0.75% to 1.50%. As expected, both the administration of porcine somatotropin and increased dietary lysine increased both the amount and the rate of amino acid accretion. However, the amount and rate of amino acid accretion from increased dietary amino acids were markedly greater in pigs treated with porcine somatotropin. Thus, the extent to which the genetic potential for protein deposition is achieved depends on both the anabolic capacity of the pig and the amino acid concentration of the diet provided.


Subject(s)
Amino Acids , Animal Feed , Animal Nutritional Physiological Phenomena , Diet , Growth Hormone , Lysine , Animals , Animal Feed/analysis , Lysine/pharmacology , Lysine/administration & dosage , Lysine/chemistry , Diet/veterinary , Female , Growth Hormone/pharmacology , Amino Acids/metabolism , Amino Acids/pharmacology , Swine/growth & development , Dietary Supplements/analysis , Body Composition/drug effects
20.
Clin Nucl Med ; 49(7): e338-e339, 2024 Jul 01.
Article in English | MEDLINE | ID: mdl-38739487

ABSTRACT

ABSTRACT: Peripheral T-cell lymphomas are a heterogenous group of lymphomas with a high rate of extranodal disease. We present a case of increased 18 F-DCFPyL uptake in peripheral T-cell lymphoma of subcutaneous tissue and bone. Familiarity with the increased 18 F-DCFPyL uptake and extranodal presentation of peripheral T-cell lymphomas can avoid misinterpretation for metastatic disease.


Subject(s)
Antigens, Surface , Glutamate Carboxypeptidase II , Lymphoma, T-Cell, Peripheral , Lysine , Humans , Lymphoma, T-Cell, Peripheral/diagnostic imaging , Lymphoma, T-Cell, Peripheral/drug therapy , Glutamate Carboxypeptidase II/metabolism , Male , Lysine/analogs & derivatives , Lysine/metabolism , Antigens, Surface/metabolism , Urea/analogs & derivatives , Urea/pharmacology , Positron Emission Tomography Computed Tomography , Biological Transport , Middle Aged
SELECTION OF CITATIONS
SEARCH DETAIL
...