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1.
Phytopathology ; 2020 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-32065037

RESUMO

Fusarium oxysporum f. sp. sesami (Fos) is an extremely destructive pathogen, causing sesame Fusarium wilt disease worldwide. To clarify the pathogenicity and the genetic characters of Fos, we systematically investigated 69 F. oxysporum isolates collected from major sesame-growing areas in China. Among these isolates, 54 isolates were pathogenic and 15 were non-pathogenic according to pathogenicity testing on sesame seedlings. For the pathogenic isolates, three Fos pathogenic groups were defined based on the three differential sesame hosts for the first time. A translation elongation factor 1a (EF-1a) gene tree was constructed to determine the genetic diversity of the F. oxysporum isolates, but could not separated Fos isolates from the non-pathogenic isolates and other F. oxysporum formae speciales. Ten Secreted In Xylem (SIX) genes, one family of effectors, were identified in Fos isolates by a search with the genome data, and were subsequently screened in the 69 F. oxysporum isolates. Compared with the SIX gene profiles in other F. oxysporum formae speciales, the presence and sequence variations of the SIX gene homologues directly correlated with the specific pathogenicity of Fos toward sesame. Furthermore, eight of these Fos SIX genes were significantly expressed in sesame plants as infection of the Fos isolate. The findings have important significance for understanding the pathogenic basis of Fos isolates, and will contribute to improve the diagnostics to effectively control Fusarium wilt disease in sesame.

2.
Sci Total Environ ; 715: 136942, 2020 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-32007895

RESUMO

Aluminum (Al) is an inorganic pollutant that induces nerve cells apoptosis and necroptosis, thereby causing depression and neurodegenerative diseases. IL-1ß/JNK signaling pathway can regulate apoptosis and necroptosis. However, it remains unclear whether IL-1ß/JNK signaling pathway is involving in the regulation of Al-induced hippocampal neural cells apoptosis and necroptosis. To investigate the mechanism of Al on neural cells apoptosis and necroptosis, rats were orally exposed to different doses of AlCl3 for 90 days. The open-field test results showed that AlCl3 caused depressive behavior in rats. Histopathological evidence showed that AlCl3 induced hippocampal neural cells apoptosis and necrosis. Moreover, Bax/Bcl-2 mRNA expression ratio, caspase-3 activity and mRNA expression and TUNEL positive rates were upregulated, meanwhile, TNF-α mRNA and protein expression levels, TNFR1, RIP1, RIP3 and MLKL proteins levels were increased, while caspase-8 protein level was decreased in the hippocampus of Al-exposed groups. These results proved that AlCl3 induced hippocampal neural cells apoptosis and necroptosis. Combined with histopathology and correlation analysis, we deduced that hippocampal neural cells were more likely to undergo necroptosis at high doses (450 mg/kg) of AlCl3, while <150 mg/kg AlCl3 tended to induce apoptosis. Finally, AlCl3 increased the proteins level of IL-1ß, IL-1RI, IL-1RAcP, JNK and p-JNK, indicating that AlCl3 activated IL-1ß/JNK signaling pathway. However, the application of IL-1 receptor antagonist (IL-1Ra) inhibited the phosphorylation of JNK and the related genes expression of apoptosis and necroptosis caused by AlCl3. Thus, we concluded that AlCl3 induced hippocampal neural cells death and depression-like behavior in rats by activating IL-1ß/JNK signaling pathway.

3.
Mol Oncol ; 2020 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-31901148

RESUMO

Malignant tumors, including colorectal cancer (CRC), usually rely on ATP generation through aerobic glycolysis for both rapid growth and chemotherapy resistance. The M2 isoform of pyruvate kinase (PKM2) has a key role in catalyzing glycolysis, and PKM2 expression varies even within a single tumor. In this study, we confirmed that expression of PKM2 is heterogeneous in CRC cells, namely high in oxaliplatin-resistant cells but relatively low in sensitive cells, and found that chemoresistant cells had enhanced glycolysis and ATP production. In addition, we report a PKM2-dependent mechanism through which chemosensitive cells may gradually transform into chemoresistant cells. The circular RNA hsa_circ_0005963 (termed ciRS-122 in this study), which was determined to be a sponge for the PKM2-targeting miR-122, was positively correlated with chemoresistance. In vitro and in vivo studies showed that exosomes from oxaliplatin-resistant cells delivered ciRS-122 to sensitive cells, thereby promoting glycolysis and drug resistance through miR-122 sponging and PKM2 upregulation. Moreover, si-ciRS-122 transported by exosomes could suppress glycolysis and reverse resistance to oxaliplatin by regulating the ciRS-122-miR-122-PKM2 pathway in vivo. Exosomes derived from chemoresistant CRC cells could transfer ciRS-122 across cells and promote glycolysis to reduce drug susceptibility in chemosensitive cells. This intercellular signal delivery suggests a potential novel therapeutic target and establishes a foundation for future clinical applications in drug-resistant CRC.

