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Blake MJ, Page EF, Smith ME, Calhoun TR. Miltefosine impacts small molecule transport in Gram-positive bacteria. RSC Chem Biol 2024; 5:981-988. [PMID: 39363965 PMCID: PMC11446237 DOI: 10.1039/d4cb00106k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2024] [Accepted: 07/04/2024] [Indexed: 10/05/2024] Open
Abstract
Miltefosine (MLT) is an alkylphosphocholine with clinical success as an anticancer and antiparasitic drug. Although the mechanism of action of MLT is highly debated, the interaction of MLT with the membrane, specifically lipid rafts of eukaryotes, is well-documented. Recent reports suggest MLT impacts the functional membrane microdomains in bacteria - regions of the membrane structurally and functionally similar to lipid rafts. There have been conflicting reports, however, as to whether MLT impacts the overall fluidity of cellular plasma membranes. Here, we apply steady-state fluorescence techniques, generalized polarization of laurdan and anisotropy of diphenylhexatriene, to discern how MLT impacts the global ordering and lipid packing of Staphylococcus aureus membranes. Additionally, we investigate how the transport of a range of small molecules is impacted by MLT for S. aureus and Bacillus subtilis by employing time-resolved second harmonic scattering. Overall, we observe MLT does not have an influence on the overall ordering and packing of S. aureus membranes. Additionally, we show that the transport of small molecules across the membrane can be significantly altered by MLT - although this is not the case for all molecules studied. The results presented here illustrate the potential use of MLT as an adjuvant to assist in the delivery of drug molecules in bacteria.
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2
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Kumar D, Gayen A, Chandra M. Growth Phase Contribution in Dictating Drug Transport and Subcellular Accumulation inside Escherichia coli. ACS Infect Dis 2024; 10:3233-3244. [PMID: 39178142 DOI: 10.1021/acsinfecdis.4c00252] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/25/2024]
Abstract
Depending upon nutrient availability, bacteria transit to multiple growth phases. The transition from the active to nongrowing phase results in reduced drug efficacy and, in some cases, even multidrug resistance. However, due to multiple alterations in the cell envelope, probing the drug permeation kinetics during growth phases becomes perplexing, especially across the Gram-negative bacteria's complex dual membrane envelope. To advance the understanding of drug permeation during the life cycle of Gram-negative bacteria, we sought to address two underlying objectives: (a) how changes are occurring inside the bacterial envelope during growth and (b) how the drug permeation and accumulation vary across both the membranes and in subcellular compartments during growth. Both objectives are met with the help of nonlinear optical technique second-harmonic generation spectroscopy (SHG). Specifically, using SHG, we probed the transport kinetics and accumulation of a quaternary ammonium compound (QAC), malachite green, inside Escherichia coli in various growth phases. Further insight about another QAC molecule, propidium iodide, is accomplished using fluorescence microscopy. Results indicate that actively growing cells have faster drug transport and higher cytoplasmic accumulation than slow- or nongrowing cells. In this regard, the rpoS gene plays a crucial role in limiting drug transport across the saturation phase cultures. Moreover, within a particular growth phase, membrane permeability undergoes gradual changes much before the subsequent growth phase commences. These outcomes signify the importance of reporting the growth phase and rate in drug efficacy studies.
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Affiliation(s)
- Deepak Kumar
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur, Uttar Pradesh 208016, India
| | - Anindita Gayen
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur, Uttar Pradesh 208016, India
| | - Manabendra Chandra
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur, Uttar Pradesh 208016, India
- Center of Excellence: Tropical and Infectious Diseases, Gangwal School of Medical Sciences and Technology, Indian Institute of Technology Kanpur, Kanpur, Uttar Pradesh 208016, India
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3
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Kwapiszewska K. Physicochemical Perspective of Biological Heterogeneity. ACS PHYSICAL CHEMISTRY AU 2024; 4:314-321. [PMID: 39069985 PMCID: PMC11274282 DOI: 10.1021/acsphyschemau.3c00079] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/29/2023] [Revised: 03/25/2024] [Accepted: 03/25/2024] [Indexed: 07/30/2024]
Abstract
The vast majority of chemical processes that govern our lives occur within living cells. At the core of every life process, such as gene expression or metabolism, are chemical reactions that follow the fundamental laws of chemical kinetics and thermodynamics. Understanding these reactions and the factors that govern them is particularly important for the life sciences. The physicochemical environment inside cells, which can vary between cells and organisms, significantly impacts various biochemical reactions and increases the extent of population heterogeneity. This paper discusses using physical chemistry approaches for biological studies, including methods for studying reactions inside cells and monitoring their conditions. The potential for development in this field and possible new research areas are highlighted. By applying physical chemistry methodology to biochemistry in vivo, we may gain new insights into biology, potentially leading to new ways of controlling biochemical reactions.
