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1.
PLoS One ; 15(8): e0237616, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32790803

RESUMO

Patients with large iris defects not only suffer from functional disadvantages but also from aesthetic limitations. The aim of this study was to evaluate the aesthetic outcome of iris reconstruction using an artificial iris (AI). In this study, 82 eyes of 79 consecutive patients with mostly traumatic partial or total aniridia that underwent iris reconstruction surgery using a custom-made silicone AI (HumanOptics, Erlangen, Germany). Pre- and postoperative photographs of 66 patients were analysed subjectively and objectively. Subjective evaluation was based questionnaires. Objective evaluation included measurement of pupil centration and iris colour analysis. Averaged hues from iris areas were transferred to numerical values using the LAB-colour-system. Single parameters and overall difference value (ΔE) were compared between AI and remaining iris (RI), as well as AI and fellow eye iris (FI). Patients, eye doctors and laymen rated the overall aesthetic outcome with 8.9 ±1.4, 7.7 ±1.1 and 7.3 ±1.1 out of 10 points, respectively. Mean AI decentration was 0.35 ±0.24 mm. Better pupil centration correlated with a higher overall score for aesthetic outcome (p<0.05). The AI was on average 4.65 ±10 points brighter than RI and FI. Aniridia treatment using a custom-made artificial iris prosthesis offers a good aesthetic outcome. Pupil centration was a key factor that correlated with the amount of aesthetic satisfaction. The AI was on average slightly brighter than the RI and FI.

2.
J Cataract Refract Surg ; 46(8): 1184-1188, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32818330

RESUMO

PURPOSE: To assess whether the combined implantation of a monofocal IOL and an artificial iris had an effect on the IOL's optical performance. SETTING: David J. Apple International Laboratory for Ocular Pathology, Heidelberg, Germany. DESIGN: In vitro laboratory study. METHODS: IOL optical quality was assessed using an OptiSpheric IOL Pro II to measure the IOL's modulation transfer function (MTF) at 3.0 mm pupil size and spatial frequency of 100 lp/mm. Three ASPIRA-aAY IOLs with different base powers, 10.0 diopter (D) (IOL A), 20.0 D (IOL B), and 30.0 D (IOL C) were measured before and after suturing the IOL to an ArtificialIris (AI). The degree of IOL decentration about the center of the AI was also evaluated. RESULTS: The mean MTF values prior to suturing were 0.57, 0.65, and 0.63 for IOLs A, B, and C, respectively. After suturing to the AI, the mean MTF values were 0.52, 0.54, and 0.55 for IOLs A, B, and C, respectively. The decentration values in vertical direction were 0.20 mm, 0.00 mm, and 0.02 mm for IOLs A, B, and C, respectively. In horizontal direction, the decentration values were 0.42 mm, 0.10 mm, and 0.03 mm for IOLs A, B, and C, respectively. CONCLUSIONS: The MTF decreased slightly in all 3 IOLs after they were sutured to the AI. The small differences, however, should be clinically irrelevant. This laboratory assessment showed that suturing of the IOL to the AI can be performed in a reliable and reproducible manner without deteriorating optical quality.

3.
Chembiochem ; 2020 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-32798264

RESUMO

Singlet oxygen is a reactive oxygen species undesired in living cells but a rare and valuable reagent in chemical synthesis. We present a fluorescence spectroscopic analysis of the singlet oxygen formation activity of commercial peroxidases and novel peroxygenases. Singlet oxygen sensor green (SOSG) is used as fluorogenic singlet oxygen trap. Establishing a kinetic model for the reaction cascade to the fluorescent SOSG endoperoxide permits a kinetic analysis of enzymatic singlet oxygen formation. All peroxidases and peroxygenases show singlet oxygen formation, no singlet oxygen activity could be found for any catalase under investigation. Substrate inhibition is found for all reactive enzymes. The commercial dye decolorizing peroxidase industrially used for dairy bleaching shows the highest singlet oxygen activity and the lowest inhibition. This enzyme was immobilized on a textile carrier and successfully applied for a chemical synthesis. Here, ascaridole was synthesized via enzymatically produced singlet oxygen.

