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Xue Y, Zheng M, Cheng Z, Li S, Yang S, Liu Y, Qian Y, Huang X. Dynamic Simulation of Nitrifying Microbial Communities for Establishing Acidic Partial Nitritation in Suspended Activated Sludge. Environ Sci Technol 2023; 57:17542-17552. [PMID: 37909179 DOI: 10.1021/acs.est.3c01282] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/02/2023]
Abstract
Acidic partial nitritation (PN) is a promising technology to achieve low-cost and energy-efficient shortcut nitrogen removal from wastewater. However, a comprehensive understanding of the acidic PN under dynamic changes of pH in a sequencing batch reactor (SBR) is still lacking. In this study, we successfully established acidic PN (NO2- accumulation ratio >80%) under dynamic pH variation from 7.0 to 4.5 in a lab-scale SBR. By accumulating in situ free nitrous acid (FNA) generation based on the dynamic pH change, acidic PN maintained stability even at a low NH4+ concentration of 100 mg N L-1. The microbial community analysis revealed that two ammonium-oxidizing bacteria (AOB) genera, Nitrosospira and Nitrosomonas, successfully coexisted and cooperated during acidic PN. None of the species of nitrite-oxidizing bacteria (NOB) showed adaptation to intermittent inhibition of in situ FNA even under high DO conditions (>4.0 mg O2 L-1). Furthermore, we innovatively incorporated the classic nitrification model with the growth and decay of different nitrifying bacterial species and their inhibition by pH, FNA, and free ammonia (FA) to predict the nitrifying microbial communities shifting for establishing acidic PN. The extended model was calibrated by using short-term batch experiments and was validated by using long-term dynamic data of the nitrifying microbial community during SBR operation. The validated model was further used to identify feasible influent conditions for the SBR PN process, including influent HCO3- concentration, NH4+ concentration and molar ratio (HCO3/NH4+). Outcomes from this study support the optimal design of acidic PN-based short-cut nitrogen removal processes for future application.
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Affiliation(s)
- Yu Xue
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China
| | - Min Zheng
- Australian Centre for Water and Environmental Biotechnology, The University of Queensland, St. Lucia, QLD 4072, Australia
| | - Zhao Cheng
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China
| | - Siqi Li
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China
| | - Shaolin Yang
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China
| | - Yanchen Liu
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China
| | - Yi Qian
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China
| | - Xia Huang
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China
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Korel A, Samokhin A, Zemlyakova E, Pestov A, Blinova E, Zelikman M, Tkachenko V, Bets V, Kretien S, Arzhanova E, Litvinova E. A Carboxyethylchitosan Gel Cross-Linked with Glutaraldehyde as a Candidate Carrier for Biomedical Applications. Gels 2023; 9:756. [PMID: 37754437 PMCID: PMC10531016 DOI: 10.3390/gels9090756] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Revised: 07/28/2023] [Accepted: 08/03/2023] [Indexed: 09/28/2023] Open
Abstract
To date, few publications describe CEC's properties and possible applications-thus, further evaluation of these properties is a point of interest. The present in vitro model study aimed to evaluate a carboxyethylchitosan (CEC) gel with a degree of substitution of 1, cross-linked with glutaraldehyde at a polymer:aldehyde molar ratio of 10:1, as a potential carrier for delivering bacteriophages to various pH-fixed media (acidic, alkaline), and including gastrointestinal tract (GIT) variable medium. A quantitative analysis of bacteriophages released from the gel was performed using photon correlation spectrophotometry, and phage activity after emission into medium was evaluated using the spot test. The results showed that the CEC gel's maximum swelling ratios were at a nearly neutral alkaline pH. Increasing temperature enhances the swelling ratio of the gel independent from pH, up to 1127% at 37 °C and alkaline pH. The UV and photon correlation spectrophotometry showed equal gel release kinetics in both fixed media with acidic (pH = 2.2) and alkaline (pH = 7.4) pH environments at 37 °C, with the maximum release within two hours. However, phage lytic activity in the spot test during this simulation was absent. At the same time, we obtained an opaque phage lytic activity in the alkaline pH-fixed medium for at least three hours. Phages released from the tested CEC gel in different pHs suggest that this gel could be used for applications that require fast release at the treatment site both in acidic and alkaline pH. Such treatment sites could be a wound or even soil with mild acidic or alkaline pH. However, such CEC gel is not suitable as a delivery system to the GIT because of possible transported acid-sensitive agent (such as phages) release and destruction already in the stomach.
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Affiliation(s)
- Anastasia Korel
- Faculty of Physical Engineering, Novosibirsk State Technical University, 630073 Novosibirsk, Russia; (A.K.); (E.B.); (V.B.); (S.K.); (E.A.); (E.L.)
| | - Alexander Samokhin
- Faculty of Physical Engineering, Novosibirsk State Technical University, 630073 Novosibirsk, Russia; (A.K.); (E.B.); (V.B.); (S.K.); (E.A.); (E.L.)
| | - Ekaterina Zemlyakova
- Institute of Organic Synthesis n.a. I. Ya. Postovsky UB RAS, 620137 Ekaterinburg, Russia; (E.Z.); (A.P.)
| | - Alexander Pestov
- Institute of Organic Synthesis n.a. I. Ya. Postovsky UB RAS, 620137 Ekaterinburg, Russia; (E.Z.); (A.P.)
| | - Elena Blinova
- Faculty of Physical Engineering, Novosibirsk State Technical University, 630073 Novosibirsk, Russia; (A.K.); (E.B.); (V.B.); (S.K.); (E.A.); (E.L.)
| | - Maxim Zelikman
- Institute of Solid State Chemistry and Mechanochemistry SB RAS, 630090 Novosibirsk, Russia;
| | - Vadim Tkachenko
- Institute of Nuclear Physics SB RAS, 630090 Novosibirsk, Russia;
| | - Viktoria Bets
- Faculty of Physical Engineering, Novosibirsk State Technical University, 630073 Novosibirsk, Russia; (A.K.); (E.B.); (V.B.); (S.K.); (E.A.); (E.L.)
| | - Svetlana Kretien
- Faculty of Physical Engineering, Novosibirsk State Technical University, 630073 Novosibirsk, Russia; (A.K.); (E.B.); (V.B.); (S.K.); (E.A.); (E.L.)
- Novosibirsk Research Institute of Traumatology and Orthopedics, 630091 Novosibirsk, Russia
| | - Elena Arzhanova
- Faculty of Physical Engineering, Novosibirsk State Technical University, 630073 Novosibirsk, Russia; (A.K.); (E.B.); (V.B.); (S.K.); (E.A.); (E.L.)
| | - Ekaterina Litvinova
- Faculty of Physical Engineering, Novosibirsk State Technical University, 630073 Novosibirsk, Russia; (A.K.); (E.B.); (V.B.); (S.K.); (E.A.); (E.L.)
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Li L, Zhou J, Wang X, Gracia J, Valvidares M, Ke J, Fang M, Shen C, Chen JM, Chang YC, Pao CW, Hsu SY, Lee JF, Ruotolo A, Chin Y, Hu Z, Huang X, Shao Q. Spin-Polarization Strategy for Enhanced Acidic Oxygen Evolution Activity. Adv Mater 2023; 35:e2302966. [PMID: 37436805 DOI: 10.1002/adma.202302966] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Revised: 06/30/2023] [Accepted: 07/11/2023] [Indexed: 07/13/2023]
Abstract
Spin-polarization is known as a promising way to promote the anodic oxygen evolution reaction (OER), since the intermediates and products endow spin-dependent behaviors, yet it is rarely reported for ferromagnetic catalysts toward acidic OER practically used in industry. Herein, the first spin-polarization-mediated strategy is reported to create a net ferromagnetic moment in antiferromagnetic RuO2 via dilute manganese (Mn2+ ) (S = 5/2) doping for enhancing OER activity in acidic electrolyte. Element-selective X-ray magnetic circular dichroism reveals the ferromagnetic coupling between Mn and Ru ions, fulfilling the Goodenough-Kanamori rule. The ferromagnetism behavior at room temperature can be well interpreted by first principles calculations as the interaction between the Mn2+ impurity and Ru ions. Indeed, Mn-RuO2 nanoflakes exhibit a strongly magnetic field enhanced OER activity, with the lowest overpotential of 143 mV at 10 mA cmgeo -2 and negligible activity decay in 480 h stability (vs 200 mV/195 h without magnetic field) as known for magnetic effects in the literature. The intrinsic turnover frequency is also improved to reach 5.5 s-1 at 1.45 VRHE . This work highlights an important avenue of spin-engineering strategy for designing efficient acidic oxygen evolution catalysts.
