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1.
Skin Res Technol ; 30(7): e13824, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38978223

RESUMEN

BACKGROUND: Methods available at home for capturing facial images to track changes in skin quality and evaluate skincare treatments are limited. In this study, we developed a smartphone camera application (app) for personalized facial aesthetic monitoring. MATERIALS AND METHODS: A face alignment indicators (FAIN) system utilizing facial landmark detection, an artificial intelligence technique, to estimate key facial parts, was implemented into the app to maintain a consistent facial appearance during image capture. The FAIN system is composed of a fixed target indicator and an alignment indicator that dynamically changes its shape according to the user's face position, size, and orientation. Users align their faces to match the alignment indicator with the fixed target indicator, and the image is automatically captured when alignment is achieved. RESULTS: We investigated the app's effectiveness in ensuring a consistent facial appearance by analyzing both geometric and colorimetric data. Geometric information from captured faces and colorimetric data from stickers applied to the faces were utilized. The coefficients of variation (CVs) for the L*, a*, and b* values of the stickers were higher compared to those measured by a colorimeter, with CVs of 14.9 times, 8.14 times, and 4.41 times for L*, a*, and b*, respectively. To assess the feasibility of the app for facial aesthetic monitoring, we tracked changes in pseudo-skin color on the cheek of a participant using skin-colored stickers. As a result, we observed the smallest color difference ∆Eab of 1.901, which can be considered as the experimentally validated detection limit using images acquired by the app. CONCLUSION: While the current monitoring method is a relative quantification approach, it contributes to evidence-based evaluations of skincare treatments.


Asunto(s)
Estética , Cara , Aplicaciones Móviles , Teléfono Inteligente , Humanos , Cara/anatomía & histología , Cara/diagnóstico por imagen , Femenino , Colorimetría/instrumentación , Colorimetría/métodos , Fotograbar , Adulto , Masculino , Inteligencia Artificial
2.
Protein Expr Purif ; 219: 106487, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38657915

RESUMEN

The bacterial Efe system functions as an importer of free Fe2+ into cells independently of iron-chelating compounds such as siderophores and consisted of iron-binding protein EfeO, peroxidase EfeB, and transmembrane permease EfeU. While we and other researchers reported crystal structures of EfeO and EfeB, that of EfeU remains undetermined. In this study, we constructed expression system of EfeU derived from Escherichia coli, selected E. coli Rosetta-gami 2 (DE3) as an expression host, and succeeded in purification of the proteins which were indicated to form an oligomer by blue native PAGE. We obtained preliminary data of the X-ray crystallography, suggesting that expression and purification methods we established in this study enable structural analysis of the bacterial Efe system.


Asunto(s)
Proteínas de Escherichia coli , Escherichia coli , Hierro , Escherichia coli/genética , Escherichia coli/metabolismo , Cristalografía por Rayos X , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/química , Proteínas de Escherichia coli/metabolismo , Proteínas de Escherichia coli/aislamiento & purificación , Hierro/metabolismo , Hierro/química , Expresión Génica , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/aislamiento & purificación , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/biosíntesis , Proteínas de Unión a Hierro/química , Proteínas de Unión a Hierro/genética , Proteínas de Unión a Hierro/aislamiento & purificación , Proteínas de Unión a Hierro/metabolismo
3.
Future Oncol ; 20(11): 679-690, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38131189

RESUMEN

Aim: This study estimated the incidence of moderate-to-severe drug-induced interstitial lung disease (ILD) among patients with breast cancer in Japan. Methods: We analyzed a large nationwide database of patients with breast cancer treated with anticancer therapies between 2009 and 2022. ILD was identified using diagnostic codes and treatment records. Results: Of the 81,601 patients, 1042 developed ILD requiring corticosteroids, corresponding to an incidence rate of 1.41 per 100 person-years. The incidence varied across years and treatment regimens. Most ILD incidents occurred within the initial 90-day period post-anticancer therapy initiation. Conclusion: Increase in ILD cases and potential risk variations among treatments underline the importance of continued monitoring, especially during treatment onset, and ILD management in patients with breast cancer undergoing therapy.