4.
Future Microbiol ; 15: 801-831, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32692252

RESUMO

Antimicrobial resistance to virtually all clinically applied antibiotic classes severely limits the available options to treat bacterial infections. Hence, there is an urgent need to develop and evaluate new antibiotics and targets with resistance-breaking properties. Bacterial cell division has emerged as a new antibiotic target pathway to counteract multidrug-resistant pathogens. New approaches in antibiotic discovery and bacterial cell biology helped to identify compounds that either directly interact with the major cell division protein FtsZ, thereby perturbing the function and dynamics of the cell division machinery, or affect the structural integrity of FtsZ by inducing its degradation. The impressive antimicrobial activities and resistance-breaking properties of certain compounds validate the inhibition of bacterial cell division as a promising strategy for antibiotic intervention.

5.
mBio ; 11(3)2020 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-32605984

RESUMO

Antibiotic acyldepsipeptides (ADEPs) deregulate ClpP, the proteolytic core of the bacterial Clp protease, thereby inhibiting its native functions and concomitantly activating it for uncontrolled proteolysis of nonnative substrates. Importantly, although ADEP-activated ClpP is assumed to target multiple polypeptide and protein substrates in the bacterial cell, not all proteins seem equally susceptible. In Bacillus subtilis, the cell division protein FtsZ emerged to be particularly sensitive to degradation by ADEP-activated ClpP at low inhibitory ADEP concentrations. In fact, FtsZ is the only bacterial protein that has been confirmed to be degraded in vitro as well as within bacterial cells so far. However, the molecular reason for this preferred degradation remained elusive. Here, we report the unexpected finding that ADEP-activated ClpP alone, in the absence of any Clp-ATPase, leads to an unfolding and subsequent degradation of the N-terminal domain of FtsZ, which can be prevented by the stabilization of the FtsZ fold via nucleotide binding. At elevated antibiotic concentrations, importantly, the C terminus of FtsZ is notably targeted for degradation in addition to the N terminus. Our results show that different target structures are more or less accessible to ClpP, depending on the ADEP level present. Moreover, our data assign a Clp-ATPase-independent protein unfolding capability to the ClpP core of the bacterial Clp protease and suggest that the protein fold of FtsZ may be more flexible than previously anticipated.IMPORTANCE Acyldepsipeptide (ADEP) antibiotics effectively kill multidrug-resistant Gram-positive pathogens, including vancomycin-resistant enterococcus, penicillin-resistant Streptococcus pneumoniae (PRSP), and methicillin-resistant Staphylococcus aureus (MRSA). The antibacterial activity of ADEP depends on a new mechanism of action, i.e., the deregulation of bacterial protease ClpP that leads to bacterial self-digestion. Our data allow new insights into the mode of ADEP action by providing a molecular explanation for the distinct bacterial phenotypes observed at low versus high ADEP concentrations. In addition, we show that ClpP alone, in the absence of any unfoldase or energy-consuming system, and only activated by the small molecule antibiotic ADEP, leads to the unfolding of the cell division protein FtsZ.

6.
Front Immunol ; 11: 1151, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32695096

RESUMO

Background and Aims: In primary biliary cholangitis (PBC), antibodies to a peptide of the muscarinic acetylcholine receptor 3 (mAChR3) have been described. Since the mAChR3 is expressed on cholangiocytes and mAChR3-signaling is involved in the pathogenesis of chronic inflammatory biliary diseases, we wanted to investigate whether anti-mAChR3-antibodies influence the function of the receptor and the proliferative response of cholangiocytes. Methods: Immunoglobulins were isolated by ammonium sulfate precipitation using sera from patients with PBC (n = 63) and with other chronic liver disorders (n = 150). All immunoglobulins were analyzed by a luminometric assay using Chinese hamster ovary (CHO) cells overexpressing the mAChR3 and cholangiocytes (TFK-1-cells) expressing the receptor constitutively. Cell proliferation was measured by 3H-thymidine assay. PBC patients were also analyzed in the follow-up. Results: Antibodies inhibiting the mAChR3 were found in 49 and 79% of PBC patients using CHO-cells or TFK-1-cells, respectively, but only in up to 26% of controls (p < 0.01). Stimulatory antibodies were hardly detected. Antibody reactivity only marginally changed during the course of the disease, independently of the choice of treatment (ursodeoxycholic acid, immunosuppressive therapy, or no medication). There was no correlation with laboratory, clinical or histological parameters, but the antibodies were more frequently found in PBC patients with a benign course (96%) than in patients with active disease progressing to late stages within 10 years (57%; p < 0.01). Proliferation of cells was not influenced by immunoglobulins from PBC-patients. Conclusion: Sera from patients with PBC contain inhibitory antibodies to the mAChR3 on cholangiocytes (TFK-1 cells) without influencing TFK-1-cell proliferation. These antibodies were predominantly observed in patients with non-progressing PBC.