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Affiliation(s)
- Ling Li
- College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Jiangsu, 215123, China
| | - Jing Zhou
- Key Laboratory of Interfacial Physics and Technology, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai, 201800, China
| | - Xiao Wang
- Max Planck Institute for Chemical Physics of Solids, Nothnitzer Strasse 40, 01187, Dresden, Germany
| | | | - Manuel Valvidares
- ALBA Synchrotron Light Source, E-08290 Cerdanyola del Vall`es, Barcelona, 08290, Spain
| | - Jia Ke
- College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Jiangsu, 215123, China
| | - Miaomiao Fang
- College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Jiangsu, 215123, China
| | - Chenqi Shen
- College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Jiangsu, 215123, China
| | - Jin-Ming Chen
- National Synchrotron Radiation Research Center, 101 Hsin-Ann Road, Hsinchu, 30076, Taiwan
| | - Yu-Chung Chang
- National Synchrotron Radiation Research Center, 101 Hsin-Ann Road, Hsinchu, 30076, Taiwan
| | - Chih-Wen Pao
- National Synchrotron Radiation Research Center, 101 Hsin-Ann Road, Hsinchu, 30076, Taiwan
| | - Su-Yang Hsu
- National Synchrotron Radiation Research Center, 101 Hsin-Ann Road, Hsinchu, 30076, Taiwan
| | - Jyh-Fu Lee
- National Synchrotron Radiation Research Center, 101 Hsin-Ann Road, Hsinchu, 30076, Taiwan
| | - Antonio Ruotolo
- Department of Physics and Astronomy, College of Charleston, Charleston, SC, 29407, USA
| | - Yiying Chin
- Department of Physics, National Chung Cheng University, Chiayi, 62102, Taiwan
| | - Zhiwei Hu
- Max Planck Institute for Chemical Physics of Solids, Nothnitzer Strasse 40, 01187, Dresden, Germany
| | - Xiaoqing Huang
- State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, 361005, China
| | - Qi Shao
- College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Jiangsu, 215123, China
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Yang M, Li B, Li S, Dong Q, Huang Z, Zheng S, Fang Y, Zhou G, Chen X, Zhu X, Li T, Chi M, Wang G, Hu L, Ren ZJ. Highly Selective Electrochemical Nitrate to Ammonia Conversion by Dispersed Ru in a Multielement Alloy Catalyst. Nano Lett 2023; 23:7733-7742. [PMID: 37379097 DOI: 10.1021/acs.nanolett.3c01978] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/29/2023]
Abstract
Electrochemical reduction of nitrate to ammonia (NH3) converts an environmental pollutant to a critical nutrient. However, current electrochemical nitrate reduction operations based on monometallic and bimetallic catalysts are limited in NH3 selectivity and catalyst stability, especially in acidic environments. Meanwhile, catalysts with dispersed active sites generally exhibit a higher atomic utilization and distinct activity. Herein, we report a multielement alloy nanoparticle catalyst with dispersed Ru (Ru-MEA) with other synergistic components (Cu, Pd, Pt). Density functional theory elucidated the synergy effect of Ru-MEA than Ru, where a better reactivity (NH3 partial current density of -50.8 mA cm-2) and high NH3 faradaic efficiency (93.5%) is achieved in industrially relevant acidic wastewater. In addition, the Ru-MEA catalyst showed good stability (e.g., 19.0% decay in FENH3 in three hours). This work provides a potential systematic and efficient catalyst discovery process that integrates a data-guided catalyst design and novel catalyst synthesis for a range of applications.
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Affiliation(s)
- Meiqi Yang
- Department of Civil and Environmental Engineering and Andlinger Center for Energy and the Environment, Princeton University, Princeton, New Jersey 08544, United States
| | - Boyang Li
- Department of Mechanical Engineering and Materials Science, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
| | - Shuke Li
- Department of Materials Science and Engineering, University of Maryland, College Park, Maryland 20742, United States
| | - Qi Dong
- Department of Materials Science and Engineering, University of Maryland, College Park, Maryland 20742, United States
| | - Zhennan Huang
- Department of Materials Science and Engineering, University of Maryland, College Park, Maryland 20742, United States
| | - Sunxiang Zheng
- Department of Civil and Environmental Engineering and Andlinger Center for Energy and the Environment, Princeton University, Princeton, New Jersey 08544, United States
| | - Ying Fang
- Department of Mechanical Engineering and Materials Science, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
| | - Guangye Zhou
- Department of Civil and Environmental Engineering and Andlinger Center for Energy and the Environment, Princeton University, Princeton, New Jersey 08544, United States
| | - Xi Chen
- Department of Civil and Environmental Engineering and Andlinger Center for Energy and the Environment, Princeton University, Princeton, New Jersey 08544, United States
| | - Xiaobo Zhu
- Department of Civil and Environmental Engineering and Andlinger Center for Energy and the Environment, Princeton University, Princeton, New Jersey 08544, United States
| | - Tangyuan Li
- Department of Materials Science and Engineering, University of Maryland, College Park, Maryland 20742, United States
| | - Miaofang Chi
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37932, United States
| | - Guofeng Wang
- Department of Mechanical Engineering and Materials Science, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
| | - Liangbing Hu
- Department of Materials Science and Engineering, University of Maryland, College Park, Maryland 20742, United States
| | - Zhiyong Jason Ren
- Department of Civil and Environmental Engineering and Andlinger Center for Energy and the Environment, Princeton University, Princeton, New Jersey 08544, United States
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Abdella S, Abid F, Youssef SH, Kim S, Afinjuomo F, Malinga C, Song Y, Garg S. pH and its applications in targeted drug delivery. Drug Discov Today 2023; 28:103414. [PMID: 36273779 DOI: 10.1016/j.drudis.2022.103414] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Revised: 08/09/2022] [Accepted: 10/17/2022] [Indexed: 02/02/2023]
Abstract
Physiologic pH is vital for the normal functioning of tissues and varies in different parts of the body. The varying pH of the body has been exploited to design pH-sensitive smart oral, transdermal and vaginal drug delivery systems (DDS). The DDS demonstrated promising results in hard-to-treat diseases such as cancer and Helicobacter pylori infection. In some cases, a change in pH of tissues or body fluids has also been employed as a useful diagnostic biomarker. This paper aims to comprehensively review the development and applications of pH-sensitive DDS as well as recent advances in the field.
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Affiliation(s)
- Sadikalmahdi Abdella
- Centre for Pharmaceutical Innovation (CPI), University of South Australia, Adelaide, SA 5000, Australia; Department of Pharmacology and Clinical Pharmacy, College of Health Sciences, Addis Ababa University, Zambia St, Addis Ababa, Ethiopia
| | - Fatima Abid
- Centre for Pharmaceutical Innovation (CPI), University of South Australia, Adelaide, SA 5000, Australia
| | - Souha H Youssef
- Centre for Pharmaceutical Innovation (CPI), University of South Australia, Adelaide, SA 5000, Australia
| | - Sangseo Kim
- Centre for Pharmaceutical Innovation (CPI), University of South Australia, Adelaide, SA 5000, Australia
| | - Franklin Afinjuomo
- Centre for Pharmaceutical Innovation (CPI), University of South Australia, Adelaide, SA 5000, Australia
| | - Constance Malinga
- Centre for Pharmaceutical Innovation (CPI), University of South Australia, Adelaide, SA 5000, Australia
| | - Yunmei Song
- Centre for Pharmaceutical Innovation (CPI), University of South Australia, Adelaide, SA 5000, Australia
| | - Sanjay Garg
- Centre for Pharmaceutical Innovation (CPI), University of South Australia, Adelaide, SA 5000, Australia.