This article investigates how often a lung condition known as interstitial lung disease (ILD) occurs in patients treated for breast cancer in Japan. ILD can cause inflammation and damage to the lungs and can be a side effect of some cancer treatments. The study looked at over 81,000 patients with breast cancer from 2009 to 2022. A total of 1042 patients developed ILD that required treatment with steroids to reduce inflammation. This number suggests that ILD occurred in 1.41 out of every 100 patients treated each year. The study noted that the chances of developing ILD varied over the years and depended on the type of cancer treatment. The findings showed that ILD is a risk factor for patients undergoing breast cancer treatment, and the risk can change depending on the treatment they receive. This highlights the importance of doctors keeping a close eye on their patients, especially early in the treatment process, to identify and manage any signs of ILD. Careful monitoring can help improve the health and treatment outcomes of patients with breast cancer. The study also points to the need for more research to understand why ILD occurs and how to prevent or treat it.


Asunto(s)
Neoplasias de la Mama , Carcinoma de Pulmón de Células no Pequeñas , Enfermedades Pulmonares Intersticiales , Neoplasias Pulmonares , Humanos , Femenino , Incidencia , Neoplasias de la Mama/complicaciones , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/epidemiología , Japón/epidemiología , Factores de Riesgo , Enfermedades Pulmonares Intersticiales/epidemiología , Enfermedades Pulmonares Intersticiales/etiología , Enfermedades Pulmonares Intersticiales/terapia , Estudios Retrospectivos
5.
Sci Rep ; 13(1): 9279, 2023 06 20.
Artículo en Inglés | MEDLINE | ID: mdl-37340058

RESUMEN

Saccharomyces cerevisiae, an essential player in alcoholic fermentation during winemaking, is rarely found in intact grapes. Although grape-skin environment is unsuitable for S. cerevisiae's stable residence, Saccharomycetaceae-family fermentative yeasts can increase population on grape berries after colonization during raisin production. Here, we addressed adaptation of S. cerevisiae to grape-skin ecosystem. The yeast-like fungus Aureobasidium pullulans, a major grape-skin resident, exhibited broad spectrum assimilation of plant-derived carbon sources, including ω-hydroxy fatty acid, arising from degradation of plant cuticles. In fact, A. pullulans encoded and secreted possible cutinase-like esterase for cuticle degradation. When intact grape berries were used as a sole carbon source, such grape-skin associated fungi increased the accessibility to fermentable sugars by degrading and assimilating the plant cell wall and cuticle compounds. Their ability seems also helpful for S. cerevisiae to obtain energy through alcoholic fermentation. Thus, degradation and utilization of grape-skin materials by resident microbiota may account for their residence on grape-skin and S. cerevisiae's possible commensal behaviors. Conclusively, this study focused on the symbiosis between grape-skin microbiota and S. cerevisiae from the perspective of winemaking origin. Such plant-microbe symbiotic interaction may be a prerequisite for triggering spontaneous food fermentation.


Asunto(s)
Vitis , Vino , Saccharomyces cerevisiae/metabolismo , Vitis/microbiología , Ecosistema , Vino/análisis , Hongos
6.
Diagnostics (Basel) ; 13(11)2023 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-37296821

RESUMEN

Tooth shade determination methods for evaluating the effectiveness of whitening products at home are limited. In this study, an iPhone app for personalized tooth shade determination was developed. While capturing dental photographs in selfie mode before and after whitening, the app can maintain consistent illumination and tooth appearance conditions that affect tooth color measurement. An ambient light sensor was used to standardize the illumination conditions. To maintain consistent tooth appearance conditions determined by appropriately opening the mouth, facial landmark detection, an artificial intelligence technique that estimates key face parts and outlines, was used. The effectiveness of the app in ensuring uniform tooth appearance was investigated through color measurements of the upper incisors of seven participants via photographs captured in succession. The coefficients of variation for incisors L*, a*, and b* were less than 0.0256 (95% CI, 0.0173-0.0338), 0.2748 (0.1596-0.3899), and 0.1053 (0.0078-0.2028), respectively. To examine the feasibility of the app for tooth shade determination, gel whitening after pseudo-staining by coffee and grape juice was performed. Consequently, whitening results were evaluated by monitoring the ∆Eab color difference values (1.3 unit minimum). Although tooth shade determination remains a relative quantification method, the proposed method can support evidence-based selection of whitening products.

