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Protein post-translational modifications (PTMs) with various acyl groups play central roles in Streptomyces. But whether these acyl groups can be further modified, and the influences of these potential modifications on bacterial physiology have not been addressed. Here in Streptomyces roseosporus with rich crotonylation, a luciferase monooxygenase LimB is identified to elaborately regulate the crotonylation level, morphological development and antibiotic production by oxidation on the crotonyl groups of an acetyl-CoA synthetase Acs. This chemical modification on crotonylation leads to Acs degradation via the protease ClpP1/2 pathway and lowered intracellular crotonyl-CoA pool. Thus, we show that acyl groups after PTMs can be further modified, herein named post-PTM modification (PPM), and LimB is a PTM modifier to control the substrate protein turnover for cell development of Streptomyces. These findings expand our understanding of the complexity of chemical modifications on proteins for physiological regulation, and also suggest that PPM would be widespread. Protein crotonylation, as one of post-translational modifications (PTMs), can be further modified, herein named post-PTM (PPM) by a monooxygenase in Streptomyces to regulate substrate protein turnover and cell physiology. [ABSTRACT FROM AUTHOR]

The beneficial effects attributed to Bifidobacterium are largely attributed to their immunomodulatory capabilities, which are likely to be species- and even strain-specific. However, their strain-specificity in direct and indirect immune modulation remain largely uncharacterized. We have shown that B. pseudolongum UMB-MBP-01, a murine isolate strain, is capable of suppressing inflammation and reducing fibrosis in vivo. To ascertain the mechanism driving this activity and to determine if it is specific to UMB-MBP-01, we compared it to a porcine tropic strain B. pseudolongum ATCC25526 using a combination of cell culture and in vivo experimentation and comparative genomics approaches. Despite many shared features, we demonstrate that these two strains possess distinct genetic repertoires in carbohydrate assimilation, differential activation signatures and cytokine responses signatures in innate immune cells, and differential effects on lymph node morphology with unique local and systemic leukocyte distribution. Importantly, the administration of each B. pseudolongum strain resulted in major divergence in the structure, composition, and function of gut microbiota. This was accompanied by markedly different changes in intestinal transcriptional activities, suggesting strain-specific modulation of the endogenous gut microbiota as a key to immune modulatory host responses. Our study demonstrated a single probiotic strain can influence local, regional, and systemic immunity through both innate and adaptive pathways in a strain-specific manner. It highlights the importance to investigate both the endogenous gut microbiome and the intestinal responses in response to probiotic supplementation, which underpins the mechanisms through which the probiotic strains drive the strain-specific effect to impact health outcomes. [ABSTRACT FROM AUTHOR]

The beneficial effects attributed to Bifidobacterium are largely attributed to their immunomodulatory capabilities, which are likely to be species- and even strain-specific. However, their strain-specificity in direct and indirect immune modulation remain largely uncharacterized. We have shown that B. pseudolongum UMB-MBP-01, a murine isolate strain, is capable of suppressing inflammation and reducing fibrosis in vivo. To ascertain the mechanism driving this activity and to determine if it is specific to UMB-MBP-01, we compared it to a porcine tropic strain B. pseudolongum ATCC25526 using a combination of cell culture and in vivo experimentation and comparative genomics approaches. Despite many shared features, we demonstrate that these two strains possess distinct genetic repertoires in carbohydrate assimilation, differential activation signatures and cytokine responses signatures in innate immune cells, and differential effects on lymph node morphology with unique local and systemic leukocyte distribution. Importantly, the administration of each B. pseudolongum strain resulted in major divergence in the structure, composition, and function of gut microbiota. This was accompanied by markedly different changes in intestinal transcriptional activities, suggesting strain-specific modulation of the endogenous gut microbiota as a key to immune modulatory host responses. Our study demonstrated a single probiotic strain can influence local, regional, and systemic immunity through both innate and adaptive pathways in a strain-specific manner. It highlights the importance to investigate both the endogenous gut microbiome and the intestinal responses in response to probiotic supplementation, which underpins the mechanisms through which the probiotic strains drive the strain-specific effect to impact health outcomes. [ABSTRACT FROM AUTHOR]

An X-band reflectarray antenna using 16 × 12 double square ring elements for satellite communications is proposed in this paper. The feed is a 4 × 3 elements microstrip patch array designed to create edge taper of approximately − 10 dB. A prototype with right-hand circular polarization (RHCP) is manufactured and tested, and the good agreements between simulations and measurements are demonstrated. The good performance is obtained with the aperture efficiency of 40.7% and the 3-dB gain bandwidth of about 10% which is beneficial to nanosatellites. [ABSTRACT FROM AUTHOR]