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6
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Santos RF, Oliveira BMC, Ferreira PJ, Vieira MF. The Effect of Ultrasonic Agitation on the Seedless Growth of Cu on Ru-W Thin Films. Materials (Basel) 2022; 16:167. [PMID: 36614506 PMCID: PMC9822143 DOI: 10.3390/ma16010167] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/14/2022] [Revised: 12/16/2022] [Accepted: 12/19/2022] [Indexed: 06/17/2023]
Abstract
Ru attracted considerable attention as a candidate to replace TaN as a diffusion barrier layer for Cu interconnect metallisation. The addition of W improves the diffusion barrier properties of Ru but appears to weaken the adhesion strength between the barrier and Cu and the direct (seedless) electroplatability behaviour. Although Cu can be directly electroplated on near equimolar Ru-W thin films, no complete substrate coverage is obtained. The understanding of Cu electrocrystallisation on Ru−W is essential to develop methods of fabricating thin, continuous, and well adherent films for advanced interconnect metallisation, where Ru−W thin films could be used as diffusion barriers. This work studies the effect of ultrasonic agitation on the growth of Cu films electroplated on Ru−W, namely on the impact on substrate coverage. Film structure, morphology and chemical composition were evaluated by digital and scanning and transmission electron microscopies, and X-ray diffraction. The results show that Cu particles decrease with increasing current density, but when no electrolyte agitation is applied, substrate coverage is incomplete in the central region, with openings around larger Cu particles, regardless of current density. Under ultrasonic agitation, substrate coverage is remarkably improved. An active particle detachment mechanism is proposed as responsible for attaining improved substrate coverage, only possible at intermediate current density. Lower current densities promote growth over nucleation, whereas higher currents result in extensive hydrogen reduction/formation. Ultrasonic agitation also enhances a preferential Cu growth along <111> direction.
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Affiliation(s)
- Rúben F. Santos
- Department of Metallurgical and Materials Engineering, University of Porto, 4200-465 Porto, Portugal
- LAETA/INEGI—Institute of Science and Innovation in Mechanical and Industrial Engineering, 4200-465 Porto, Portugal
| | - Bruno M. C. Oliveira
- Department of Metallurgical and Materials Engineering, University of Porto, 4200-465 Porto, Portugal
- LAETA/INEGI—Institute of Science and Innovation in Mechanical and Industrial Engineering, 4200-465 Porto, Portugal
| | - Paulo J. Ferreira
- International Iberian Nanotechnology Laboratory, 4715-330 Braga, Portugal
- Materials Science and Engineering Program, University of Texas at Austin, Austin, TX 78712, USA
- Mechanical Engineering Department and IDMEC, IST, University of Lisbon, 1749-016 Lisbon, Portugal
| | - Manuel F. Vieira
- Department of Metallurgical and Materials Engineering, University of Porto, 4200-465 Porto, Portugal
- LAETA/INEGI—Institute of Science and Innovation in Mechanical and Industrial Engineering, 4200-465 Porto, Portugal
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Zhang Y, Jin T, Zhu W, Pandya M, Gopinathan G, Allen M, Reed D, Keiderling T, Liao X, Diekwisch TGH. Highly acidic pH facilitates enamel protein self-assembly, apatite crystal growth and enamel protein interactions in the early enamel matrix. Front Physiol 2022; 13:1019364. [PMID: 36569763 PMCID: PMC9772882 DOI: 10.3389/fphys.2022.1019364] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2022] [Accepted: 11/22/2022] [Indexed: 12/13/2022] Open
Abstract
Tooth enamel develops within a pH sensitive amelogenin-rich protein matrix. The purpose of the present study is to shed light on the intimate relationship between enamel matrix pH, enamel protein self-assembly, and enamel crystal growth during early amelogenesis. Universal indicator dye staining revealed highly acidic pH values (pH 3-4) at the exocytosis site of secretory ameloblasts. When increasing the pH of an amelogenin solution from pH 5 to pH 7, there was a gradual increase in subunit compartment size from 2 nm diameter subunits at pH 5 to a stretched configuration at pH6 and to 20 nm subunits at pH 7. HSQC NMR spectra revealed that the formation of the insoluble amelogenin self-assembly structure at pH6 was critically mediated by at least seven of the 11 histidine residues of the amelogenin coil domain (AA 46-117). Comparing calcium crystal growth on polystyrene plates, crystal length was more than 20-fold elevated at pH 4 when compared to crystals grown at pH 6 or pH 7. To illustrate the effect of pH on enamel protein self-assembly at the site of initial enamel formation, molar teeth were immersed in phosphate buffer at pH4 and pH7, resulting in the formation of intricate berry tree-like assemblies surrounding initial enamel crystal assemblies at pH4 that were not evident at pH7 nor in citrate buffer. Amelogenin and ameloblastin enamel proteins interacted at the secretory ameloblast pole and in the initial enamel layer, and co-immunoprecipitation studies revealed that this amelogenin/ameloblastin interaction preferentially takes place at pH 4-pH 4.5. Together, these studies highlight the highly acidic pH of the very early enamel matrix as an essential contributing factor for enamel protein structure and self-assembly, apatite crystal growth, and enamel protein interactions.
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Affiliation(s)
- Youbin Zhang
- Department of Oral Biology, University of Illinois at Chicago, Dallas, Illinois, United States
| | - Tianquan Jin
- Department of Oral Biology, University of Illinois at Chicago, Dallas, Illinois, United States
| | - Weiying Zhu
- Department of Chemistry, University of Illinois at Chicago, Chicago, Illinois, United States
| | - Mirali Pandya
- Center for Craniofacial Research and Diagnosis, Texas A and M College of Dentistry, Dallas, Texas, United States
| | - Gokul Gopinathan
- Center for Craniofacial Research and Diagnosis, Texas A and M College of Dentistry, Dallas, Texas, United States
| | - Michael Allen
- Department of Medicine, University of Chicago, Chicago, Illinois, United States
| | - David Reed
- Department of Oral Biology, University of Illinois at Chicago, Dallas, Illinois, United States
| | - Timothy Keiderling
- Department of Chemistry, University of Illinois at Chicago, Chicago, Illinois, United States,*Correspondence: Timothy Keiderling, ; Xiubei Liao, ; Thomas G. H. Diekwisch,
| | - Xiubei Liao
- Department of Biochemistry, University of Illinois at Chicago, Chicago, Illinois, United States,*Correspondence: Timothy Keiderling, ; Xiubei Liao, ; Thomas G. H. Diekwisch,
| | - Thomas G. H. Diekwisch
- Department of Oral Biology, University of Illinois at Chicago, Dallas, Illinois, United States,Center for Craniofacial Research and Diagnosis, Texas A and M College of Dentistry, Dallas, Texas, United States,*Correspondence: Timothy Keiderling, ; Xiubei Liao, ; Thomas G. H. Diekwisch,
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Sim P, Strudwick XL, Song Y, Cowin AJ, Garg S. Influence of Acidic pH on Wound Healing In Vivo: A Novel Perspective for Wound Treatment. Int J Mol Sci 2022; 23:13655. [PMID: 36362441 PMCID: PMC9658872 DOI: 10.3390/ijms232113655] [Citation(s) in RCA: 26] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2022] [Revised: 11/04/2022] [Accepted: 11/04/2022] [Indexed: 07/30/2023] Open
Abstract
There has been little understanding of acidification functionality in wound healing, highlighting the need to study the efficacy of wound acidification on wound closure and cellular activity in non-infected wounds. This study is focused on establishing the healing potential of wound acidification in non-infected wounds. Acidic buffers, constituting either phosphoric or citric acid, were employed to modify the physiological pH of non-infected full-thickness excisional murine wounds. Acidification of the wound by acidic buffers was found to be an effective strategy to improve wound healing. A significant improvement in wound healing parameters was observed as early as 2 days post-treatment with acidic buffers compared to controls, with faster rate of epithelialization, wound closure and higher levels of collagen at day 7. pH is shown to play a role in mediating the rate of wound healing, with acidic buffers formulated at pH 4 observed to stimulate faster recovery of wounded tissues than pH 6 buffers. Our study shows the importance of maintaining an acidic wound microenvironment at pH 4, which could be a potential therapeutic strategy for wound management.