4.
Genes Genomics ; 42(1): 25-39, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31677128

RESUMO

BACKGROUND: Both photosynthetic pigments and chloroplasts in plant leaf cells play an important role in deciding on the photosynthetic capacity and efficiency in plants. Systematical investigating the regulatory mechanism of chloroplast development and chlorophyll (Chl) content variation is necessary for clarifying the photosynthesis mechanism for crops. OBJECTIVE: This study aims to explore the critical regulatory mechanism of leaf color mutation in a yellow-green leaf sesame mutant Siyl-1. METHODS: We performed the genetic analysis of the yellow-green leaf color mutation using the F2 population of the mutant Siyl-1. We compared the morphological structure of the chloroplasts, chlorophyll content of the three genotypes of the mutant F2 progeny. We performed the two-dimensional gel electrophoresis (2-DE) and compared the protein expression variation between the mutant progeny and the wild type. RESULTS: Genetic analysis indicated that there were 3 phenotypes of the F2 population of the mutant Siyl-1, i.e., YY type with light-yellow leaf color (lethal); Yy type with yellow-green leaf color, and yy type with normal green leaf color. The yellow-green mutation was controlled by an incompletely dominant nuclear gene, Siyl-1. Compared with the wild genotype, the chloroplast number and the morphological structure in YY and Yy mutant lines varied evidently. The chlorophyll content also significantly decreased (P < 0.05). The 2-DE comparison showed that there were 98 differentially expressed proteins (DEPs) among YY, Yy, and yy lines. All the 98 DEPs were classified into 5 functional groups. Of which 82.7% DEPs proteins belonged to the photosynthesis and energy metabolism group. CONCLUSION: The results revealed the genetic character of yellow-green leaf color mutant Siyl-1. 98 DEPs were found in YY and Yy mutant compared with the wild genotype. The regulation pathway related with the yellow leaf trait mutation in sesame was analyzed for the first time. The findings supplied the basic theoretical and gene basis for leaf color and chloroplast development mechanism in sesame.

5.
Theor Appl Genet ; 133(1): 73-86, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31686114

RESUMO

KEY MESSAGE: SiDWF1 encodes a gibberellin receptor GID1B-like protein controlling the internode length and plant height in sesame. Sesame is a high-height crop. Here we systematically analyzed the morphological and genetic characters of the sesame dwarf mutant dw607 (dwf1 type). The plant height and the internode length of dw607 significantly declined, while the thousand seed weight (TSW) significantly increased (P < 0.01). The cell size of stem parenchyma and pith tissue reduced, and vascular bundle cells and parenchyma tissue arranged much tighter in the dwarf mutant. Based on the cross-population association mapping of a RIL population of the cross 'dw607 (dwf1) × 15N41 (wt type),' the target interval linked to the short internode length was located on C9.scaffold2 of SiChr.4 in sesame. We further screened the 58 variants using the genomic variant data of 824 germplasm and BSA DNA pools and determined the target gene Sidwf1. The SNP mutation of C1057 to T1057 resulted in the amino acid change of P150 (proline) to S150 (serine) in SiDWF1. SiDWF1 gene allele is 1,638 bp and encodes a gibberellin receptor GID1B-like protein. Transcription profile assay reflected that Sidwf1 is highly expressed in leaf, stem, bud, and capsule tissues. The dynamic variation in endogenous GA3 content in dw607 and the wild type was also monitored in this study. The results revealed the molecular genetic mechanism of the internode length and plant height trait in sesame for the first time. The findings supply the theoretical and material basis for developing the marker-assisted selection (MAS) breeding in sesame.