7.
J Appl Glycosci (1999) ; 70(4): 99-107, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38239764

RESUMEN

Some probiotics including lactobacilli, colonize host animal cells by targeting glycosaminoglycans (GAGs), such as heparin, located in the extracellular matrix. Recent studies have shown that several lactic acid bacteria degrade GAGs. Here we show the structure/function relationship of Lacticaseibacillus rhamnosus 4-deoxy-L-threo-5-hexosulose-uronate ketol-isomerase (KduI) crucial for metabolism of unsaturated glucuronic acid produced through degradation of GAGs. Crystal structures of ligand-free and bound KduIs were determined by X-ray crystallography and the enzyme was found to consist of six identical subunits and adopt a ß-helix as a basic scaffold. Ligands structurally similar to the substrate were bound to the cleft of each enzyme subunit. Several residues located in the cleft interacted with ligands through hydrogen bonds and/or C-C contacts. In addition to substrate analogs, a metal ion coordinated to four residues, His198, His200, Glu205, and His248, in the cleft, and the enzyme activity was significantly inhibited by a chelator, ethylenediaminetetraacetic acid. Site-directed mutants in Arg163, Ile165, Thr184, Thr194, His200, Arg203, Tyr207, Met262, and Tyr269 in the cleft exhibited little enzyme activity, indicating that these residues and the metal ion constituted an active site in the cleft. This is the first report on the active site structure of KduI based on the ligand-bound complex.

8.
Proc Jpn Acad Ser B Phys Biol Sci ; 98(10): 529-552, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36504195

RESUMEN

A bacterium with a "mouth"-like pit structure isolated for the first time in the history of microbiology was a Gram-negative rod, containing glycosphingolipids in the cell envelope, and named Sphingomonas sp. strain A1. The pit was dynamic, with repetitive opening and closing during growth on alginate, and directly included alginate concentrated around the pit, particularly by flagellins, an alginate-binding protein localized on the cell surface. Alginate incorporated into the periplasm was subsequently transferred to the cytoplasm by cooperative interactions of periplasmic solute-binding proteins and an ATP-binding cassette transporter in the cytoplasmic membrane. The mechanisms of assembly, functions, and interactions between the above-mentioned molecules were clarified using structural biology. The pit was transplanted into other strains of sphingomonads, and the pitted recombinant cells were effectively applied to the production of bioethanol, bioremediation for dioxin removal, and other tasks. Studies of the function of the pit shed light on the biological significance of cell surface structures and macromolecule transport in bacteria.


Asunto(s)
Bacterias , Cara , Membrana Celular
9.
Sci Rep ; 12(1): 12653, 2022 07 25.
Artículo en Inglés | MEDLINE | ID: mdl-35879323

RESUMEN

Gram-negative Sphingomonas sp. strain A1 exhibits positive chemotaxis toward acidic polysaccharide pectin. SPH1118 has been identified as a pectin-binding protein involved in both pectin chemotaxis and assimilation. Here we show tertiary structures of SPH1118 with six different conformations as determined by X-ray crystallography. SPH1118 consisted of two domains with a large cleft between the domains and substrates bound to positively charged and aromatic residues in the cleft through hydrogen bond and stacking interactions. Substrate-free SPH1118 adopted three different conformations in the open form. On the other hand, the two domains were closed in substrate-bound form and the domain closure ratio was changed in response to the substrate size, suggesting that the conformational change upon binding to the substrate triggered the expression of pectin chemotaxis and assimilation. This study first clarified that the solute-binding protein with dual functions recognized the substrate through flexible conformational changes in response to the substrate size.