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Affiliation(s)
- Pivian Sim
- Centre for Pharmaceutical Innovation (CPI), Clinical and Health Sciences, University of South Australia, Adelaide, SA 5000, Australia
| | - Xanthe L. Strudwick
- Regenerative Medicine, Future Industries Institute, University of South Australia, Adelaide, SA 5095, Australia
| | - YunMei Song
- Centre for Pharmaceutical Innovation (CPI), Clinical and Health Sciences, University of South Australia, Adelaide, SA 5000, Australia
| | - Allison J. Cowin
- Regenerative Medicine, Future Industries Institute, University of South Australia, Adelaide, SA 5095, Australia
| | - Sanjay Garg
- Centre for Pharmaceutical Innovation (CPI), Clinical and Health Sciences, University of South Australia, Adelaide, SA 5000, Australia
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9
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Lo SK, Uhl L, Lee J, Cavanagh A, Henriksen MDL. Acidic chemical corneal ulceration secondary to nail polish spill in a puppy. J Vet Emerg Crit Care (San Antonio) 2022; 32:507-511. [PMID: 35001484 DOI: 10.1111/vec.13181] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Revised: 07/10/2020] [Accepted: 08/16/2020] [Indexed: 12/01/2022]
Abstract
PURPOSE To describe the treatment of an acidic chemical corneal ulceration in a puppy secondary to nail polish spilling on and adhering to the cornea. CASE SUMMARY A 12-week-old neutered male Australian Shepherd mix dog was presented to Colorado State University Veterinary Teaching Hospital's (CSU-VTH) Emergency and Urgent Care service acutely after exposure to nail polish spilling on the left eye (OS). Initial ophthalmic examination revealed nail polish adhered to approximately 80% of the cornea with moderate diffuse corneal edema and chemosis, and green nail polish adhered to the skin and fur of the periocular area. Copious flushing with eye wash was performed, but no areas of reduced nail polish adherence were noted. The patient was treated with 1 drop of topical ofloxacin 0.3% ophthalmic solution OS and hospitalized overnight, receiving hyaluronic acid ophthalmic lubrication every hour OS. The treatment plan was carried out for 6 h until time of transfer. In the morning, CSU-VTH's Ophthalmology service removed a nonadhered nail polish plaque in 1 piece using Bishop-Harmon tissue forceps. Following removal, a superficial ulcer secondary to an acidic chemical burn covering 100% of the corneal surface was noted, as well as moderate diffuse corneal edema. Following topical treatment for 8 days, the superficial ulcer healed completely, with no significant long-term consequences. UNIQUE INFORMATION PROVIDED This is the first report of management of an acidic chemical corneal ulceration secondary to nail polish spill in a puppy. Early assessment and vigilance in treatment was essential for a good prognosis and outcome.
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Affiliation(s)
- Stephanie K Lo
- Ophthalmology Service, Department of Clinical Sciences, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, Colorado, USA
| | - Lisa Uhl
- Ophthalmology Service, Department of Clinical Sciences, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, Colorado, USA
| | - Jack Lee
- Emergency and Critical Care Service, Department of Clinical Sciences, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, Colorado, USA
| | - Amanda Cavanagh
- Emergency and Critical Care Service, Department of Clinical Sciences, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, Colorado, USA
| | - Michala de Linde Henriksen
- Ophthalmology Service, Department of Clinical Sciences, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, Colorado, USA
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Santos RF, Oliveira BMC, Savaris LCG, Ferreira PJ, Vieira MF. Seedless Cu Electroplating on Ru-W Thin Films for Metallisation of Advanced Interconnects. Int J Mol Sci 2022; 23:1891. [PMID: 35163817 DOI: 10.3390/ijms23031891] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2021] [Revised: 02/02/2022] [Accepted: 02/04/2022] [Indexed: 02/03/2023] Open
Abstract
For decades, Ta/TaN has been the industry standard for a diffusion barrier against Cu in interconnect metallisation. The continuous miniaturisation of transistors and interconnects into the nanoscale are pushing conventional materials to their physical limits and creating the need to replace them. Binary metallic systems, such as Ru-W, have attracted considerable attention as possible replacements due to a combination of electrical and diffusion barrier properties and the capability of direct Cu electroplating. The process of Cu electrodeposition on Ru-W is of fundamental importance in order to create thin, continuous, and adherent films for advanced interconnect metallisation. This work investigates the effects of the current density and application method on the electro-crystallisation behaviour of Cu. The film structure, morphology, and chemical composition were assessed by digital microscopy, atomic force microscopy, scanning and transmission electron microscopies, energy-dispersive X-ray spectroscopy, and X-ray diffraction. The results show that it was possible to form a thin Cu film on Ru-W with interfacial continuity for current densities higher than 5 mA·cm−2; however, the substrate regions around large Cu particles remained uncovered. Pulse-reverse current application appears to be more beneficial than direct current as it decreased the average Cu particle size.
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11
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Sun Y, Hu L, Yang P, Zhang M, Wang X, Xiao H, Qiao C, Wang J, Luo L, Feng J, Zheng Y, Wang Y, Shi Y, Chen G. pH Low Insertion Peptide-Modified Programmed Cell Death-Ligand 1 Potently Suppresses T-Cell Activation Under Acidic Condition. Front Immunol 2021; 12:794226. [PMID: 35003115 PMCID: PMC8733706 DOI: 10.3389/fimmu.2021.794226] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2021] [Accepted: 12/01/2021] [Indexed: 11/13/2022] Open
Abstract
Programmed cell death-ligand 1 (PD-L1)/PD-1 axis is critical for maintenance of immune homeostasis by limiting overactivation of effector T-cell responses. The impairment of PD-L1/PD-1 signals play an important role in the pathogenesis of inflammatory diseases, making this pathway an ideal target for novel therapeutics to induce immune tolerance. Given weakly acidic environment as a putative hallmark of inflammation, in this study we designed a new cargo by linking the ectodomain of murine PD-L1 to the N terminus of pHLIPs, a low pH-responding and membrane-insertion peptide, and demonstrated its potent immune-suppressive activity. Specifically, PD-L1-pHLIP spanned the cellular membrane and perfectly recognized its ligand PD-1 in acidic buffer. Immobile PD-L1-pHLIP actively inhibited T-cell proliferation and IFN-γ production. Importantly, soluble PD-L1-pHLIP retained its function to dampen T-cell responses under acidic condition instead of neutral aqueous solution. Overall, these data suggest that PD-L1-pHLIP has potentials to be a novel therapeutic avenue for T-cell-mediated inflammatory diseases.
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Affiliation(s)
- Ying Sun
- Inner Mongolia Key Lab of Molecular Biology, School of Basic Medical Sciences, Inner Mongolia Medical University, Hohhot, China
- State Key Laboratory of Toxicology and Medical Countermeasures, Institute of Pharmacology and Toxicology, Beijing, China
| | - Linhan Hu
- Inner Mongolia Key Lab of Molecular Biology, School of Basic Medical Sciences, Inner Mongolia Medical University, Hohhot, China
- State Key Laboratory of Toxicology and Medical Countermeasures, Institute of Pharmacology and Toxicology, Beijing, China
| | - Peng Yang
- Inner Mongolia Key Lab of Molecular Biology, School of Basic Medical Sciences, Inner Mongolia Medical University, Hohhot, China
| | - Min Zhang
- State Key Laboratory of Toxicology and Medical Countermeasures, Institute of Pharmacology and Toxicology, Beijing, China
| | - Xinwei Wang
- Inner Mongolia Key Lab of Molecular Biology, School of Basic Medical Sciences, Inner Mongolia Medical University, Hohhot, China
| | - He Xiao
- State Key Laboratory of Toxicology and Medical Countermeasures, Institute of Pharmacology and Toxicology, Beijing, China
| | - Chunxia Qiao
- State Key Laboratory of Toxicology and Medical Countermeasures, Institute of Pharmacology and Toxicology, Beijing, China
| | - Jing Wang
- State Key Laboratory of Toxicology and Medical Countermeasures, Institute of Pharmacology and Toxicology, Beijing, China
| | - Longlong Luo
- State Key Laboratory of Toxicology and Medical Countermeasures, Institute of Pharmacology and Toxicology, Beijing, China
| | - Jiannan Feng
- State Key Laboratory of Toxicology and Medical Countermeasures, Institute of Pharmacology and Toxicology, Beijing, China
| | - Yuanqiang Zheng
- Inner Mongolia Key Lab of Molecular Biology, School of Basic Medical Sciences, Inner Mongolia Medical University, Hohhot, China
| | - Yi Wang
- Department of Hematology, The Fifth Medical Center, Chinese PLA General Hospital, Beijing, China
| | - Yanchun Shi
- Inner Mongolia Key Lab of Molecular Biology, School of Basic Medical Sciences, Inner Mongolia Medical University, Hohhot, China
| | - Guojiang Chen
- State Key Laboratory of Toxicology and Medical Countermeasures, Institute of Pharmacology and Toxicology, Beijing, China
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12
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Wagh NK, Kim DH, Kim SH, Shinde SS, Lee JH. Heuristic Iron-Cobalt-Mediated Robust pH-Universal Oxygen Bifunctional Lusters for Reversible Aqueous and Flexible Solid-State Zn-Air Cells. ACS Nano 2021; 15:14683-14696. [PMID: 34412470 DOI: 10.1021/acsnano.1c04471] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Rechargeable aqueous zinc-air cells (ZACs) promise an extremely safe and high energy technology. However, they are still significantly limited by sluggish electrochemical kinetics and irreversibility originating from the parasitic reactions of the bifunctional catalysts and electrolytes. Here, we report the preferential in situ building of interfacial structures featuring the edge sites constituted by FeCo single/dual atoms with the integration of Co sites in the nitrogenized graphitic carbon frameworks (FeCo SAs@Co/N-GC) by electronic structure modulation approach. Compared to commercial Pt/C and RuO2, FeCo SAs@Co/N-GC reveals exceptional electrochemical performance, reversible redox kinetics, and durability toward oxygen reduction and evolution reactions under universal pH environments, i.e., alkaline, neutral, and acidic, due to synergistic effect at interfaces and preferred charge/mass transfer. The aqueous (alkaline, nonalkaline, and acidic electrolytes) ZACs constructed with a FeCo SAs@Co/N-GC cathode tolerate stable operations, have significant reversibility, and have the highest energy densities, outperforming those of noble metal counterparts and state-of-the-art ZACs in the ambient atmosphere. Additionally, flexible solid-state ZACs demonstrate excellent mechanical and electrochemical performances with a highest power density of 186 mW cm-2, specific capacity of 817 mAh gZn-1, energy density of 1017 Wh kgZn-1, and cycle life >680 cycles with extremely harsh operating conditions, which illustrates the great potential of triphasic catalyst for green energy storage technologies.