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Affiliation(s)
- Karina Kwapiszewska
- Institute of Physical Chemistry, Polish
Academy of Sciences, Kasprzaka 44/52, Warsaw 01-224, Poland
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4
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Chen S, Liu Z, Li B, Hou Y, Peng Y, Li J, Yuan Q, Gan W. Probing the structural evolution on the surface of cardiolipin vesicles with an amphiphilic second harmonic generation and fluorescence probe. J Chem Phys 2024; 161:014705. [PMID: 38949588 DOI: 10.1063/5.0211845] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2024] [Accepted: 06/15/2024] [Indexed: 07/02/2024] Open
Abstract
Investigating the influence of the ambient chemical environment on molecular behaviors in liposomes is crucial for understanding and manipulating cellular vitality as well as the capabilities of lipid drug carriers in various environments. Here, we designed and synthesized a second harmonic generation (SHG) and fluorescence probe molecule called Pyr-Py+-N+ (PPN), which possesses membrane-targeting capability. We employed PPN to investigate the response of lipid vesicles composed of cardiolipin to the presence of exogenous salt. The kinetic behaviors, including the adsorption and embedding of PPN on the surface of small unilamellar vesicles (SUVs) composed of cardiolipin, were analyzed. The response of the SUVs to the addition of NaCl was also monitored. A rapid decrease in vesicle size can be evidenced through the rapid drop in SHG emission originating from PPN located on the vesicle surface.
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Affiliation(s)
- Shujiao Chen
- Shenzhen Key Laboratory of Flexible Printed Electronics Technology, School of Science, Harbin Institute of Technology (Shenzhen), University Town, Shenzhen 518055, Guangdong, China and School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin 150001, Heilongjiang, China
| | - Zhongcheng Liu
- Department of Chemistry, Tsinghua University, Beijing 100084, China
| | - Bifei Li
- Shenzhen Key Laboratory of Flexible Printed Electronics Technology, School of Science, Harbin Institute of Technology (Shenzhen), University Town, Shenzhen 518055, Guangdong, China and School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin 150001, Heilongjiang, China
| | - Yi Hou
- Shenzhen Key Laboratory of Flexible Printed Electronics Technology, School of Science, Harbin Institute of Technology (Shenzhen), University Town, Shenzhen 518055, Guangdong, China and School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin 150001, Heilongjiang, China
| | - Yingying Peng
- Shenzhen Key Laboratory of Flexible Printed Electronics Technology, School of Science, Harbin Institute of Technology (Shenzhen), University Town, Shenzhen 518055, Guangdong, China and School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin 150001, Heilongjiang, China
| | - Jianhui Li
- Shenzhen Key Laboratory of Flexible Printed Electronics Technology, School of Science, Harbin Institute of Technology (Shenzhen), University Town, Shenzhen 518055, Guangdong, China and School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin 150001, Heilongjiang, China
| | - Qunhui Yuan
- Shenzhen Key Laboratory of Flexible Printed Electronics Technology, School of Materials Science and Engineering, Harbin Institute of Technology (Shenzhen), University Town, Shenzhen 518055, Guangdong, China
| | - Wei Gan
- Shenzhen Key Laboratory of Flexible Printed Electronics Technology, School of Science, Harbin Institute of Technology (Shenzhen), University Town, Shenzhen 518055, Guangdong, China and School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin 150001, Heilongjiang, China
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5
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Kumar D, Gayen A, Chandra M. Membrane Permeability Dominates over Electrostatic Interactions in Dictating Drug Transport in Osmotically Shocked Escherichia coli. J Phys Chem B 2024; 128:4911-4921. [PMID: 38736363 DOI: 10.1021/acs.jpcb.3c08426] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/14/2024]
Abstract