Asunto(s)
Quimiotaxis , Sphingomonas , Proteínas Bacterianas/metabolismo , Sitios de Unión , Proteínas Portadoras/metabolismo , Cristalografía por Rayos X , Modelos Moleculares , Pectinas/metabolismo , Conformación Proteica , Sphingomonas/metabolismo , Especificidad por Sustrato
10.
Sci Rep ; 12(1): 8032, 2022 06 07.
Artículo en Inglés | MEDLINE | ID: mdl-35672418

RESUMEN

While biodiesel is drawing attention as an eco-friendly fuel, the use of crude glycerol, a byproduct of the fuel production process, has increasingly become a concern to be addressed. Here we show the development of a low-cost fermentation technology using an atmospheric nitrogen-fixing bacterium to recycle crude glycerol into functional biopolymers. Azotobacter vinelandii showed substantial growth on tap water-diluted crude glycerol without any pretreatment. The number of viable A. vinelandii cells increased over 1000-fold under optimal growth conditions. Most of the glycerol content (~ 0.2%) in the crude glycerol medium was completely depleted within 48 h of culture. Useful polymers, such as polyhydroxybutyrate and alginate, were also produced. Polyhydroxybutyrate productivity was increased ten-fold by blocking the alginate synthesis pathway. Although there are few examples of using crude glycerol directly as a carbon source for microbial fermentation, there are no reports on the use of crude glycerol without the addition of a nitrogen source. This study demonstrated that it is possible to develop a technology to produce industrially useful polymers from crude glycerol through energy-saving and energy-efficient fermentation using the atmospheric nitrogen-fixing microorganism A. vinelandii.


Asunto(s)
Azotobacter vinelandii , Alginatos/metabolismo , Azotobacter vinelandii/metabolismo , Fermentación , Glicerol/metabolismo , Nitrógeno/metabolismo , Polímeros/metabolismo
11.
Sci Rep ; 12(1): 10948, 2022 06 29.
Artículo en Inglés | MEDLINE | ID: mdl-35768476

RESUMEN

Host determinants for formation/composition of human oral microbiota remain to be clarified, although microorganisms entering the mouth cannot necessarily colonize the oral environment. Here we show that human oral-abundant bacteria degraded host glycosaminoglycans (GAGs) in saliva and gingiva, and certain bacteria significantly grew on hyaluronan (HA), a kind of GAGs. Microbial communities from teeth or gingiva of healthy donors assimilated HA. Metagenomic analysis of human oral microbiota under different carbon sources revealed HA-driven Granulicatella growth. HA-degrading bacterial strains independently isolated from teeth and gingiva were identified as Granulicatella adiacens producing extracellular 130 kDa polysaccharide lyase as a HA-degrading enzyme encoded in a peculiar GAG genetic cluster containing genes for isomerase KduI and dehydrogenase DhuD. These findings demonstrated that GAGs are one of the host determinants for formation/composition of oral microbiota not only for colonization but also for the adaptation to the host niche. Especially, HA enhanced the G. adiacens propagation.


Asunto(s)
Carnobacteriaceae , Microbiota , Bacterias/metabolismo , Carnobacteriaceae/metabolismo , Glicosaminoglicanos/metabolismo , Humanos , Ácido Hialurónico/metabolismo , Streptococcus/metabolismo
12.
Molecules ; 27(2)2022 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-35056653

RESUMEN

4-Deoxy-l-erythro-5-hexoseulose uronate (DEH), DEH reductase, and alginate lyase have key roles in the metabolism of alginate, a promising carbon source in brown macroalgae for biorefinery. In contrast to the widely reviewed alginate lyase, DEH and DEH reductase have not been previously reviewed. Here, we summarize the current understanding of DEH and DEH reductase, with emphasis on (i) the non-enzymatic and enzymatic formation and structure of DEH and its reactivity to specific amino groups, (ii) the molecular identification, classification, function, and structure, as well as the structural determinants for coenzyme specificity of DEH reductase, and (iii) the significance of DEH for biorefinery. Improved understanding of this and related fields should lead to the practical utilization of alginate for biorefinery.