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Affiliation(s)
- Nayantara K Wagh
- Department of Materials Science and Chemical Engineering, Hanyang University, Ansan, Gyeonggi-do 15588, Republic of Korea
| | - Dong-Hyung Kim
- Department of Materials Science and Chemical Engineering, Hanyang University, Ansan, Gyeonggi-do 15588, Republic of Korea
| | - Sung-Hae Kim
- Department of Materials Science and Chemical Engineering, Hanyang University, Ansan, Gyeonggi-do 15588, Republic of Korea
| | - Sambhaji S Shinde
- Department of Materials Science and Chemical Engineering, Hanyang University, Ansan, Gyeonggi-do 15588, Republic of Korea
| | - Jung-Ho Lee
- Department of Materials Science and Chemical Engineering, Hanyang University, Ansan, Gyeonggi-do 15588, Republic of Korea
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13
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Santos RF, Oliveira BMC, Chícharo A, Alpuim P, Ferreira PJ, Simões S, Viana F, Vieira MF. Seedless Cu Electroplating on Co-W Thin Films in Low pH Electrolyte: Early Stages of Formation. Nanomaterials (Basel) 2021; 11:nano11081914. [PMID: 34443745 PMCID: PMC8398599 DOI: 10.3390/nano11081914] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Revised: 07/19/2021] [Accepted: 07/20/2021] [Indexed: 11/25/2022]
Abstract
The use of Ta/TaN barrier bilayer systems in electronic applications has been ubiquitous over the last decade. Alternative materials such as Co-W or Ru-W alloys have gathered interest as possible replacements due to their conjugation of favourable electrical properties and barrier layer efficiency at reduced thicknesses while enabling seedless Cu electroplating. The microstructure, morphology, and electrical properties of Cu films directly electrodeposited onto Co-W or Ru-W are important to assess, concomitant with their ability to withstand the electroplating baths/conditions. This work investigates the effects of the current application method and pH value of the electroplating solution on the electrocrystallisation behaviour of Cu deposited onto a Co-W barrier layer. The film structure, morphology, and chemical composition were studied by X-ray diffraction, scanning electron microscopy and atomic force microscopy, as well as photoelectron spectroscopy. The results show that the electrolyte solution at pH 1.8 is incapable of creating a compact Cu film over the Co-W layer in either pulsed or direct-current modes. At higher pH, a continuous film is formed. A mechanism is proposed for the nucleation and growth of Cu on Co-W, where a balance between Cu nucleation, growth, and preferential Co dissolution dictates the substrate area coverage and compactness of the electrodeposited films.
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Affiliation(s)
- Rúben F. Santos
- Department of Metallurgical and Materials Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal; (B.M.C.O.); (S.S.); (F.V.); (M.F.V.)
- LAETA/INEGI–Institute of Science and Innovation in Mechanical and Industrial Engineering, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal
- Correspondence:
| | - Bruno M. C. Oliveira
- Department of Metallurgical and Materials Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal; (B.M.C.O.); (S.S.); (F.V.); (M.F.V.)
- LAETA/INEGI–Institute of Science and Innovation in Mechanical and Industrial Engineering, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal
| | - Alexandre Chícharo
- International Iberian Nanotechnology Laboratory, Av. Mestre José Veiga, 4715-330 Braga, Portugal; (A.C.); (P.A.); (P.J.F.)
| | - Pedro Alpuim
- International Iberian Nanotechnology Laboratory, Av. Mestre José Veiga, 4715-330 Braga, Portugal; (A.C.); (P.A.); (P.J.F.)
- Centre of Physics, University of Minho, 4710-057 Braga, Portugal
| | - Paulo J. Ferreira
- International Iberian Nanotechnology Laboratory, Av. Mestre José Veiga, 4715-330 Braga, Portugal; (A.C.); (P.A.); (P.J.F.)
- Materials Science and Engineering Program, University of Texas at Austin, Austin, TX 78712, USA
- Mechanical Engineering Department and IDMEC, IST University of Lisbon, Av. Rovisco Pais, 1049-001 Lisboa, Portugal
| | - Sónia Simões
- Department of Metallurgical and Materials Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal; (B.M.C.O.); (S.S.); (F.V.); (M.F.V.)
- LAETA/INEGI–Institute of Science and Innovation in Mechanical and Industrial Engineering, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal
| | - Filomena Viana
- Department of Metallurgical and Materials Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal; (B.M.C.O.); (S.S.); (F.V.); (M.F.V.)
- LAETA/INEGI–Institute of Science and Innovation in Mechanical and Industrial Engineering, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal
| | - Manuel F. Vieira
- Department of Metallurgical and Materials Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal; (B.M.C.O.); (S.S.); (F.V.); (M.F.V.)
- LAETA/INEGI–Institute of Science and Innovation in Mechanical and Industrial Engineering, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal
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14
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Tu VY, Ayari A, O’Connor RS. Beyond the Lactate Paradox: How Lactate and Acidity Impact T Cell Therapies against Cancer. Antibodies (Basel) 2021; 10:antib10030025. [PMID: 34203136 PMCID: PMC8293081 DOI: 10.3390/antib10030025] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Revised: 06/14/2021] [Accepted: 06/22/2021] [Indexed: 11/16/2022] Open
Abstract
T cell therapies, including CAR T cells, have proven more effective in hematologic malignancies than solid tumors, where the local metabolic environment is distinctly immunosuppressive. In particular, the acidic and hypoxic features of the tumor microenvironment (TME) present a unique challenge for T cells. Local metabolism is an important consideration for activated T cells as they undergo bursts of migration, proliferation and differentiation in hostile soil. Tumor cells and activated T cells both produce lactic acid at high rates. The role of lactic acid in T cell biology is complex, as lactate is an often-neglected carbon source that can fuel TCA anaplerosis. Circulating lactate is also an important means to regulate redox balance. In hypoxic tumors, lactate is immune-suppressive. Here, we discuss how intrinsic- (T cells) as well as extrinsic (tumor cells and micro-environmental)-derived metabolic factors, including lactate, suppress the ability of antigen-specific T cells to eradicate tumors. Finally, we introduce recent discoveries that target the TME in order to potentiate T cell-based therapies against cancer.