6.
Food Chem ; 308: 125596, 2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-31648097

RESUMO

The protective mechanism of glycerol on ß-lactoglobulin were studied in 0-60% glycerol solutions by experimental and molecular simulation approaches. Results showed that the stability of ß-lactoglobulin increased with glycerol concentration, with little secondary structure changes induced by glycerol. The tertiary structure altered slightly with glycerol concentration, resulting in a stronger near UV circular dichroism signal and intrinsic tryptophan fluorescence quenching, indicating aromatic side chains closer to hydrophobic microenvironment. The Rg of ß-lactoglobulin increased with glycerol concentration without dimer dissociation, due to expansion of the quaternary structures. Moreover, the flexibility (RMSF) of ß-lactoglobulin decreased by glycerol. Distance between areas enclosing Asp33 and Arg40 from separate chains did not increase, suggesting possibly reinforced electrostatic attractions. In conclusion, the stabilization of ß-lactoglobulin in glycerol solution is probably the comprehensive results of the decreased molecular flexibility, the strengthened hydrophobic interaction in individual chain, and the possibly reinforced electrostatic attractions between two chains of ß-lactoglobulin.


Assuntos
Glicerol/química , Lactoglobulinas/química , Dicroísmo Circular , Interações Hidrofóbicas e Hidrofílicas , Modelos Moleculares , Estrutura Secundária de Proteína , Estrutura Terciária de Proteína
7.
Food Chem ; 311: 125911, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-31869650

RESUMO

Milk allergenic proteins are the main reason of cow's milk allergy. The most common method for removing milk allergenic proteins is enzymatic hydrolysis. However, the direct application of protease to hydrolyze allergens will lead to the introduction of new allergenic proteins. An ideal strategy for removing milk allergenic proteins without introducing new allergenic proteins is immobilization of protease. Herein, we established a simple method to synthesize a novel papain-Cu3(PO4)2·3H2O-magnetic nanoflowers (PCMNs). The PCMNs demonstrated 1556% higher activity than the free alkaline papain. Moreover, the PCMNs could hydrolyze most of allergenic proteins in cow's milk, generating low-sensitive milk. In cycle analysis, the PCMNs also exhibited good reusability and were easily separated from the product.

8.
Sci Rep ; 9(1): 19109, 2019 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-31836801

RESUMO

The encystment of many ciliates is an advanced survival strategy against adversity and the most important reason for ciliates existence worldwide. However, the molecular mechanism for the encystment of free-living ciliates is poorly understood. Here, we performed comparative transcriptomic analysis of dormant cysts and trophonts from Pseudourostyla cristata using transcriptomics, qRT-PCR and bioinformatic techniques. We identified 2565 differentially expressed unigenes between the dormant cysts and the trophonts. The total number of differentially expressed genes in GO database was 1752. The differential unigenes noted to the GO terms were 1993. These differential categories were mainly related to polyamine transport, pectin decomposition, cytoplasmic translation, ribosome, respiratory chain, ribosome structure, ion channel activity, and RNA ligation. A total of 224 different pathways were mapped. Among them, 184 pathways were upregulated, while 162 were downregulated. Further investigation showed that the calcium and AMPK signaling pathway had important induction effects on the encystment. In addition, FOXO and ubiquitin-mediated proteolysis signaling pathway jointly regulated the encystment. Based on these findings, we propose a hypothetical signaling network that regulates Pseudourostyla cristata encystment. Overall, these results provide deeper insights into the molecular mechanisms of ciliates encystment and adaptation to adverse environments.

9.
Mol Ther Oncolytics ; 15: 223-233, 2019 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-31828217

RESUMO

Gastric cancer (GC) has a poor prognosis due to its relentless proliferation and metastasis. One of the reasons for this plight is the formidable angiogenesis ability of GC. Considering the important role of cancer exosomes as carriers and communicators in the tumor microenvironment, we explored the role of exosome-microRNA (miRNA) in regulating angiogenesis. Western blotting and quantitative real-time PCR were used to measure the protein and mRNA levels of the miRNA target gene. To detect changes in cellular biological functions, we pretreated human umbilical vein endothelial cells (HUVECs) that were severally cocultured with GC-derived exosomes and transfected them with different miRNAs directly. Also, we used the mouse xenograft model to verify the effect of miR-155 on angiogenesis of GC tissues in vivo. Our study confirmed that miR-155, as a driver of angiogenesis, encapsulated by exosomes from GC can enhance the generation of new vessels for GC in vitro through inhibiting the expression of Forkhead box O3 (FOXO3a) protein, which led to the progression of GC. Therefore, miR-155 is probable to become a potential biomarker for the detection of migration and angiogenesis of GC, and serves as a novel target for anti-angiogenesis therapy.