Asunto(s)
Alginatos/metabolismo , Ácidos Hexurónicos/metabolismo , Oxidorreductasas/metabolismo
13.
Biochem Biophys Res Commun ; 594: 124-130, 2022 02 26.
Artículo en Inglés | MEDLINE | ID: mdl-35081501

RESUMEN

EfeUOB is a siderophore-independent iron uptake mechanism in bacteria. EfeU, EfeO, and EfeB are a permease, an iron-binding or electron-transfer protein, and a peroxidase, respectively. A Gram-negative bacterium, Sphingomonas sp. strain A1, encodes EfeU, EfeO, EfeB together with alginate-binding protein Algp7, a truncated EfeO-like protein (EfeOII), in the genome. The typical EfeO (EfeOI) consists of N-terminal cupredoxin and C-terminal M75 peptidase domains. Here, we detail the structure and function of bacterial EfeB and EfeO. Crystal structures of strain A1 EfeB and Escherichia coli EfeOI were determined at 2.30 Å and 1.85 Å resolutions, respectively. A molecule of heme involved in oxidase activity was bound to the C-terminal Dyp peroxidase domain of EfeB. Two domains of EfeOI were connected by a short loop, and a zinc ion was bound to four residues, Glu156, Glu159, Asp173, and Glu255, in the C-terminal M75 peptidase domain. These residues formed tetrahedron geometry suitable for metal binding and are well conserved among various EfeO proteins including Algp7 (EfeOII), although the metal-binding site (HxxE) is proposed in the C-terminal M75 peptidase domain. This is the first report on structure of a typical EfeO with two domains, postulating a novel metal-binding motif "ExxE-//-D-//-E" in the EfeO C-terminal M75 peptidase domain.


Asunto(s)
Proteínas de Transporte de Catión/química , Proteínas de Escherichia coli/química , Hemo/química , Hierro/química , Secuencias de Aminoácidos , Azurina/química , Proteínas Bacterianas/química , Proteínas Bacterianas/metabolismo , Sitios de Unión , Transporte Biológico , Cristalografía por Rayos X , Proteínas de Escherichia coli/metabolismo , Metales/química , Conformación Molecular , Oxidorreductasas/química , Unión Proteica , Conformación Proteica , Dominios Proteicos , Estructura Secundaria de Proteína , Sphingomonas/metabolismo
14.
Biosci Biotechnol Biochem ; 85(12): 2410-2419, 2021 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-34610097

RESUMEN

Gram-negative Sphingomonas sp. A1 incorporates acidic polysaccharide alginate into the cytoplasm via a cell-surface alginate-binding protein (AlgQ2)-dependent ATP-binding cassette transporter (AlgM1M2SS). We investigated the function of calcium bound to the EF-hand-like motif in AlgQ2 by introducing mutations at the calcium-binding site. The X-ray crystallography of the AlgQ2 mutant (D179A/E180A) demonstrated the absence of calcium binding and significant disorder of the EF-hand-like motif. Distinct from the wild-type AlgQ2, the mutant was quite unstable at temperature of strain A1 growth, although unsaturated alginate oligosaccharides stabilized the mutant by formation of substrate/protein complex. In the assay of ATPase and alginate transport by AlgM1M2SS reconstructed in the liposome, the wild-type and mutant AlgQ2 induced AlgM1M2SS ATPase activity in the presence of unsaturated alginate tetrasaccharide. These results indicate that the calcium bound to EF-hand-like motif stabilizes the substrate-unbound AlgQ2 but is not required for the complexation of substrate-bound AlgQ2 and AlgM1M2SS.


Asunto(s)
Proteínas Bacterianas
15.
J Biosci Bioeng ; 132(4): 321-326, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34176737

RESUMEN

The black koji mold, Aspergillus luchuensis, which belongs to Aspergillus section Nigri, is used for the production of traditional Japanese spirits (shochu) mainly in the southern districts of Japan. This mold is known to produce amylolytic enzymes essential for shochu production; however, mechanisms regulating amylolytic gene expression in A. luchuensis have not been studied in as much detail as those in the yellow koji mold, Aspergillus oryzae. Here, we examined the gene expression profiles of deletion mutants of transcription factors orthologous to A. oryzae AmyR and CreA in A. luchuensis. A. luchuensis produces acid-unstable (AmyA) and acid-stable (AsaA) α-amylases. AmyA production and amyA gene expression were not influenced by amyR or creA deletion, indicating that amyA was constitutively expressed. In contrast, asaA gene expression was significantly down- and upregulated upon deletion of amyR and creA, respectively. Furthermore, the glaA and agdA genes (encoding glucoamylase and α-glucosidase, respectively) showed expression profiles similar to those of asaA. Thus, genes that play pivotal roles in starch saccharification, asaA, glaA, and agdA, were found to be regulated by AmyR and CreA. Moreover, despite previous reports on AsaA being only produced in solid-state culture, deletion of the ortholog of A. oryzae flbC, which is involved in the expression of the solid-state culture-specific genes, did not affect AsaA α-amylase activity, suggesting that FlbC was not associated with asaA expression.