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Affiliation(s)
- Violet Y. Tu
- Center for Cellular Immunotherapies, Perelman School of Medicine of the University of Pennsylvania, Philadelphia, PA 19104, USA;
- Department of Biological Physics, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Asma Ayari
- Nucleus Biologics, LLC., San Diego, CA 92127, USA;
| | - Roddy S. O’Connor
- Center for Cellular Immunotherapies, Perelman School of Medicine of the University of Pennsylvania, Philadelphia, PA 19104, USA;
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine of the University of Pennsylvania, Philadelphia, PA 19104, USA
- Correspondence:
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15
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Reuss AM, Groos D, Buchfelder M, Savaskan N. The Acidic Brain-Glycolytic Switch in the Microenvironment of Malignant Glioma. Int J Mol Sci 2021; 22:5518. [PMID: 34073734 DOI: 10.3390/ijms22115518] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2021] [Revised: 05/16/2021] [Accepted: 05/19/2021] [Indexed: 12/15/2022] Open
Abstract
Malignant glioma represents a fatal disease with a poor prognosis and development of resistance mechanisms against conventional therapeutic approaches. The distinct tumor zones of this heterogeneous neoplasm develop their own microenvironment, in which subpopulations of cancer cells communicate. Adaptation to hypoxia in the center of the expanding tumor mass leads to the glycolytic and angiogenic switch, accompanied by upregulation of different glycolytic enzymes, transporters, and other metabolites. These processes render the tumor microenvironment more acidic, remodel the extracellular matrix, and create energy gradients for the metabolic communication between different cancer cells in distinct tumor zones. Escape mechanisms from hypoxia-induced cell death and energy deprivation are the result. The functional consequences are more aggressive and malignant behavior with enhanced proliferation and survival, migration and invasiveness, and the induction of angiogenesis. In this review, we go from the biochemical principles of aerobic and anaerobic glycolysis over the glycolytic switch, regulated by the key transcription factor hypoxia-inducible factor (HIF)-1α, to other important metabolic players like the monocarboxylate transporters (MCTs)1 and 4. We discuss the metabolic symbiosis model via lactate shuttling in the acidic tumor microenvironment and highlight the functional consequences of the glycolytic switch on glioma malignancy. Furthermore, we illustrate regulation by micro ribonucleic acids (miRNAs) and the connection between isocitrate dehydrogenase (IDH) mutation status and glycolytic metabolism. Finally, we give an outlook about the diagnostic and therapeutic implications of the glycolytic switch and the relation to tumor immunity in malignant glioma.
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16
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Usuelli M, Meyer T, Mezzenga R, Mitsi M. VEGF and VEGFR2 bind to similar pH-sensitive sites on fibronectin, exposed by heparin-mediated conformational changes. J Biol Chem 2021; 296:100584. [PMID: 33771558 PMCID: PMC8102423 DOI: 10.1016/j.jbc.2021.100584] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2020] [Revised: 03/16/2021] [Accepted: 03/22/2021] [Indexed: 02/03/2023] Open
Abstract
Physical interactions between vascular endothelial growth factor (VEGF), a central player in blood endothelial cell biology, and fibronectin, a major fibrillar protein of the extracellular matrix, are important determinants of angiogenic activity in health and disease. Conditions signaling the need for new blood vessel growth, such as hypoxia and low extracellular pH, increase VEGF–fibronectin interactions. These interactions can be further fine-tuned through changes in the availability of the VEGF-binding sites on fibronectin, regulated by conformational changes induced by heparin and heparan sulfate chains within the extracellular matrix. These interactions may alter VEGF bioavailability, generate gradients, or alter the way VEGF is recognized by and activates its cell-surface receptors. Here, using equilibrium and kinetic studies, we discovered that fibronectin can also interact with the extracellular domain of the VEGF receptor 2 (VEGFR2). The VEGFR2-binding sites on fibronectin show great similarity to the VEGF-binding sites, as they were also exposed upon heparin-induced conformational changes in fibronectin, and the interaction was enhanced at acidic pH. Kinetic parameters and affinities for VEGF and VEGFR2 binding to fibronectin were determined by surface plasmon resonance measurements, revealing two populations of fibronectin-binding sites for each molecule. Our data also suggest that a VEGF/VEGFR2/fibronectin triple complex may be formed by VEGF or VEGFR2 first binding to fibronectin and subsequently recruiting the third binding partner. The formation of such a complex may lead to the activation of distinct angiogenic signaling pathways, offering new possibilities for clinical applications that target angiogenesis.
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Affiliation(s)
- Mattia Usuelli
- Laboratory of Food and Soft Materials, Department of Health Sciences and Technology, ETH Zurich, Zurich, Switzerland
| | - Timmy Meyer
- Laboratory of Food and Soft Materials, Department of Health Sciences and Technology, ETH Zurich, Zurich, Switzerland
| | - Raffaele Mezzenga
- Laboratory of Food and Soft Materials, Department of Health Sciences and Technology, ETH Zurich, Zurich, Switzerland.
| | - Maria Mitsi
- Laboratory of Food and Soft Materials, Department of Health Sciences and Technology, ETH Zurich, Zurich, Switzerland.
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17
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Kittl M, Winklmayr M, Helm K, Lettner J, Gaisberger M, Ritter M, Jakab M. Acid- and Volume-Sensitive Chloride Currents in Human Chondrocytes. Front Cell Dev Biol 2020; 8:583131. [PMID: 33282866 PMCID: PMC7691427 DOI: 10.3389/fcell.2020.583131] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Accepted: 10/13/2020] [Indexed: 12/18/2022] Open
Abstract
Chondrocytes face extreme alterations of extracellular osmolarity and pH, which force them to appropriately regulate their cell volume (CV) and cellular pH. Perturbations of these mechanisms lead to chondrocyte death and ultimately to osteoarthritis (OA), the most common chronic joint diseases worldwide. OA hallmarks are altered cartilage hydration and severe fluid acidification. Impaired CV regulation and acidotoxicity contribute to disease progression and volume-sensitive anion channels are upregulated in OA. This study assessed the effect of hypotonicity and extracellular acidification on chondrocyte Cl– conductances and CV regulation. Cl– currents and membrane potentials were measured in human C28/I2 cells and primary human chondrocytes using the patch clamp technique. Intracellular pH was assessed by BCECF fluorescence, CV measurements were performed using the Coulter method, and cell viability/cell death by a resazurin assay. Hypotonic cell swelling caused activation of a volume-sensitive outwardly rectifying (VSOR) Cl– current followed by a regulatory volume decrease (RVD), which was attenuated by the Cl– channel blocker DCPIB. Extracellular, but not intracellular acidification to pH ≤ 5.0 elicited an acid-sensitive outwardly rectifying (ASOR) Cl– conductance. Activation of either current depolarized the cell membrane potential. Under simultaneous hypotonic and acidic stimulation, VSOR and ASOR currents transiently coactivated, giving rise to a mixed current phenotype. Over time the VSOR current gradually vanished and the residual conductance showed a pure ASOR current phenotype. Extracellular acidification caused an isotonic CV gain and a complete suppression of RVD under hypotonic conditions. The results suggest that deactivation of the VSOR current under acidic conditions impairs CV regulation in chondrocytes, which is likely to compromise chondrocyte viability.
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Affiliation(s)
- Michael Kittl
- Institute of Physiology and Pathophysiology, Paracelsus Medical University, Salzburg, Austria
| | - Martina Winklmayr
- Ludwig Boltzmann Institute for Arthritis and Rehabilitation, Paracelsus Medical University, Salzburg, Austria
| | - Katharina Helm
- Institute of Physiology and Pathophysiology, Paracelsus Medical University, Salzburg, Austria
| | - Johannes Lettner
- Institute of Physiology and Pathophysiology, Paracelsus Medical University, Salzburg, Austria
| | - Martin Gaisberger
- Institute of Physiology and Pathophysiology, Paracelsus Medical University, Salzburg, Austria.,Ludwig Boltzmann Institute for Arthritis and Rehabilitation, Paracelsus Medical University, Salzburg, Austria.,Gastein Research Institute, Paracelsus Medical University, Salzburg, Austria
| | - Markus Ritter
- Institute of Physiology and Pathophysiology, Paracelsus Medical University, Salzburg, Austria.,Ludwig Boltzmann Institute for Arthritis and Rehabilitation, Paracelsus Medical University, Salzburg, Austria.,Gastein Research Institute, Paracelsus Medical University, Salzburg, Austria
| | - Martin Jakab
- Institute of Physiology and Pathophysiology, Paracelsus Medical University, Salzburg, Austria
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18
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Roberts BN, Chakravarty D, Gardner J, Ricke SC, Donaldson JR. Listeria monocytogenes Response to Anaerobic Environments. Pathogens 2020; 9:pathogens9030210. [PMID: 32178387 PMCID: PMC7157565 DOI: 10.3390/pathogens9030210] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2020] [Revised: 03/09/2020] [Accepted: 03/10/2020] [Indexed: 12/19/2022] Open
Abstract
Listeria monocytogenes is a Gram-positive facultative anaerobic bacterium that is responsible for the disease, listeriosis. It is particularly lethal in pregnant women, the fetus, the elderly and the immunocompromised. The pathogen survives and replicates over a wide range of temperatures (4 to 42 °C), pH, salt and oxygen concentrations. Because it can withstand various environments, L. monocytogenes is a major concern in food processing industries, especially in dairy products and ready-to-eat fruits, vegetables and deli meats. The environment in which the pathogen is exposed can influence the expression of virulence genes. For instance, studies have shown that variations in oxygen availability can impact resistance to stressors. Further investigation is needed to understand the essential genes required for the growth of L. monocytogenes in anaerobic conditions. Therefore, the purpose of this review is to highlight the data on L. monocytogenes under known environmental stresses in anaerobic environments and to focus on gaps in knowledge that may be advantageous to study in order to better understand the pathogenicity of the bacterium.