The effects of thermal treatment on the pore structure and mechanical property evolution of granite were experimentally investigated to evaluate the risks of traditional and critical geothermal systems. The microstructure of thermally treated granite was studied using an optical microscope and nuclear magnetic resonance, and the mechanical properties of thermally treated granite were studied under uniaxial compression. X-ray diffraction results showed that the mineralogical phase of granite hardly changed during thermal treatment from room temperature to 800 °C, but the granite experienced first a decrease and then an increase in porosity. Although overall porosity decreased at 200 °C, the proportion of pore throat radium beyond 6.3 μm grew increasingly with the treatment temperature, facilitating advective heat transport in the geothermal system. Intergranular microcracks caused by thermal anisotropic properties started at below 400 °C, and transgranular microcracks first appeared in feldspar at around 400 °C, finally extending to quartz at around 600 °C. The granite was strengthened due to decreased porosity at around 200 °C. Then, the granite was weakened and the failure transited from brittle to ductile due to increased porosity, where a sharp reduction occurred at 400–600 °C for α-β transition of quartz. The change in strength by cyclic heating under 200 °C was unnoticeable for temperature memory effect, but the cumulative strain at peak stress increased with the number of heating cycles. The changes in the pore and mechanical properties caused by thermal treatment favour geothermal systems which are not within the tectonic zone. However, increased porosity and strength weakening destabilize nearby faults due to normal stress release and strength weakening. [ABSTRACT FROM AUTHOR]

The original article can be found online at https://doi.org/10.1038/s41598-023-27706-0. Correction to: I Scientific Reports i https://doi.org/10.1038/s41598-023-27706-0, published online 19 January 2023 The original version of this Article contained an error in the spelling of the author Jegan Iyyathurai which was incorrectly given as Jegan Lyyathurai. [Extracted from the article]

For many advanced applications, high thermal stability above 400 °C remains as a challenge for the ordered mesoporous titania films. In this work, we attempt to increase the thermal stability of mesoporous structure in titania film crystallization via PS- b-PEO block copolymer templating route. This paper reports the highly crystallized mesoporous titania film on silicon substrate thermally stable at 600 °C. The photocatalytic activity of the titania mesoporous film was also shown to be twice of that templated by F127 for degradation of methylene blue (MB). The present results also indicate that at low crystallinity, photocatalytic activity is controlled primarily by crystal perfection rather that surface area. [ABSTRACT FROM AUTHOR]

In the framework of Regge phenomenology, the masses of the charmed states cq̄ (q=u,d,s) lying on the 13S1-like trajectories are estimated. The overall agreement between our estimated masses and the recent predictions given using modified quark models by Matsuki et al., Lakhina et al. and Close et al. is good. The masses of the observed charmed states Ds0(2317), DsJ(2860) and DsJ(2690)/DsJ(2700) can reasonably be reproduced in the picture of these charmed states as simple quark–antiquark configurations. We therefore suggest that Ds0(2317) can be identified with the cs̄(13P0) states. The possible assignments of the DsJ(2860) and DsJ(2690)/DsJ(2700) are discussed. [ABSTRACT FROM AUTHOR]

The vaginal microbiota is thought to play a role in modulating risk of high-risk human papillomavirus (hrHPV) infection. We examined the relationship between the vaginal microbiota and persistent hrHPV infection in HIV-negative and HIV-positive women. We used 16S-rRNA sequencing to characterize the vaginal microbiota of two serial samples taken six months apart from 211 Nigerian women (67%, 142/211 HIV-positive and 33%, 69/211 HIV-negative) and evaluated the association between the vaginal microbiota and persistent hrHPV infection using generalized estimating equation logistic regression models and linear discriminant analysis effect size (LEfSe) algorithm to identify phylotypic biomarkers of persistent hrHPV infection. The high diversity microbiota, Community State Type IV-B, was the most prevalent in both HIV-negative (38% at baseline, 30% at the follow-up visit) and HIV-positive (27% at baseline, 35% at the follow-up visit) women. The relationship between the vaginal microbiota and persistent hrHPV was modified by HIV status. In HIV-negative women, women with Lactobacillus dominant microbiota had lower odds (OR: 0.35, 95% CI 0.14–0.89, p = 0.03) of persistent hrHPV compared to women with Lactobacillus deficient microbiota. While among HIV-positive women, the odds of being persistently infected with hrHPV was higher in women with Lactobacillus dominant microbiota (OR: 1.25, 95% CI 0.73–2.14 p = 0.41). This difference in effect estimates by HIV was statistically significant (p = 0.02). A high diversity vaginal microbial community with paucity of Lactobacillus species was associated with persistent hrHPV infection in HIV-negative women but not in HIV-positive women. [ABSTRACT FROM AUTHOR]