Asunto(s)
Aspergillus oryzae , Factores de Transcripción , Aspergillus , Aspergillus oryzae/genética , Aspergillus oryzae/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Regulación de la Expresión Génica , Glucano 1,4-alfa-Glucosidasa , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
16.
Spectrochim Acta A Mol Biomol Spectrosc ; 246: 119022, 2021 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-33049468

RESUMEN

The knowledge of the composition, morphology, and thickness of surface protective scales, such as SiO2 and Al2O3, is important to control the performance of heat-resistant alloys operated at high temperatures above 1000 °C. Cathodoluminescence (CL) analysis is one of the most promising methods to acquire such information nondestructively. Unlike Al2O3 scale, the use of the brightness of CL image to determine SiO2 scale thickness is difficult because the brightness and color of its acquired CL image depend not only on the thickness of the scale but also on its oxygen potential and impurity concentration. In this study, we investigated the CL spectra of SiO2 scales formed on Fe-20%Si alloy, Si, and MoSi2 to present a method for measuring the thickness of SiO2 scale on silica-forming materials from their CL spectra. A linear calibration curve was obtained from the intensity of the CL peak at 445 nm which originated from the intrinsic defects in SiO2 and the thickness of the SiO2 scale for each heat-treatment temperature (1000 °C, 1200 °C, 1300 °C, and 1400 °C). Data in this study can be adequately employed to derive CL calibration curves at different temperatures because the CL intensity and heat-treatment temperature were fitted according to Arrhenius relationship at different SiO2 scale thickness, regardless of the type of base materials. These results indicated that the thickness of the SiO2 scale formed on silica-forming alloys can be determined by acquiring their CL spectra. Therefore, CL analysis has the potential to be employed as a novel analytical method to control the performance of silica-forming alloys.

17.
PLoS One ; 15(11): e0242054, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33175887

RESUMEN

Tup1-Cyc8 (also known as Tup1-Ssn6) is a general transcriptional corepressor. D-Mannitol (mannitol) and D-sorbitol (sorbitol) are the major polyols in nature. Budding yeast Saccharomyces cerevisiae is unable to assimilate mannitol or sorbitol, but acquires the ability to assimilate mannitol due to a spontaneous mutation in TUP1 or CYC8. In this study, we found that spontaneous mutation of TUP1 or CYC8 also permitted assimilation of sorbitol. Some spontaneous nonsense mutations of CYC8 produced a truncated Cyc8 with a C-terminal polyglutamine. The effects were guanidine hydrochloride-sensitive and were dependent on Hsp104, but were complemented by introduction of CYC8, ruling out involvement of a prion. Assimilation of mannitol and sorbitol conferred by other mutations of TUP1 or CYC8 was guanidine hydrochloride-tolerant. It is physiologically reasonable that S. cerevisiae carries this mechanism to acquire the ability to assimilate major polyols in nature.


Asunto(s)
Codón sin Sentido , Proteínas de Choque Térmico/metabolismo , Péptidos/metabolismo , Proteínas Represoras/genética , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/crecimiento & desarrollo , Regulación Fúngica de la Expresión Génica , Manitol/metabolismo , Proteínas Nucleares/genética , Regiones Promotoras Genéticas , Dominios Proteicos , Proteínas Represoras/química , Proteínas Represoras/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/química , Sorbitol/metabolismo
18.
Front Microbiol ; 11: 552418, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33072013