7.
Artigo em Inglês | MEDLINE | ID: mdl-32569026

RESUMO

PURPOSE: To assess whether the combined implantation of a monofocal intraocular lens (IOL) and an artificial iris has an effect on the IOL's optical performance. SETTING: David J. Apple International Laboratory for Ocular Pathology, Heidelberg, Germany. DESIGN: In vitro laboratory study. METHODS: IOL optical quality was assessed using an OptiSpheric IOL Pro II to measure the IOL's modulation transfer function (MTF) at 3.0 mm pupil size and spatial frequency of 100 lp/mm. Three ASPIRA-aAY IOLs with different base powers, 10.0 diopter (D) (IOL A), 20.0 D (IOL B), and 30.0 D (IOL C) were measured before and after suturing the IOL to an ArtificialIris (AI). The degree of lens decentration in respect to the center of the AI was also evaluated. RESULTS: The mean MTF values prior to suturing were 0.57, 0.65, and 0.63 for IOLs A, B, and C, respectively. After suturing to the AI, the mean MTF values were 0.52, 0.54, and 0.55 for IOLs A, B, and C, respectively. The decentration values in vertical direction were 0.20 mm, 0.00 mm, and 0.02 mm for IOLs A, B, and C. In horizontal direction, the decentration values were 0.42 mm, 0.10 mm, and 0.03 mm for IOLs A, B, and C. CONCLUSIONS: The MTF decreased slightly in all 3 IOLs after they were sutured to the AI. The small differences, however, should be clinically irrelevant. This laboratory assessment showed that suturing of the IOL to the AI can be done in a reliable and reproducible manner without deteriorating optical quality.

8.
Cell Host Microbe ; 28(2): 335-349.e6, 2020 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-32504577

RESUMO

Although there is no effective cure for chronic hepatitis B virus (HBV) infection, antibodies are protective and correlate with recovery from infection. To examine the human antibody response to HBV, we screened 124 vaccinated and 20 infected, spontaneously recovered individuals. The selected individuals produced shared clones of broadly neutralizing antibodies (bNAbs) that targeted 3 non-overlapping epitopes on the HBV S antigen (HBsAg). Single bNAbs protected humanized mice against infection but selected for resistance mutations in mice with prior established infection. In contrast, infection was controlled by a combination of bNAbs targeting non-overlapping epitopes with complementary sensitivity to mutations that commonly emerge during human infection. The co-crystal structure of one of the bNAbs with an HBsAg peptide epitope revealed a stabilized hairpin loop. This structure, which contains residues frequently mutated in clinical immune escape variants, provides a molecular explanation for why immunotherapy for HBV infection may require combinations of complementary bNAbs.

10.
Ophthalmologe ; 2020 Apr 15.
Artigo em Alemão | MEDLINE | ID: mdl-32296922

RESUMO

The functional results and the occurrence of side effects (especially photic phenomena) for multifocal intraocular lenses (IOL) are difficult to predict. Furthermore, in the course of life patients can develop diseases in which a multifocal optic would be a disadvantage. In these cases exchange of the IOL is the only treatment option. Implantation of a monofocal or monofocal toric IOL in the capsular bag and a supplementary trifocal IOL in the ciliary sulcus in a single operation, known as a duet procedure, provides trifocality that can be easily reversed if necessary.

