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1.
Int Microbiol ; 22(4): 461-470, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31098825

RESUMO

To date, tripartite tricarboxylate transport (TTT) systems are not well characterized in most organisms. To investigate which carbon sources are transported by the TTT system of A. mimigardefordensis DPN7T, single deletion mutants were generated lacking either completely both sets of genes encoding for these transport systems tctABCDE1 and tctABDE2 in the organism or the two genes encoding for the regulatory components of the third chosen TTT system, tctDE3. Deletion of tctABCDE1 (MIM_c39170-MIM_c39210) in Advenella mimigardefordensis strain DPN7T led to inhibition of growth of the cells with citrate indicating that TctABCDE1 is the transport system for the uptake of citrate. Because of the negative phenotype, it was concluded that this deletion cannot be substituted by other transporters encoded in the genome of strain DPN7T. A triple deletion mutant of A. mimigardefordensis lacking both complete TTT transport systems and the regulatory components of the third chosen system (ΔTctABCDE1 ΔTctABDE2 ΔTctDE3) showed a leaky growth with α-ketoglutarate in comparison with the wild type. The other investigated TTT (TctABDE3, MIM_c17190-MIM_c17220) is most probably involved in the transport of α-ketoglutarate. Additionally, thermoshift assays with TctC1 (MIM_c39190) showed a significant shift in the melting temperature of the protein in the presence of citrate whereas no shift occurred with α-ketoglutarate. A dissociation constant Kd for citrate of 41.7 µM was determined. Furthermore, alternative α-ketoglutarate transport was investigated via in silico analysis.


Assuntos
Alcaligenaceae/metabolismo , Proteínas de Bactérias/metabolismo , Proteínas de Transporte/metabolismo , Citratos/metabolismo , Alcaligenaceae/genética , Alcaligenaceae/crescimento & desenvolvimento , Proteínas de Bactérias/genética , Transporte Biológico , Proteínas de Transporte/genética , Deleção de Genes , Óperon
2.
Andrology ; 12(4): 821-829, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-37753879

RESUMO

BACKGROUND: Little is known about patients' pre-treatment expectations in Peyronie's disease (PD). OBJECTIVE: To evaluate in detail patients' expectations of conservative therapy and surgery. PATIENTS AND METHODS: This multi-center study prospectively enrolled 317 PD patients, who were scheduled to receive conservative therapy or surgery between 2019 and 2022 at the Department of Urology of the University Medical Center Hamburg-Eppendorf, and the Center of Reproductive Medicine and Andrology, University Medical Center Muenster, both Germany. The primary end-point was patients' pre-treatment expectations of conservative therapy and surgery, measured with the Stanford Expectations of Treatment Scale (SETS). Secondary end-points included patient-reported psychological and physical symptoms, penile pain, symptom bother and erectile function, measured with the Peyronie's disease questionnaire (PDQ) and International Index of Erectile Function Erectile Function Domain (IIEF-EF). RESULTS: In total, 239 (75%) and 78 (25%) patients were scheduled for the conservative therapy and surgery, respectively. Patients undergoing surgery had higher positive and negative mean SETS expectations scores (14 vs. 11, p < 0.001; 9.6 vs. 6.0, p < 0.001). In multivariable analysis, surgery was an independent predictor of positive and negative patients' pre-treatment expectations (all p ≤ 0.001). In thematic analysis, patients undergoing surgery emphasized distinct themes of pre-treatment expectations. Patients undergoing surgery had higher mean PDQ symptom bother as well as higher psychological and physical symptom scores (14 vs. 10, p < 0.001; 9.2 vs. 7.1, p = 0.001). There were significant positive correlations between SETS negative expectation score and PDQ symptom bother (|ρ| = 0.25; p < 0.001) as well as PDQ psychological and physical symptoms score, respectively (|ρ| = 0.21; p = 0.001). CONCLUSION: PD patients expect both more benefit and more harm from surgery. In addition, patients undergoing surgery have more psychological and physical symptoms and more symptom bother. To set realistic expectations, it is of pivotal importance to assess patients' expectations before starting treatment.


Assuntos
Disfunção Erétil , Induração Peniana , Masculino , Humanos , Induração Peniana/cirurgia , Induração Peniana/diagnóstico , Estudos Prospectivos , Resultado do Tratamento , Ereção Peniana , Pênis
3.
Enzyme Microb Technol ; 160: 110095, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35810625

RESUMO

Since the role of biobased plastics increases every year, the search for alternatives to petrol-based polymers is very important. Variovorax paradoxus TBEA6 is able to grow with 3,3'-thiodipropionic acid (TDP) as sole source for carbon and energy. TDP can be used as a precursor substrate for the synthesis of polythioesters (PTE). To increase the feasibility of PTE synthesis, a good understanding of the degradation pathway of TDP in V. paradoxus TBEA6 is essential. Therefore, two putative 3-hydroxyisobutyryl-CoA hydrolases (VPARA_03110 & VPARA_05510) and two putative 3-hydroxypropionate dehydrogenases (VPARA_41140 & VPARA_54550) were investigated in this study. The deletion mutant V. paradoxus ∆VPARA_05510 showed a TDP-negative phenotype during growth experiments. The ability to grow with TDP as sole carbon source was successfully restored by complementation. Supernatant analysis revealed that the deletion mutant did not metabolize TDP or 3MP anymore. A specific enzyme activity up to 0.032 U/mg for the purified 3-hydroxyisobutyryl-CoA hydrolase VPARA_05510 was determined. A shift in the proteins (VPARA_54550) melting temperature of 6 °C with 2000 µM 3HP in comparison to protein without ligand was observed during thermal shift assays with the putative 3-hydroxypropionate dehydrogenase.