To combat surging multidrug-resistant Gram-negative bacterial infections, better strategies to improve the efficacy of existing drugs are critical. Because the dual membrane cell envelope is the first line of defense for these bacteria, it is crucial to understand the permeation properties of the drugs through it. Our recent study shows that isosmotic conditions prevent drug permeation inside Gram-negative bacteria, Escherichia coli, while hypoosmotic stress enhances the process. Here, we unravel the reason behind such differential drug penetration. Specifically, we dissect the roles of electrostatic screening and low membrane permeability in the penetration failure of drugs under osmotically balanced conditions. We compare the transport of a quaternary ammonium compound malachite green in the presence of an electrolyte (NaCl) and a wide variety of commonly used organic osmolytes, e.g., sucrose, proline, glycerol, sorbitol, and urea. These osmolytes of different membrane permeability (i.e., nonpermeable sucrose and NaCl, freely permeable urea and glycerol, and partially permeable proline and sorbitol) clarify the role of osmotic stress in cell envelope permeability. The results showcase that under balanced osmotic conditions, drug molecules fail to penetrate inside E. coli cells because of low membrane permeabilities and not because of electrostatic screening imposed by the osmolytes. Contribution of the electrostatic interactions, however, cannot be completely overruled as at osmotically imbalanced conditions, drug transport across the bacterial subcellular compartments is found to be dependent on the osmolytes used.
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Affiliation(s)
- Deepak Kumar
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208016, Uttar Pradesh, India
| | - Anindita Gayen
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208016, Uttar Pradesh, India
| | - Manabendra Chandra
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208016, Uttar Pradesh, India
- Center of Excellence: Tropical and Infectious Diseases, Gangwal School of Medical Sciences and Technology, Indian Institute of Technology Kanpur, Kanpur 208016, Uttar Pradesh, India
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6
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Blake MJ, Castillo HB, Curtis AE, Calhoun TR. Facilitating flip-flop: Structural tuning of molecule-membrane interactions in living bacteria. Biophys J 2023; 122:1735-1747. [PMID: 37041744 PMCID: PMC10209030 DOI: 10.1016/j.bpj.2023.04.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Revised: 03/17/2023] [Accepted: 04/04/2023] [Indexed: 04/13/2023] Open
Abstract
The first barrier that a small molecule must overcome before trespassing into a living cell is the lipid bilayer surrounding the intracellular content. It is imperative, therefore, to understand how the structure of a small molecule influences its fate in this region. Through the use of second harmonic generation, we show how the differing degrees of ionic headgroups, conjugated system, and branched hydrocarbon tail disparities of a series of four styryl dye molecules influence the propensity to "flip-flop" or to be further organized in the outer leaflet by the membrane. We show here that initial adsorption experiments match previous studies on model systems; however, more complex dynamics are observed over time. Aside from probe molecule structure, these dynamics also vary between cell species and can deviate from trends reported based on model membranes. Specifically, we show here that the membrane composition is an important factor to consider for headgroup-mediated small-molecule dynamics. Overall, the findings presented here on how structural variability of small molecules impacts their initial adsorption and eventual destinations within membranes in the context of living cells could have practical applications in antibiotic and drug adjuvant design.
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Affiliation(s)
- Marea J Blake
- Department of Chemistry, University of Tennessee, Knoxville, Tennessee
| | - Hannah B Castillo
- Department of Chemistry, University of Tennessee, Knoxville, Tennessee
| | - Anna E Curtis
- Department of Chemistry, University of Tennessee, Knoxville, Tennessee
| | - Tessa R Calhoun
- Department of Chemistry, University of Tennessee, Knoxville, Tennessee.