11.
Development ; 147(9)2020 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-32238425

RESUMO

Direction-selective T4/T5 neurons exist in four subtypes, each tuned to visual motion along one of the four cardinal directions. Along with their directional tuning, neurons of each T4/T5 subtype orient their dendrites and project their axons in a subtype-specific manner. Directional tuning, thus, appears strictly linked to morphology in T4/T5 neurons. How the four T4/T5 subtypes acquire their distinct morphologies during development remains largely unknown. Here, we investigated when and how the dendrites of the four T4/T5 subtypes acquire their specific orientations, and profiled the transcriptomes of all T4/T5 neurons during this process. This revealed a simple and stable combinatorial code of transcription factors defining the four T4/T5 subtypes during their development. Changing the combination of transcription factors of specific T4/T5 subtypes resulted in predictable and complete conversions of subtype-specific properties, i.e. dendrite orientation and matching axon projection pattern. Therefore, a combinatorial code of transcription factors coordinates the development of dendrite and axon morphologies to generate anatomical specializations that differentiate subtypes of T4/T5 motion-sensing neurons.

12.
Med Sci Sports Exerc ; 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32251255

RESUMO

For three decades, studies have demonstrated the therapeutic efficacy of perfluorocarbons (PFCs) in reducing the onset of decompression trauma. However, none of these emulsion-based preparations are accepted for therapeutic use in the western world, mainly because of severe side-effects and a long organ retention time. A new development to guarantee a stable dispersion without these disadvantages is the encapsulation of PFCs in nanocapsules with an albumin shell. PURPOSE: Newly designed albumin-derived perfluorocarbon-based artificial oxygen carriers (A-AOCs) are used in a rodent in-vivo model as a preventive therapy for decompression sickness (DCS). METHODS: Thirty-seven rats were treated with either A-AOCs (n=12), albumin nanocapsules filled with neutral oil (A-O-N, n=12) or 5% human serum albumin solution (A-0-0, n=13) before a simulated dive. Eleven rats, injected with A-AOCs, stayed at normal pressure (A-AOCs-surface). Clinical, laboratory and histological evaluations were performed. RESULTS: The occurrence of DCS depended on the treatment group. A-AOCs significantly reduced DCS-appearance and mortality. Furthermore, a significant improvement of survival time was found (A-AOCs compared with A-0-0). Histological assessment of A-AOCs-dive compared with A-0-0-dive animals revealed significantly higher accumulation of macrophages, but less blood congestion in the spleen and significantly less hepatic circulatory disturbance, vacuolisation and cell damage. Compared to non-diving controls lactate and myoglobin showed a significant increase in the A-0-0- but not in the A-AOCs-dive group. CONCLUSION: Intravenous application of A-AOCs was well tolerated and effective in reducing the occurrence of DCS, animals showed significantly higher survival rates and less symptoms compared to the albumin group (A-0-0). Analysis of histological results and fast reacting plasma parameters confirmed the preventive properties of A-AOCs.

13.
Chembiochem ; 21(14): 1997-2012, 2020 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-32181548

RESUMO

Acyldepsipeptide (ADEP) is an exploratory antibiotic with a novel mechanism of action. ClpP, the proteolytic core of the caseinolytic protease, is deregulated towards unrestrained proteolysis. Here, we report on the mechanism of ADEP resistance in Firmicutes. This bacterial phylum contains important pathogens that are relevant for potential ADEP therapy. For Staphylococcus aureus, Bacillus subtilis, enterococci and streptococci, spontaneous ADEP-resistant mutants were selected in vitro at a rate of 10-6 . All isolates carried mutations in clpP. All mutated S. aureus ClpP proteins characterised in this study were functionally impaired; this increased our understanding of the mode of operation of ClpP. For molecular insights, crystal structures of S. aureus ClpP bound to ADEP4 were determined. Well-resolved N-terminal domains in the apo structure allow the pore-gating mechanism to be followed. The compilation of mutations presented here indicates residues relevant for ClpP function and suggests that ADEP resistance will occur at a lower rate during the infection process.