Assuntos
Comamonadaceae , Alcaligenes , Carbono/metabolismo , Comamonadaceae/genética , Proteínas de Ligação a DNA/metabolismo , Propionatos
4.
FEBS J ; 288(16): 4905-4917, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33630388

RESUMO

Recently, CxaP, a sugar acid substrate binding protein (SBP) from Advenella mimigardefordensis strain DPN7T , was identified as part of a novel sugar uptake strategy. In the present study, the protein was successfully crystallized. Although several SBP structures of tripartite ATP-independent periplasmic transporters have already been solved, this is the first structure of an SBP accepting multiple sugar acid ligands. Protein crystals were obtained with bound d-xylonic acid, d-fuconic acid d-galactonic and d-gluconic acid, respectively. The protein shows the typical structure of an SBP of a tripartite ATP-independent periplasmic transporter consisting of two domains linked by a hinge and spanned by a long α-helix. By analysis of the structure, the substrate binding site of the protein was identified. The carboxylic group of the sugar acids interacts with Arg175, whereas the coordination of the hydroxylic groups at positions C2 and C3 is most probably realized by Arg154 and Asn151. Furthermore, it was observed that 2-keto-3-deoxy-d-gluconic acid is bound in protein crystals that were crystallized without the addition of any ligand, indicating that this molecule is prebound to the protein and is displaced by the other ligands if they are available. DATABASE: Structural data of CxaP complexes are available in the worldwide Protein Data Bank (https://www.rcsb.org) under the accession codes 7BBR (2-keto-3-deoxy-d-gluconic acid), 7BCR (d-galactonic acid), 7BCN (d-xylonic acid), 7BCO (d-fuconic acid) and 7BCP (d-gluconic acid).


Assuntos
Alcaligenaceae/química , Proteínas de Bactérias/química , Proteínas de Membrana Transportadoras/química , Açúcares Ácidos/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Cristalografia por Raios X , Proteínas de Membrana Transportadoras/metabolismo , Modelos Moleculares , Açúcares Ácidos/metabolismo
5.
Front Pain Res (Lausanne) ; 2: 735838, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35295496

RESUMO

In recent years, preclinical pain research has failed to develop genuinely new analgesics for clinical use. This fact is reflected by a high number of patients, limited drug efficacy accompanied by side effects, and a long-term opioid intake. Two main aspects have been addressed, which hinder translation: the use of non-relevant pain models and a mismatch between pain-related outcomes in preclinical and clinical studies. Conversely, disease-specific pain models that mirror more closely the clinical situation and multidimensional behavioral outcome measures that objectively and reproducibly assess relevant pain-related symptoms in a preclinical setting could improve translation. Mechanistically, a matter of debate is the role of Ly6G+ neutrophil granulocytes (NGs) for pain. NGs are essential to eliminate pathogens and promote the wound healing process. For this purpose, there is a need to release various pro- and anti-inflammatory mediators, some of which could ameliorate or enhance pain. However, the contribution of NGs to different pain entities is contradictory for reflex-based tests, and completely unknown in the context of non-evoked pain (NEP) and movement-evoked pain (MEP). First, we combined withdrawal reflex-based assays with novel video-based assessments for NEP- and MEP-related behavior in two mouse pain models. The pain models utilized in this study were incision (INC) and pathogen/adjuvant-induced inflammation (CFA), translating well to postsurgical and inflammatory pain entities. Second, we depleted NGs and applied a set of behavioral assessments to investigate the role of NG migration in different pain modalities. Our comprehensive behavioral approach identified pain-related behaviors in mice that resemble (NEP) or differentiate (MEP) behavioral trajectories in comparison to mechanical and heat hypersensitivity, thereby indicating modality-dependent mechanisms. Further, we show that injury-induced accumulation of NGs minimally affects pain-related behaviors in both pain models. In conclusion, we report a novel assessment to detect NEP in mice after unilateral injuries using a more unbiased approach. Additionally, we are capable of detecting an antalgic gait for both pain entities with unique trajectories. The different trajectories between MEP and other pain modalities suggest that the underlying mechanisms differ. We further conclude that NGs play a subordinate role in pain-related behaviors in incisional and inflammatory pain.

6.
Adv Mater ; 33(5): e2006853, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33354774

RESUMO

Pinning-type magnets with high coercivity at high temperatures are at the core of thriving clean-energy technologies. Among these, Sm2 Co17 -based magnets are excellent candidates owing to their high-temperature stability. However, despite intensive efforts to optimize the intragranular microstructure, the coercivity currently only reaches 20-30% of the theoretical limits. Here, the roles of the grain-interior nanostructure and the grain boundaries in controlling coercivity are disentangled by an emerging magnetoelectric approach. Through hydrogen charging/discharging by applying voltages of only ≈1 V, the coercivity is reversibly tuned by an unprecedented value of ≈1.3 T. In situ magneto-structural characterization and atomic-scale tracking of hydrogen atoms reveal that the segregation of hydrogen atoms at the grain boundaries, rather than the change of the crystal structure, dominates the reversible and substantial change of coercivity. Hydrogen reduces the local magnetocrystalline anisotropy and facilitates the magnetization reversal starting from the grain boundaries. This study opens a way to achieve the giant magnetoelectric effect in permanent magnets by engineering grain boundaries with hydrogen atoms. Furthermore, it reveals the so far neglected critical role of grain boundaries in the conventional magnetization-switching paradigm of pinning-type magnets, suggesting a critical reconsideration of engineering strategies to overcome the coercivity limits.

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