RESUMEN

Streptococcus dysgalactiae subsp. equisimilis (SDSE) causes cellulitis, bacteremia, and invasive diseases, such as streptococcal toxic shock syndrome. Although SDSE infection is more prevalent among elderly individuals and those with diabetes mellitus than infections with Streptococcus pyogenes (Group A streptococci; GAS) and Streptococcus agalactiae (Group B streptococci; GBS), the mechanisms underlying the pathogenicity of SDSE remain unknown. SDSE possesses a gene hylD encoding a hyaluronate lyase (HylD), whose homologue (HylB) is involved in pathogenicity of GBS, while the role of HylD has not been characterized. In this study, we focused on the enzyme HylD produced by SDSE; HylD cleaves hyaluronate (HA) and generates unsaturated disaccharides via a ß-elimination reaction. Hyaluronate-agar plate assays revealed that SDSE promoted dramatic HA degradation. SDSE expresses both HylD and an unsaturated glucuronyl hydrolase (UGL) that catalyzes the degradation of HA-derived oligosaccharides; as such, SDSE was more effective at HA degradation than other ß-hemolytic streptococci, including GAS and GBS. Although HylD shows some homology to HylB, a similar enzyme produced by GBS, HylD exhibited significantly higher enzymatic activity than HylB at pH 6.0, conditions that are detected in the skin of both elderly individuals and those with diabetes mellitus. We also detected upregulation of transcripts from hylD and ugl genes from SDSE wild-type collected from the mouse peritoneal cavity; upregulated expression of ugl was not observed in ΔhylD SDSE mutants. These results suggested that disaccharides produced by the actions of HylD are capable of triggering downstream pathways that catalyze their destruction. Furthermore, we determined that infection with SDSEΔhylD was significantly less lethal than infection with the parent strain. When mouse skin wounds were infected for 2 days, intensive infiltration of neutrophils was observed around the wound areas infected with SDSE wild-type but not SDSEΔhylD. Our investigation suggested that HylD and UGL play important roles in nutrient acquisition from hosts, followed by the bacterial pathogenicity damaging host tissues.

19.
Sci Rep ; 10(1): 18691, 2020 10 29.
Artículo en Inglés | MEDLINE | ID: mdl-33122638

RESUMEN

Saprophytic bacteria and plants compete for limited nutrient sources. Bacillus subtilis grows well on steamed soybeans Glycine max to produce the fermented food, natto. Here we focus on bacterial responses in conflict between B. subtilis and G. max. B. subtilis cells maintained high growth rates specifically on non-germinating, dead soybean seeds. On the other hand, viable soybean seeds with germinating capability attenuated the initial growth of B. subtilis. Thus, B. subtilis cells may trigger saprophytic growth in response to the physiological status of G. max. Scanning electron microscope observation indicated that B. subtilis cells on steamed soybeans undergo morphological changes to form apertures, demonstrating cell remodeling during saprophytic growth. Further, transcriptomic analysis of B. subtilis revealed upregulation of the gene cluster, yesOPQR, in colonies growing on steamed soybeans. Recombinant YesO protein, a putative, solute-binding protein for the ATP-binding cassette transporter system, exhibited an affinity for pectin-derived oligosaccharide from plant cell wall. The crystal structure of YesO, in complex with the pectin oligosaccharide, was determined at 1.58 Å resolution. This study expands our knowledge of defensive and offensive strategies in interspecies competition, which may be promising targets for crop protection and fermented food production.


Asunto(s)
Bacillus subtilis/fisiología , Pared Celular/metabolismo , Glycine max/metabolismo , Interacciones Huésped-Patógeno , Proteínas de Plantas/metabolismo , Bacillus subtilis/genética , Bacillus subtilis/crecimiento & desarrollo , Genes Bacterianos , Proteínas de Plantas/genética , Unión Proteica , Semillas/microbiología , Glycine max/embriología , Glycine max/microbiología
20.
Chem Commun (Camb) ; 56(82): 12415-12418, 2020 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-32936134

RESUMEN

We introduce thio-substituents at the 7- and 8-positions of a flavin analogue, which allows for the coordination of metal ions, and demonstrate, based on both experimental and theoretical methods, that the formed Cu2+-based supramolecular assembled complex shows very high selective sorting of semiconducting single-walled carbon nanotubes with (8,6)- and (9,4)-chiralities.

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