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Page EF, Blake MJ, Foley GA, Calhoun TR. Monitoring membranes: The exploration of biological bilayers with second harmonic generation. CHEMICAL PHYSICS REVIEWS 2022; 3:041307. [PMID: 36536669 PMCID: PMC9756348 DOI: 10.1063/5.0120888] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/15/2022] [Accepted: 11/03/2022] [Indexed: 12/23/2022]
Abstract
Nature's seemingly controlled chaos in heterogeneous two-dimensional cell membranes stands in stark contrast to the precise, often homogeneous, environment in an experimentalist's flask or carefully designed material system. Yet cell membranes can play a direct role, or serve as inspiration, in all fields of biology, chemistry, physics, and engineering. Our understanding of these ubiquitous structures continues to evolve despite over a century of study largely driven by the application of new technologies. Here, we review the insight afforded by second harmonic generation (SHG), a nonlinear optical technique. From potential measurements to adsorption and diffusion on both model and living systems, SHG complements existing techniques while presenting a large exploratory space for new discoveries.
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Affiliation(s)
- Eleanor F. Page
- Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, USA
| | - Marea J. Blake
- Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, USA
| | - Grant A. Foley
- Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, USA
| | - Tessa R. Calhoun
- Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, USA
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8
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Hamal P, Subasinghege Don V, Nguyenhuu H, Ranasinghe JC, Nauman JA, McCarley RL, Kumar R, Haber LH. Influence of Temperature on Molecular Adsorption and Transport at Liposome Surfaces Studied by Molecular Dynamics Simulations and Second Harmonic Generation Spectroscopy. J Phys Chem B 2021; 125:10506-10513. [PMID: 34495664 PMCID: PMC8474114 DOI: 10.1021/acs.jpcb.1c04263] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
A fundamental understanding of the kinetics and thermodynamics of chemical interactions at the phospholipid bilayer interface is crucial for developing potential drug-delivery applications. Here we use molecular dynamics (MD) simulations and surface-sensitive second harmonic generation (SHG) spectroscopy to study the molecular adsorption and transport of a small organic cation, malachite green (MG), at the surface of 1,2-dioleoyl-sn-glycero-3-phospho-(1'-rac-glycerol) (DOPG) liposomes in water at different temperatures. The temperature-dependent adsorption isotherms, obtained by SHG measurements, provide information on adsorbate concentration, free energy of adsorption, and associated changes in enthalpy and entropy, showing that the adsorption process is exothermic, resulting in increased overall entropy. Additionally, the molecular transport kinetics are found to be more rapid under higher temperatures. Corresponding MD simulations are used to calculate the free energy profiles of the adsorption and the molecular orientation distributions of MG at different temperatures, showing excellent agreement with the experimental results.
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Affiliation(s)
- Prakash Hamal
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803-1804, United States
| | - Visal Subasinghege Don
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803-1804, United States
| | - Huy Nguyenhuu
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803-1804, United States
| | - Jeewan C Ranasinghe
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803-1804, United States
| | - Julia A Nauman
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803-1804, United States
| | - Robin L McCarley
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803-1804, United States
| | - Revati Kumar
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803-1804, United States
| | - Louis H Haber
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803-1804, United States
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9
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Bernhard C, van Zadel MJ, Bunn A, Bonn M, Gonella G. In Situ Label-Free Study of Protein Adsorption on Nanoparticles. J Phys Chem B 2021; 125:9019-9026. [PMID: 34323495 PMCID: PMC8389981 DOI: 10.1021/acs.jpcb.1c04775] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Revised: 07/11/2021] [Indexed: 12/02/2022]
Abstract
Improving the design of nanoparticles for use as drug carriers or biosensors requires a better understanding of the protein-nanoparticle interaction. Here, we present a new tool to investigate this interaction in situ and without additional labeling of the proteins and/or nanoparticles. By combining nonresonant second-harmonic light scattering with a modified Langmuir model, we show that it is possible to gain insight into the adsorption behavior of blood proteins, namely fibrinogen, human serum albumin, and transferrin, onto negatively charged polystyrene nanoparticles. The modified Langmuir model gives us access to the maximum amount of adsorbed protein, the apparent binding constant, and Gibbs free energy. Furthermore, we employ the method to investigate the influence of the nanoparticle size on the adsorption of human serum albumin and find that the amount of adsorbed protein increases more than the surface area per nanoparticle for larger diameters.