10.
Artigo em Inglês | MEDLINE | ID: mdl-31870995

RESUMO

This article studies the event-triggered stochastic synchronization problem for neutral-type semi-Markovian jump (SMJ) neural networks with partial mode-dependent additive time-varying delays (ATDs), where the SMJ parameters in two ATDs are considered to be not completely the same as the one in the connection weight matrices of the systems. Different from the weak infinitesimal operator of multi-Markov processes, a new one for the double semi-Markovian processes (SMPs) is first proposed. To reduce the conservative of the stability criteria, a generalized reciprocally convex combination inequality (RCCI) is established by the virtue of an interesting technique. Then, based on an eligible stochastic Lyapunov-Krasovski functional, three novel stability criteria for the studied systems are derived by employing the new RCCI and combining with a well-designed event-triggered control scheme. Finally, three numerical examples and one practical engineering example are presented to show the validity of our methods.

11.
Appl Opt ; 58(33): 9230-9239, 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31873602

RESUMO

A mini-camera is one of several emerging cat-eye devices featuring tiny lenses with diffracted retro-reflections. It is hard for traditional active laser detection systems to identify a mini-camera because of their weak reflection. This paper proposes an anti-camera system with a spectrum-based convolutional neural network algorithm to recognize the profile features of the retro-reflection images captured by the system. The network was trained with the spatial spectra of local datasets and uploaded onto the embedded device. The results of several indoor experiments demonstrate that the system reached high accuracy in real-time detection, even with various types of interference.

12.
BMC Plant Biol ; 19(1): 588, 2019 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-31881840

RESUMO

BACKGROUND: Sesame (Sesamum indicum L., 2n = 2x = 26) is an important oilseed crop with high oil content but small seed size. To reveal the genetic loci of the quantitative seed-related traits, we constructed a high-density single nucleotide polymorphism (SNP) linkage map of an F2 population by using specific length amplified fragment (SLAF) technique and determined the quantitative trait loci (QTLs) of seed-related traits for sesame based on the phenotypes of F3 progeny. RESULTS: The genetic map comprised 2159 SNP markers distributed on 13 linkage groups (LGs) and was 2128.51 cM in length, with an average distance of 0.99 cM between adjacent markers. QTL mapping revealed 19 major-effect QTLs with the phenotypic effect (R2) more than 10%, i.e., eight QTLs for seed coat color, nine QTLs for seed size, and two QTLs for 1000-seed weight (TSW), using composite interval mapping method. Particularly, LG04 and LG11 contained collocated QTL regions for the seed coat color and seed size traits, respectively, based on their close or identical locations. In total, 155 candidate genes for seed coat color, 22 for seed size traits, and 54 for TSW were screened and analyzed. CONCLUSIONS: This report presents the first QTL mapping of seed-related traits in sesame using an F2 population. The results reveal the location of specific markers associated with seed-related traits in sesame and provide the basis for further seed quality traits research.

13.
Rev Sci Instrum ; 90(11): 115103, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31779374

RESUMO

A magnetic sensor of the optically pumped magnetometer may enter a dead zone during an aeromagnetic survey, resulting in unavoidable abnormal data and seriously affecting the effect of aeromagnetic compensation. We propose a fast discrimination and culling method based on the Hough transform to prevent abnormal data from participating in the coefficient estimation. In the proposed method, the parameter space is partitioned into small buckets and the most frequently passed region of sinusoidal curves is detected to eliminate abnormal data. Although the conventional method performs similarly to the proposed method when there is only 1% abnormal data, it is theoretically shown that the proposed method has a better goodness of fit of 0.9518, compared with a value of 0.1956 for the conventional method, in the presence of 45% abnormal data. Furthermore, we construct an experimental platform and conduct a flight test in which the proposed method has an improvement ratio of 4.11 compared with a value of 0.34 for the conventional method.