14.
Int J Med Microbiol ; 309(6): 151335, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31378704

RESUMO

The type VI secretion system (T6SS) injects effector proteins into neighboring bacteria and host cells. Effector translocation is driven by contraction of a tubular sheath in the cytoplasm that expels an inner needle across the cell envelope. The AAA + ATPase ClpV disassembles and recycles the contracted sheath. While ClpV-1-GFP of the Burkholderia T6SS-1, which targets prokaryotic cells, assembles into randomly localized foci, ClpV-5-GFP of the virulence-associated T6SS-5 displays a polar distribution. The mechanisms underlying the localization of T6SSs to a particular site in the bacterial cell are currently unknown. We recently showed that ClpV-5-GFP retains its polar localization in the absence of all T6SS-5 components during infection of host cells. Herein, we set out to identify factors involved in the distribution of ClpV-5 and ClpV-1 in Burkholderia thailandensis. We show that focal assembly and polar localization of ClpV-5-GFP is not dependent on the intracellular host cell environment, known to contain the signal to induce T6SS-5 gene expression. In contrast to ClpV-5-GFP, localization of ClpV-1-GFP was dependent on the cognate T6SS. Foci formation of both ClpV5-GFP and ClpV-1-GFP was decreased by D cycloserine-mediated inhibition of peptidoglycan synthesis while treatment of B. thailandensis with A22 blocking the cytoskeletal protein MreB did not affect assembly of ClpV-5 and ClpV-1 into single discrete foci. Furthermore, we found that surface contact promotes but is not essential for localization of ClpV-5-GFP to the pole whereas expression of clpV-1-gfp appears to be induced by surface contact. In summary, the study provides novel insights into the localization of ClpV ATPases of T6SSs targeting prokaryotic and eukaryotic cells.


Assuntos
Adenosina Trifosfatases/metabolismo , Proteínas de Bactérias/metabolismo , Burkholderia/fisiologia , Sistemas de Secreção Tipo VI/metabolismo , Fatores de Virulência/metabolismo , Aderência Bacteriana , Burkholderia/efeitos dos fármacos , Burkholderia/genética , Ciclosserina/farmacologia , Células Epiteliais/metabolismo , Células Epiteliais/microbiologia , Células HeLa , Humanos , Peptidoglicano/biossíntese , Peptidoglicano/efeitos dos fármacos , Transporte Proteico/fisiologia , Deleção de Sequência , Sistemas de Secreção Tipo VI/genética
17.
Int J Med Microbiol ; 309(7): 151329, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31331697

RESUMO

Antibiotic acyldepsipeptides (ADEPs) exert potent antibacterial activity in rodent models of bacterial infection and exceptional efficacy against persister cells of methicillin-resistant Staphylococcus aureus (MRSA). The mechanism of ADEP action is unusual in that the antibiotic releases the destructive capacity of over-activated ClpP, the proteolytic core of the bacterial Clp protease. The essential bacterial cell division protein FtsZ had emerged in a previous study as a preferred protein substrate of ADEP-activated ClpP but it is definitely not the only cellular substrate. In the current study, we set out to follow the morphological changes that lead to ADEP-mediated bacterial death in S. aureus and Bacillus subtilis, differentiating between antibacterial effects at low and high ADEP concentrations. Here, fluorescence and time-lapse microscopy data show that cells adopt a characteristic phenotype of cell division inhibition at ADEP levels close to the MIC, but retain the capacity to form viable daughter cells for a substantial period of time when transferred to ADEP-free growth medium. After extended exposure to low ADEP concentrations, nucleoids of B. subtilis started to disorganize and upon compound removal many cells failed to re-organize nucleoids, re-initiate cytokinesis and consequently died. Survival versus cell death of filamentous cells attempting recovery depended on the timing of completion of new septa in relation to the loss of cell envelope integrity. We show that the potential to recover after ADEP removal depends on the antibiotic concentration as well as the treatment duration. When exposed to ADEP at concentrations well above the MIC, biomass production ceased rapidly as did the potential to recover. In time-kill studies both long-time exposure to low ADEP levels as well as short-time exposure to high concentrations proved highly effective, while intermittent concentrations and time frames were not. We here provide new insights into the antimicrobial activity of ADEP antibiotics and the consequences of dosing and timing for bacterial physiology which should be considered in view of a potential therapeutic application of ADEPs.


Assuntos
Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Depsipeptídeos/farmacologia , Antibacterianos/administração & dosagem , Bactérias/citologia , Bactérias/crescimento & desenvolvimento , Bactérias/metabolismo , Proteínas de Bactérias/metabolismo , Divisão Celular/efeitos dos fármacos , Proteínas do Citoesqueleto/metabolismo , Depsipeptídeos/administração & dosagem , Relação Dose-Resposta a Droga , Testes de Sensibilidade Microbiana , Viabilidade Microbiana/efeitos dos fármacos , Fatores de Tempo
18.
Inflammation ; 42(5): 1767-1776, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31175488