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Affiliation(s)
- Christoph Bernhard
- Max Planck Institute for
Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
| | - Marc-Jan van Zadel
- Max Planck Institute for
Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
| | - Alexander Bunn
- Max Planck Institute for
Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
| | - Mischa Bonn
- Max Planck Institute for
Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
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10
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Observing the structural variations on binary complex vesicle surfaces and the influence on molecular transportation. Chem Phys 2021. [DOI: 10.1016/j.chemphys.2021.111250] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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11
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Sharifian Gh M. Recent Experimental Developments in Studying Passive Membrane Transport of Drug Molecules. Mol Pharm 2021; 18:2122-2141. [PMID: 33914545 DOI: 10.1021/acs.molpharmaceut.1c00009] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The ability to measure the passive membrane permeation of drug-like molecules is of fundamental biological and pharmaceutical importance. Of significance, passive diffusion across the cellular membranes plays an effective role in the delivery of many pharmaceutical agents to intracellular targets. Hence, approaches for quantitative measurement of membrane permeability have been the topics of research for decades, resulting in sophisticated biomimetic systems coupled with advanced techniques. In this review, recent developments in experimental approaches along with theoretical models for quantitative and real-time analysis of membrane transport of drug-like molecules through mimetic and living cell membranes are discussed. The focus is on time-resolved fluorescence-based, surface plasmon resonance, and second-harmonic light scattering approaches. The current understanding of how properties of the membrane and permeant affect the permeation process is discussed.
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Affiliation(s)
- Mohammad Sharifian Gh
- Department of Cell Biology, University of Virginia, Charlottesville, Virginia 22908, United States
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12
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Wilhelm MJ, Sharifian Gh M, Wu T, Li Y, Chang CM, Ma J, Dai HL. Determination of bacterial surface charge density via saturation of adsorbed ions. Biophys J 2021; 120:2461-2470. [PMID: 33932437 DOI: 10.1016/j.bpj.2021.04.018] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Revised: 04/12/2021] [Accepted: 04/14/2021] [Indexed: 01/17/2023] Open
Abstract
Bacterial surface charge is a critical characteristic of the cell's interfacial physiology that influences how the cell interacts with the local environment. A direct, sensitive, and accurate experimental technique capable of quantifying bacterial surface charge is needed to better understand molecular adaptations in interfacial physiology in response to environmental changes. We introduce here the method of second-harmonic light scattering (SHS), which is capable of detecting the number of molecular ions adsorbed as counter charges on the exterior bacterial surface, thereby providing a measure of the surface charge. In this first demonstration, we detect the small molecular cation, malachite green, electrostatically adsorbed on the surface of representative strains of Gram-positive and Gram-negative bacteria. Surprisingly, the SHS-deduced molecular transport rates through the different cellular ultrastructures are revealed to be nearly identical. However, the adsorption saturation densities on the exterior surfaces of the two bacteria were shown to be characteristically distinct. The negative charge density of the lipopolysaccharide coated outer surface of Gram-negative Escherichia coli (6.6 ± 1.3 nm-2) was deduced to be seven times larger than that of the protein surface layer of Gram-positive Lactobacillus rhamnosus (1.0 ± 0.2 nm-2). The feasibility of SHS-deduced bacterial surface charge density for Gram-type differentiation is presented.
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Affiliation(s)
- Michael J Wilhelm
- Department of Chemistry, Temple University, Philadelphia, Pennsylvania.
| | | | - Tong Wu
- Department of Chemistry, Temple University, Philadelphia, Pennsylvania
| | - Yujie Li
- Department of Chemistry, Temple University, Philadelphia, Pennsylvania
| | - Chia-Mei Chang
- Department of Chemistry, Temple University, Philadelphia, Pennsylvania
| | - Jianqiang Ma
- Department of Chemistry, Temple University, Philadelphia, Pennsylvania
| | - Hai-Lung Dai
- Department of Chemistry, Temple University, Philadelphia, Pennsylvania
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