14.
Environ Toxicol ; 2019 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-31680430

RESUMO

In recent years, the protective effect of hydrogensulfide donor sodium hydrosulfide(NaHS) on multiple organs has been widely reported. The study aimed to explorethe effect of commonly used concentration of NaHS on theliver and its potential damage mechanism. Rats divided into 4 groups: control, NaHS I (1 mg/kg), II (3 mg/kg) and III(5 mg/kg) groups, and each group is divided into four-timepoints (2, 6, 12, and 24 hours). Results showed that H2S concentration increased, mitochondrial complex IV activity inhibited, the COX I and IV subunits and mitochondrial apoptosis pathway-related proteins expression increased in atime- and dose-dependent manner. We confirmed that 1 mg/kg NaHS had no injuryeffect on the liver, 3 and 5 mg/kg NaHS inhibitsthe activity of mitochondrial complex IV by promoting COX I and IV subunits expression, leading to the increase in ROS and ultimately inducing apoptosis and liver injury.

15.
J Agric Food Chem ; 67(47): 13119-13126, 2019 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-31686506

RESUMO

Phospholipids have been widely used in food, medicine, cosmetics, and other fields because of their unique chemical structure and healthcare functions. Phospholipase D (PLD) is a key biocatalyst for the biotransformation of phospholipids. Here, an autodisplay expression system was constructed for rapid screening of mutants, and PLD variants were recombined using DNA shuffling technology and three beneficial mutations were obtained. The results of enzymatic performance and sequence information comparison indicated that C-terminal amino acids exerted a greater impact on the correct folding of PLDs, and N-terminal amino acids are more important for catalytic reaction. The best-performing recombinant enzyme in transphosphatidylation reactions was Recom-34, with a phosphatidylserine content accounting for 80.3% of total phospholipids and a 3.24-fold increased conversion rate compared to the parent enzyme. This study demonstrates great significance for screening ideal biocatalysts, facilitating soluble expression of inclusion body proteins, and identifying key amino acids.


Assuntos
Proteínas de Bactérias/genética , Fosfatidilserinas/biossíntese , Fosfolipase D/genética , Streptomyces/enzimologia , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Embaralhamento de DNA , Evolução Molecular Direcionada , Fosfolipase D/química , Fosfolipase D/metabolismo , Dobramento de Proteína , Streptomyces/química , Streptomyces/genética , Streptomyces/metabolismo
16.
MethodsX ; 6: 1933-1943, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31660296

RESUMO

The Shanghai Advanced Proton Therapy facility (SAPT) is a hospital-based facility that began construction in December of 2014 with commissioning of the first scanned proton beam line starting in October of 2017. Proton beams are extracted from a synchrotron accelerator with energies between 70 and 235 MeV. Beam delivery uses the modulated scanning and energy stacking techniques to produce a maximal scanning area of 40 × 30 cm2 at the iso-center. Prior to clinical use, the beam delivery system was characterized and calibrated following the guidelines of the IEC 62667 medical electronic equipment standard including the spot size in air, spot position, depth dose distributions, and lateral dose profiles, as well as the beam monitor calibrations following the IAEA TRS-398 recommendations with small differences. •The measured dosimetric results showed that the full width at half maximum (FWHM) for the beam spot size in air varied approximately from 6 mm to 13 mm. The dose fall-off (DDF) derived from the measured depth dose in water varied from 4.7 mm at 235 MeV to 0.7 mm at 70 MeV. The homogeneity of the scanned field was better than 2% for various energies as expected.•Furthermore, the beam reproducibility and proportionality delivery accuracy was also stable with the results better than 0.1% and 1% respectively. Finally, the dose monitor calibration factor, its reproducibility and stability were tested. Reproducibility tests exhibited a standard deviation (SD) result of less than 1% during the test period.•All the measured dosimetric parameters showed that the design specifications were well achieved and the results are suitable for being used as a part of the clinical commissioning and quality assurance program for treating patients.