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Affiliation(s)
- Brandy N. Roberts
- Department of Biological Sciences, Mississippi State University, Mississippi State, MS 39762, USA;
| | - Damayanti Chakravarty
- Cell and Molecular Biology, The University of Southern Mississippi, Hattiesburg, MS 39406, USA; (D.C.); (J.C.G.III)
| | - J.C. Gardner
- Cell and Molecular Biology, The University of Southern Mississippi, Hattiesburg, MS 39406, USA; (D.C.); (J.C.G.III)
| | - Steven C. Ricke
- Center for Food Safety, Department of Food Science, University of Arkansas, Fayetteville, AR 72704, USA;
| | - Janet R. Donaldson
- Cell and Molecular Biology, The University of Southern Mississippi, Hattiesburg, MS 39406, USA; (D.C.); (J.C.G.III)
- Correspondence: ; Tel.: +1-601-206-6795
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19
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Efthimiou G, Tsiamis G, Typas MA, Pappas KM. Transcriptomic Adjustments of Staphylococcus aureus COL (MRSA) Forming Biofilms Under Acidic and Alkaline Conditions. Front Microbiol 2019; 10:2393. [PMID: 31681245 PMCID: PMC6813237 DOI: 10.3389/fmicb.2019.02393] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2019] [Accepted: 10/02/2019] [Indexed: 01/13/2023] Open
Abstract
Methicillin-resistant Staphylococcus aureus (MRSA) strains are important human pathogens and a significant health hazard for hospitals and the food industry. They are resistant to β-lactam antibiotics including methicillin and extremely difficult to treat. In this study, we show that the Staphylococcus aureus COL (MRSA) strain, with a known complete genome, can easily survive and grow under acidic and alkaline conditions (pH5 and pH9, respectively), both planktonically and as a biofilm. A microarray-based analysis of both planktonic and biofilm cells was performed under acidic and alkaline conditions showing that several genes are up- or down-regulated under different environmental conditions and growth modes. These genes were coding for transcription regulators, ion transporters, cell wall biosynthetic enzymes, autolytic enzymes, adhesion proteins and antibiotic resistance factors, most of which are associated with biofilm formation. These results will facilitate a better understanding of the physiological adjustments occurring in biofilm-associated S. aureus COL cells growing in acidic or alkaline environments, which will enable the development of new efficient treatment or disinfection strategies.
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Affiliation(s)
- Georgios Efthimiou
- Department of Genetics and Biotechnology, Faculty of Biology, National and Kapodistrian University of Athens, Athens, Greece
| | - George Tsiamis
- Department of Environmental Engineering, University of Patras, Agrinio, Greece
| | - Milton A Typas
- Department of Genetics and Biotechnology, Faculty of Biology, National and Kapodistrian University of Athens, Athens, Greece
| | - Katherine M Pappas
- Department of Genetics and Biotechnology, Faculty of Biology, National and Kapodistrian University of Athens, Athens, Greece
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20
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Chang TS, Chiang CM, Kao YH, Wu JY, Wu YW, Wang TY. A New Triterpenoid Glucoside from a Novel Acidic Glycosylation of Ganoderic Acid A via Recombinant Glycosyltransferase of Bacillus subtilis. Molecules 2019; 24:E3457. [PMID: 31554155 DOI: 10.3390/molecules24193457] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2019] [Revised: 09/22/2019] [Accepted: 09/23/2019] [Indexed: 01/08/2023] Open
Abstract
Ganoderic acid A (GAA) is a bioactive triterpenoid isolated from the medicinal fungus Ganoderma lucidum. Our previous study showed that the Bacillus subtilis ATCC (American type culture collection) 6633 strain could biotransform GAA into compound (1), GAA-15-O-β-glucoside, and compound (2). Even though we identified two glycosyltransferases (GT) to catalyze the synthesis of GAA-15-O-β-glucoside, the chemical structure of compound (2) and its corresponding enzyme remain elusive. In the present study, we identified BsGT110, a GT from the same B. subtilis strain, for the biotransformation of GAA into compound (2) through acidic glycosylation. BsGT110 showed an optimal glycosylation activity toward GAA at pH 6 but lost most of its activity at pH 8. Through a scaled-up production, compound (2) was successfully isolated using preparative high-performance liquid chromatography and identified to be a new triterpenoid glucoside (GAA-26-O-β-glucoside) by mass and nuclear magnetic resonance spectroscopy. The results of kinetic experiments showed that the turnover number (kcat) of BsGT110 toward GAA at pH 6 (kcat = 11.2 min−1) was 3-fold higher than that at pH 7 (kcat = 3.8 min−1), indicating that the glycosylation activity of BsGT110 toward GAA was more active at acidic pH 6. In short, we determined that BsGT110 is a unique GT that plays a role in the glycosylation of triterpenoid at the C-26 position under acidic conditions, but loses most of this activity under alkaline ones, suggesting that acidic solutions may enhance the catalytic activity of this and similar types of GTs toward triterpenoids.
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Kittl M, Helm K, Beyreis M, Mayr C, Gaisberger M, Winklmayr M, Ritter M, Jakab M. Acid- and Volume-Sensitive Chloride Currents in Microglial Cells. Int J Mol Sci 2019; 20:E3475. [PMID: 31311135 DOI: 10.3390/ijms20143475] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2019] [Revised: 07/11/2019] [Accepted: 07/12/2019] [Indexed: 01/27/2023] Open
Abstract
Many cell types express an acid-sensitive outwardly rectifying (ASOR) anion current of an unknown function. We characterized such a current in BV-2 microglial cells and then studied its interrelation with the volume-sensitive outwardly rectifying (VSOR) Cl− current and the effect of acidosis on cell volume regulation. We used patch clamp, the Coulter method, and the pH-sensitive dye BCECF to measure Cl− currents and cell membrane potentials, mean cell volume, and intracellular pH, respectively. The ASOR current activated at pH ≤ 5.0 and displayed an I− > Cl− > gluconate− permeability sequence. When compared to the VSOR current, it was similarly sensitive to DIDS, but less sensitive to DCPIB, and insensitive to tamoxifen. Under acidic conditions, the ASOR current was the dominating Cl− conductance, while the VSOR current was apparently inactivated. Acidification caused cell swelling under isotonic conditions and prevented the regulatory volume decrease under hypotonicity. We conclude that acidification, associated with activation of the ASOR- and inactivation of the VSOR current, massively impairs cell volume homeostasis. ASOR current activation could affect microglial function under acidotoxic conditions, since acidosis is a hallmark of pathophysiological events like inflammation, stroke or ischemia and migration and phagocytosis in microglial cells are closely related to cell volume regulation.