A Lactobacillus-deficient, anaerobe-rich vaginal microbiome has been associated with local inflammation and spontaneous preterm birth (sPTB), but few studies have assessed this association in the setting of HIV. We performed metagenomic sequencing and inflammatory marker assays on vaginal swabs collected in pregnancy. We grouped samples into 7 metagenomic clusters (mgClust) using the non-redundant VIRGO catalogue, and derived inflammatory scores by factor analysis. Of 221 participants, median Shannon diversity index (SDI) was highest in HIV+ with detectable viral load (1.31, IQR: 0.85–1.66; p < 0.001) and HIV+ with undetectable virus (1.17, IQR: 0.51–1.66; p = 0.01) compared to HIV− (0.74, IQR: 0.35–1.26). Inflammatory scores positively correlated with SDI (+ 0.66, 95%CI 0.28, 1.03; p = 0.001), highest among anaerobe-rich mgClust2–mgClust6. HIV was associated with predominance of anaerobe-rich mgClust5 (17% vs. 6%; p = 0.02) and mgClust6 (27% vs. 11%; p = 0.002). Relative abundance of a novel Gardnerella metagenomic subspecies > 50% predicted sPTB (RR 2.6; 95%CI: 1.1, 6.4) and was higher in HIV+ (23% vs. 10%; p = 0.001). A novel Gardnerella metagenomic subspecies more abundant in women with HIV predicted sPTB. The risk of sPTB among women with HIV may be mediated by the vaginal microbiome and inflammation, suggesting potential targets for prevention. [ABSTRACT FROM AUTHOR]

Xanthine oxidase (XOD) catalyzes the metabolism of hypoxanthine and xanthine to uric acid, the overproduction of which could cause hyperuricemia, a risk factor for gout. Inhibition of XOD is a major treatment for gout, and biflavonoids have been found to act as XOD-inhibitory compounds. In this study, ultrafiltration liquid chromatography with photodiode-array detection coupled to electrospray-ionization tandem mass spectrometry (UF-LC-PDA-ESI-MS) was used to screen and identify XOD inhibitors from S. tamariscina. High-performance counter-current chromatography (HPCCC) was used to separate and isolate the active constituents of these XOD inhibitors. Furthermore, ultrahigh-performance liquid chromatography (UPLC) and triple-quadrupole mass spectrometry (TQ-MS) was used to determine the XOD-inhibitory activity of the obtained XOD inhibitors, and enzyme kinetics was performed with Lineweaver-Burk (LB) plots using xanthine as the substrate. As a result, two compounds in S. tamariscina were screened as XOD inhibitors: 65.31 mg amentoflavone and 0.76 mg robustaflavone were isolated from approximately 2.5 g S. tamariscina by use of HPCCC. The purities of the two compounds obtained were over 98 % and 95 %, respectively, as determined by high-performance liquid chromatography (HPLC). Lineweaver-Burk plot analysis indicated that amentoflavone and robustaflavone were non-competitive inhibitors of XOD, and the IC values of amentoflavone and robustaflavone for XOD inhibition were 16.26 μg mL (30.22 μmol L) and 11.98 μg mL (22.27 μmol L), respectively. The IC value of allopurinol, used as the standard, was 7.49 μg mL (46.23 μmol L). The results reveal that the method for systematic screening, identification, and isolation of bioactive components in S. tamariscina and for detecting their inhibitory activity using ultrafiltration LC-ESI-MS, HPCCC, and UPLC-TQ-MS is feasible and efficient, and could be expected to extend to screening and separation of other enzyme inhibitors. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

A quantificational method for 7 phthalate esters in non-alcoholic beverages was developed. Dimethyl phthalate, di-ethyl phthalate, di-propyl phthalate (DPP), di-butyl phthalate (DBP), benzyl butyl phthalate, di-(2-ethylhexyl) phthalate (DEHP), and di-octyl phthalate (DOP) were extracted from non-alcoholic beverages with the optimized solid-phase extraction method, and quantification was achieved by gas chromatography-mass spectrometry with isotope internal standard of d-di-(2-ethylhexyl) phthalate (DEHP-d). The inter-day method repeatability (RSD) was 8-13 %, whereas the intra-day method repeatability (RSD) was 9-15 %. The mean spiking recoveries were 84-105 %. A wide variety of phthalate concentrations was observed in 48 non-alcoholic beverages. DEHP was the most abundant phthalate compound followed by DBP, DPP, and DOP. DEHP was found in sport drinks (0.015-0.098 mg L), tea (0.016-0.123 mg L), coffee (0.028-0.159 mg L), and fruit juices (0.022-0.126 mg L). [ABSTRACT FROM AUTHOR]