RESUMO

In human sepsis, hemolysis is an independent predictor of mortality, but the mechanisms evoking hemolysis have not been fully elucidated. Therefore, we tested the hypotheses that (1) lipopolysaccharide (LPS)-induced hemolysis is dependent on thrombin generation or platelet aggregation and (2) red cell membranes are weakened by LPS. Anesthetized male Wistar rats were subjected to LPS or vehicle for 240 min. The effects of hemostasis inhibition on LPS-induced hemolysis were investigated by use of the thrombin inhibitor argatroban or the platelet function inhibitor eptifibatide. Free hemoglobin concentration, red cell membrane stiffness and red cell morphological changes were determined by spectrophotometry, atomic force microscopy, and light microscopy. Efficacy of argatroban and eptifibatide was assessed by rotational thrombelastometry and impedance aggregometry, respectively. LPS markedly increased free hemoglobin concentration (20.8 µmol/l ± 3.6 vs. 3.5 ± 0.3, n = 6, p < 0.0001) and schistocytes, reduced red cell membrane stiffness, and induced disseminated intravascular coagulation. Inhibition of thrombin formation with argatroban abolished the increase in free hemoglobin concentration, schistocyte formation, and disseminated intravascular coagulation in LPS-treated animals. Eptifibatide had no inhibitory effect. The LPS evoked decrease of red cell stiffness that was not affected by argatroban or eptifibatide. LPS causes hemolysis, schistocyte formation, and red cell membrane weakening in rats. The thrombin inhibitor argatroban but not the platelet inhibitor eptifibatide abolished hemolysis and schistocyte formation. Thus, LPS-induced hemolysis depends on disseminated intravascular coagulation, possibly enhanced by red cell membrane weakening. Clinical studies are necessary to investigate whether thrombin antagonists can decrease hemolysis and mortality in sepsis.


Assuntos
Hemólise/efeitos dos fármacos , Agregação Plaquetária/efeitos dos fármacos , Trombina/antagonistas & inibidores , Animais , Coagulação Intravascular Disseminada/fisiopatologia , Eptifibatida/farmacologia , Membrana Eritrocítica/efeitos dos fármacos , Eritrócitos/efeitos dos fármacos , Humanos , Lipopolissacarídeos/efeitos adversos , Masculino , Ácidos Pipecólicos/farmacologia , Inibidores da Agregação de Plaquetas/farmacologia , Ratos , Ratos Wistar , Trombina/biossíntese
19.
BMC Res Notes ; 12(1): 109, 2019 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-30819219

RESUMO

OBJECTIVE: ClpV, the ATPase of the type VI secretion system (T6SS) recycles cytoplasmic T6SS proteins following effector translocation. Fluorescent protein fusions to ClpV showed that it localizes to discrete and dynamic foci. ClpV-1-sfGFP of the bacterial cell targeting T6SS-1 of Burkholderia thailandensis exhibits a virtually random localization, whereas ClpV-5-sfGFP of the T6SS-5 targeting host cells is located at one or both poles. The mechanisms underlying the differential localization pattern are not known. Previous analysis of T6SSs, which target bacterial cells revealed that ClpV foci formation is dependent on components of the T6SS. Here, we investigated if the T6SS-5 apparatus confers polar localization of ClpV-5. RESULTS: ClpV-5-sfGFP foci formation and localization was examined in a B. thailandensis mutant harboring a deletion of the entire T6SS-5 gene cluster. We found that ClpV-5-sfGFP localization to discrete foci was not abolished in the absence of the T6SS-5 apparatus. Furthermore, the number of ClpV-5-sfGFP foci displaying a polar localization was not significantly different from that of ClpV-5-sfGFP expressed in the wild type genetic background. These findings suggest the presence of a T6SS-independent localization mechanism for ClpV-5 of the T6SS-5 targeting host cells.


Assuntos
Adenosina Trifosfatases , Proteínas de Bactérias , Burkholderia , Sistemas de Secreção Tipo VI
20.
Chem Commun (Camb) ; 55(22): 3298-3301, 2019 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-30810550

RESUMO

Two supramolecular nanocapsules were generated by multi-component self-assembly of the novel bisphosphoric acid (R,R)-6 with suitable bis- and trisamidines. The resulting chiral, hydrogen-bonded capsules are stable even in polar media and at low concentrations and can be employed for the binding of C70-fullerene in solution.

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