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Gallagher T, Phan J, Oliver A, Chase AB, England WE, Wandro S, Hendrickson C, Riedel SF, Whiteson K. Cystic Fibrosis-Associated Stenotrophomonas maltophilia Strain-Specific Adaptations and Responses to pH. J Bacteriol 2019; 201:e00478-18. [PMID: 30642989 DOI: 10.1128/JB.00478-18] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2018] [Accepted: 01/08/2019] [Indexed: 01/22/2023] Open
Abstract
Understanding bacterial responses to physiological conditions is an important priority for combating opportunistic infections. The majority of CF patients succumb to inflammation and necrosis in the airways, arising from chronic infection due to ineffective mucociliary clearance. Steep pH gradients characterize the CF airways but are not often incorporated in standard microbiology culture conditions. Stenotrophomonas maltophilia is a prevalent CF opportunistic pathogen also found in many disparate environments, yet this bacterium’s contribution to CF lung damage and its response to changing environmental factors remain largely understudied. Here, we show that pH impacts the physiology and antibiotic susceptibility of S. maltophilia, with implications for the development of relevant in vitro models and assessment of antibiotic sensitivity. The airway fluids of cystic fibrosis (CF) patients contain local pH gradients and are more acidic than those of healthy individuals. pH is a critical factor that is often overlooked in studies seeking to recapitulate the infection microenvironment. We sought to determine the impact of pH on the physiology of a ubiqituous yet understudied microbe, Stenotrophomonas maltophilia. Phylogenomics was first used to reconstruct evolutionary relationships between 74 strains of S. maltophilia (59 from CF patients). Neither the core genome (2,158 genes) nor the accessory genome (11,978 genes) distinguish the CF and non-CF isolates; however, strains from similar isolation sources grouped into the same subclades. We grew two human and six CF S. maltophilia isolates from different subclades at a range of pH values and observed impaired growth and altered antibiotic tolerances at pH 5. Transcriptomes revealed increased expression of both antibiotic resistance and DNA repair genes in acidic conditions. Although the gene expression profiles of S. maltophilia in lab cultures and CF sputum were distinct, we found that the same genes associated with low pH were also expressed during infection, and the higher pH cultures were more similar to sputum metatranscriptomes. Our findings suggest that S. maltophilia is not well adapted to acidity and may cope with low pH by expressing stress response genes and colonizing less acidic microenvironments. As a whole, our study underlines the impact of microenvironments on bacterial colonization and adaptation in CF infections. IMPORTANCE Understanding bacterial responses to physiological conditions is an important priority for combating opportunistic infections. The majority of CF patients succumb to inflammation and necrosis in the airways, arising from chronic infection due to ineffective mucociliary clearance. Steep pH gradients characterize the CF airways but are not often incorporated in standard microbiology culture conditions. Stenotrophomonas maltophilia is a prevalent CF opportunistic pathogen also found in many disparate environments, yet this bacterium’s contribution to CF lung damage and its response to changing environmental factors remain largely understudied. Here, we show that pH impacts the physiology and antibiotic susceptibility of S. maltophilia, with implications for the development of relevant in vitro models and assessment of antibiotic sensitivity.
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Take K, Fujiki H, Suyotha W, Hayashi J, Takagi K, Yano S, Wakayama M. Enzymatic and molecular characterization of an acidic and thermostable chitinase 1 from Streptomyces thermodiastaticus HF 3-3. J GEN APPL MICROBIOL 2018; 64:190-197. [PMID: 29709891 DOI: 10.2323/jgam.2017.12.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Chitinase 1 (Chi1) is an acidic and thermostable hydrolytic enzyme capable of the breakdown of chitin, a resilient biopolymer that is the primary building block of fungi cell walls and marine exoskeletons. In this study, Chi1 was purified from the bacterium Streptomyces thermodiastaticus HF 3-3, and its properties were carefully characterized. The molecular mass of Chi1 was estimated to be approximately 46 kDa and, through sequencing, its N-terminal amino acid sequence was identified as ADSGKVKL. Although the optimal operating temperature and pH for Chi1 were determined to be 65°C and pH 5.5, respectively, the purified enzyme was stable over wide pH (1.5-9) and temperature ranges. Moreover, Chi1 retained 87% of its activity in the presence of 15% NaCl. While Chi1 activity was inhibited by Ag+ and Mn2+, other chemicals tested had no significant effect on its enzymatic activity. The Km and Vmax values of Chi1 for the substrate colloidal chitin were 1.23 ± 0.7 mg/mL and 6.33 ± 1.0 U/mg, respectively. Thin-layer chromatography analysis of the enzymatic reaction end products mainly detected diacetylchitobiose. We also cloned the Chi1 gene and purified the recombinant protein; the properties of the recombinant enzyme were nearly identical to those of the native enzyme. Therefore, Chi1 purified from S. thermodiastaticus HF 3-3 is unique, as it is highly stable under broad range of pH values, temperatures, and chemical exposures. Combined, these properties make this enzyme attractive for use in the industrial bioconversion of chitin.
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Affiliation(s)
- Keitaro Take
- Department of Biotechnology, Faculty of Life Sciences, Ritsumeikan University
| | - Hidehisa Fujiki
- Department of Biotechnology, Faculty of Life Sciences, Ritsumeikan University
| | - Wasana Suyotha
- Biotechnology for Bioresource Utilization Laboratory, Department of Industrial Biotechnology, Faculty of Agro-industry, Prince of Songkla University
| | - Junji Hayashi
- Department of Biotechnology, Faculty of Life Sciences, Ritsumeikan University
| | - Kazuyoshi Takagi
- Department of Applied Chemistry, Faculty of Life Sciences, Ritsumeikan University
| | - Shigekazu Yano
- Department of Biochemical Engineering, Graduate School of Sciences and Engineering, Yamagata University
| | - Mamoru Wakayama
- Department of Biotechnology, Faculty of Life Sciences, Ritsumeikan University
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Hynek BM, Rogers KL, Antunovich M, Avard G, Alvarado GE. Lack of Microbial Diversity in an Extreme Mars Analog Setting: Poás Volcano, Costa Rica. Astrobiology 2018; 18:923-933. [PMID: 29688767 PMCID: PMC6067093 DOI: 10.1089/ast.2017.1719] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
The Poás volcano in Costa Rica has been studied as a Mars geochemical analog environment, since both the style of hydrothermal alteration present and the alteration mineralogy are consistent with Mars' relict hydrothermal systems. The site hosts an active volcano, with high-temperature fumaroles (up to 980°C) and an ultra-acidic lake. This lake, Laguna Caliente, is one of the most dynamic environments on Earth, with frequent phreatic eruptions, temperatures ranging from near-ambient to almost boiling, a pH range of -1 to 1.5, and a wide range of chemistries and redox potential. Martian acid-sulfate hydrothermal systems were likely similarly dynamic and equally challenging to life. The microbiology existing within Laguna Caliente was characterized for the first time, with sampling taking place in November, 2013. The diversity of the microbial community was surveyed via extraction of environmental DNA from fluid and sediment samples followed by Illumina sequencing of the 16S rRNA gene. The microbial diversity was limited to a single species of the bacterial genus Acidiphilium. This organism likely gets its energy from oxidation of reduced sulfur in the lake, including elemental sulfur. Given Mars' propensity for sulfur and acid-sulfate environments, this type of organism is of significant interest to the search for past or present life on the Red Planet. Key Words: Mars astrobiology-Acid-sulfate hydrothermal systems-Extremophiles-Acidic-High temperature-Acidiphilium bacteria. Astrobiology 18, 923-933.
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Affiliation(s)
- Brian M. Hynek
- Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, Colorado, USA
- Department of Geological Sciences, University of Colorado, Boulder, Colorado, USA
- Address correspondence to:Brian M. HynekLaboratory for Atmospheric and Space PhysicsUniversity of Colorado3665 Discovery Dr.Boulder, CO 80303
| | - Karyn L. Rogers
- Earth and Environmental Sciences, Rensselaer Polytechnic Institute, Troy, New York, USA
| | - Monique Antunovich
- Department of Geological Sciences, University of Colorado, Boulder, Colorado, USA
| | - Geoffroy Avard
- OVSICORI, National University of Costa Rica, Heredia, Costa Rica
| | - Guillermo E. Alvarado
- Centro de Investigaciones Geológicas, Red Sismológica Nacional, Universidad de Costa Rica, Costa Rica
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Affiliation(s)
- Anusha Singh
- a Division of Pharmaceutics and Pharmaceutical Chemistry , College of Pharmacy, The Ohio State University , Columbus , OH 43210 , USA
| | - Rajgopal Govindarajan
- a Division of Pharmaceutics and Pharmaceutical Chemistry , College of Pharmacy, The Ohio State University , Columbus , OH 43210 , USA.,b Translational Therapeutics, Ohio State University Comprehensive Cancer Center, The Ohio State University , Columbus , OH 43210 , USA
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Tung CH, Qi J, Hu L, Han MS, Kim Y. A Quick Responsive Fluorogenic pH Probe for Ovarian Tumor Imaging. Theranostics 2015; 5:1166-74. [PMID: 26284146 PMCID: PMC4533099 DOI: 10.7150/thno.12813] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2015] [Accepted: 07/09/2015] [Indexed: 12/25/2022] Open
Abstract
A novel cell-permeable compound, CypH-1, that is non-fluorescent at neutral pH, but fluoresces under mildly acidic conditions with a near infrared maximum emission wavelength was designed for the detection of tumors in the clinical setting. The potential of CypH-1 in ovarian cancer imaging was demonstrated using a murine model. The intraperitoneally administered CypH-1 results in a robust fluorescence signal of discrete neoplastic lesions with millimeter range resolution within few hours. Moreover, fluorescence signal is strikingly enhanced at peripheral regions of tumors at the microscopic level suggesting a sharp physiological difference at the tumor/normal tissue interface. This robust acid-activated imaging agent is expected to have significant impact in broad surgical and diagnostic applications.
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