17.
Opt Express ; 27(16): 22890-22897, 2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31510573

RESUMO

The phenomenon of vortex beams passing through a diffraction plate with rotationally symmetric superposition of spiral pinholes array is investigated. The variations of the topological charges of vortex beams are theoretically analyzed, numerically simulated and experimentally observed. It proves that the obtained topological charge value (l) is a combination of that of incident beam (l0) and the number of the spiral structures (m). The relationship is l = Mm-l0, where M is an integer. With this study, we proved that spiral transmission structures can also achieve the variations of the topological charge of a vortex beam. And this method is simple and costless. With the advantages of this method, it might have important applications in optical communications and optical tweezers.

18.
Toxins (Basel) ; 11(10)2019 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-31547007

RESUMO

Biodegradation is efficient for removing cyanobacterial toxins, such as microcystins (MCs) and nodularin (NOD). However, not all the microbial strains with the microcystin-biodegrading enzymes MlrA and MlrC could biodegrade NOD. Studies on genes and enzymes for biodegrading NOD can reveal the function and the biodegradation pathway of NOD. Based on successful cloning and expression of the USTB-05-A and USTB-05-C genes from Sphingopyxis sp. USTB-05, which are responsible for the biodegradation of MCs, the pathway for biodegrading NOD by these two enzymes was investigated in this study. The findings showed that the enzyme USTB-05-A converted cyclic NOD (m/z 825.4516) into its linear type as the first product by hydrolyzing the arginine and Adda peptide bond, and that USTB-05-C cut off the Adda and glutamic acid peptide bond of linearized NOD (m/z 843.4616) and produced dimeric Adda (m/z 663.4377) as the second product. Further, based on the homology modeling of enzyme USTB-05-A, site-directed mutants of USTB-05-A were constructed and seven crucial sites for enzyme USTB-05-A activity were found. A complete enzymatic mechanism for NOD biodegradation by USTB-05-A in the first step was proposed: glutamic acid 172 and histidine 205 activate a water molecule facilitating a nucleophilic attack on the arginine and Adda peptide bond of NOD; tryptophan 176 and tryptophan 201 contact the carboxylate side chain of glutamic acid 172 and accelerate the reaction rates; and histidine 260 and asparagine 264 function as an oxyanion hole to stabilize the transition states.

19.
Chem Commun (Camb) ; 55(79): 11856-11859, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31528906

RESUMO

A supramolecular shape memory hydrogel (SMH) with monitorable shape memory performance both in macro and microscopic scales was prepared through a combination of pH-responsive fluorescent carbon nanoparticles, polyvinyl alcohol and cross-linked polyacrylamide. The investigation of our SMH will provide a good understanding of the shape memory mechanism and guide in the structure design of the novel SMH.

20.
ACS Omega ; 4(9): 13772-13781, 2019 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-31497695

RESUMO

The partitioning of compounds between aqueous and other phases is important for predicting toxicity. Although thousands of octanol-water partition coefficients have been measured, these represent only a small fraction of the anthropogenic compounds present in the environment. The octanol phase is often taken to be a mimic of the inner parts of phospholipid membranes. However, the core of such membranes is typically more hydrophobic than octanol, and other partition coefficients with other compounds may give complementary information. Although a number of (cheap) empirical methods exist to compute octanol-water (log k OW) and hexadecane-water (log k HW) partition coefficients, it would be interesting to know whether physics-based models can predict these crucial values more accurately. Here, we have computed log k OW and log k HW for 133 compounds from seven different pollutant categories as well as a control group using the solvation model based on electronic density (SMD) protocol based on Hartree-Fock (HF) or density functional theory (DFT) and the COSMO-RS method. For comparison, XlogP3 (log k OW) values were retrieved from the PubChem database, and KowWin log k OW values were determined as well. For 24 of these compounds, log k OW was computed using potential of mean force (PMF) calculations based on classical molecular dynamics simulations. A comparison of the accuracy of the methods shows that COSMO-RS, KowWin, and XlogP3 all have a root-mean-square deviation (rmsd) from the experimental data of ≈0.4 log units, whereas the SMD protocol has an rmsd of 1.0 log units using HF and 0.9 using DFT. PMF calculations yield the poorest accuracy (rmsd = 1.1 log units). Thirty-six out of 133 calculations are for compounds without known log k OW, and for these, we provide what we consider a robust prediction, in the sense that there are few outliers, by averaging over the methods. The results supplied may be instrumental when developing new methods in computational ecotoxicity. The log k HW values are found to be strongly correlated to log k OW for most compounds.

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