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Fortenberry A, Mohammad SA, Werfel TA, Smith AE. Comparative Investigation of the Hydrolysis of Charge-Shifting Polymers Derived from an Azlactone-Based Polymer. Macromol Rapid Commun 2022; 43:e2200420. [PMID: 35820157 PMCID: PMC9780167 DOI: 10.1002/marc.202200420] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2022] [Revised: 06/28/2022] [Indexed: 12/25/2022]
Abstract
Poly 2-vinyl-4,4-dimethylazlactone (PVDMA) has received much attention as a "reactive platform" to prepare charge-shifting polycations via post-polymerization modification with tertiary amines that possess primary amine or hydroxyl reactive handles. Upon hydrolysis of the resulting amide or ester linkages, the polymers can undergo a gradual transition in net charge from cationic to anionic. Herein, a systematic investigation of the hydrolysis rate of PVDMA-derived charge-shifting polymers is described. PVDMA is modified with tertiary amines bearing either primary amine, hydroxyl, or thiol reactive handles. The resulting polymers possess tertiary amine side chains connected to the backbone via amide, ester, or thioester linkages. The hydrolysis rates of each PVDMA derivative are monitored at 25 and 50 °C at pH values of 5.5, 7.5, and 8.5, respectively. While the hydrolysis rate of the amide-functionalized PVDMA is negligible over the period investigated, the hydrolysis rates of the ester- and thioester-functionalized PVDMA increase with increasing temperature and pH. Interestingly, the hydrolysis rate of the thioester-functionalized PVDMA appears to be more rapid than the ester-functionalized PVDMA at all pH values and temperatures investigated. It is believed that these results can be utilized to inform the future preparation of PVDMA-based charge-shifting polymers for biomedical applications.
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Affiliation(s)
- Alex Fortenberry
- Department of Chemical Engineering, University of Mississippi, MS, USA
| | - Sk Arif Mohammad
- Department of Biomedical Engineering, University of Mississippi, MS, USA
| | - Thomas A. Werfel
- Department of Chemical Engineering, University of Mississippi, MS, USA
- Department of Biomedical Engineering, University of Mississippi, MS, USA
- Department of BioMolecular Sciences, University of Mississippi, University, MS, USA
- Cancer Center and Research Institute, University of Mississippi Medical Center, Jackson, MS, USA
| | - Adam E. Smith
- Department of Chemical Engineering, University of Mississippi, MS, USA
- Department of Biomedical Engineering, University of Mississippi, MS, USA
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2
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Masigol M, Radaha EL, Kannan AD, Salberg AG, Fattahi N, Parameswaran P, Hansen RR. Polymer Surface Dissection for Correlated Microscopic and Compositional Analysis of Bacterial Aggregates during Membrane Biofouling. ACS APPLIED BIO MATERIALS 2022; 5:134-145. [PMID: 35014824 DOI: 10.1021/acsabm.1c00971] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Multispecies biofilms are a common limitation in membrane bioreactors, causing membrane clogging, degradation, and failure. There is a poor understanding of biological fouling mechanisms in these systems due to the limited number of experimental techniques useful for probing microbial interactions at the membrane interface. Here, we develop a new experimental method, termed polymer surface dissection (PSD), to investigate multispecies assembly processes over membrane surfaces. The PSD method uses photodegradable polyethylene glycol hydrogels functionalized with bioaffinity ligands to bind and detach microscale, microbial aggregates from the membrane for microscopic observation. Subsequent exposure of the hydrogel to high resolution, patterned UV light allows for controlled release of any selected aggregate of desired size at high purity for DNA extraction. Follow-up 16S community analysis reveals aggregate composition, correlating microscopic images with the bacterial community structure. The optimized approach can isolate aggregates with microscale spatial precision and yields genomic DNA at sufficient quantity and quality for sequencing from aggregates with areas as low as 2000 μm2, without the need of culturing for sample enrichment. To demonstrate the value of the approach, PSD was used to reveal the composition of microscale aggregates of different sizes during early-stage biofouling of aerobic wastewater communities over PVDF membranes. Larger aggregates exhibited lower diversity of bacterial communities, and a shift in the community structure was found as aggregate size increased to areas between 25,000 and 45,000 μm2, below which aggregates were more enriched in Bacteroidetes and above which aggregates were more enriched with Proteobacteria. The findings demonstrate that community succession can be observed within microscale aggregates and that the PSD method is useful for identification and characterization of early colonizing bacteria that drive biofouling on membrane surfaces.
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Affiliation(s)
- Mohammadali Masigol
- Tim Taylor Department of Chemical Engineering, Kansas State University, Manhattan, Kansas 66506, United States
| | - Esther L Radaha
- Tim Taylor Department of Chemical Engineering, Kansas State University, Manhattan, Kansas 66506, United States
| | - Arvind D Kannan
- Department of Civil Engineering, Kansas State University, Manhattan, Kansas 66506, United States
| | - Abigail G Salberg
- Tim Taylor Department of Chemical Engineering, Kansas State University, Manhattan, Kansas 66506, United States
| | - Niloufar Fattahi
- Tim Taylor Department of Chemical Engineering, Kansas State University, Manhattan, Kansas 66506, United States
| | - Prathap Parameswaran
- Department of Civil Engineering, Kansas State University, Manhattan, Kansas 66506, United States
| | - Ryan R Hansen
- Tim Taylor Department of Chemical Engineering, Kansas State University, Manhattan, Kansas 66506, United States
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3
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Hu B, Carrillo JM, Collins L, Silmore KS, Keum J, Bonnesen PV, Wang Y, Retterer S, Kumar R, Lokitz BS. Modular Approach for the Synthesis of Bottlebrush Diblock Copolymers from Poly(Glycidyl Methacrylate)-block-Poly(Vinyldimethylazlactone) Backbones. Macromolecules 2022. [DOI: 10.1021/acs.macromol.1c01849] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Bin Hu
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Jan-Michael Carrillo
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Liam Collins
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Kevin S. Silmore
- Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Jong Keum
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Peter V. Bonnesen
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Yangyang Wang
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Scott Retterer
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Rajeev Kumar
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Bradley S. Lokitz
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
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4
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Masigol M, Fattahi N, Barua N, Lokitz BS, Retterer ST, Platt TG, Hansen RR. Identification of Critical Surface Parameters Driving Lectin-Mediated Capture of Bacteria from Solution. Biomacromolecules 2019; 20:2852-2863. [PMID: 31150217 DOI: 10.1021/acs.biomac.9b00609] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Lectin-functional interfaces are useful for isolation of bacteria from solution because they are low-cost and allow nondestructive, reversible capture. This study provides a systematic investigation of physical and chemical surface parameters that influence bacteria capture over lectin-functionalized polymer interfaces and then applies these findings to construct surfaces with significantly enhanced bacteria capture. The designer block copolymer poly(glycidyl methacrylate)- block-poly(vinyldimethyl azlactone) was used as a lectin attachment layer, and lectin coupling into the polymer film through azlactone-lectin coupling reactions was first characterized. Here, experimental parameters including polymer areal chain density, lectin molecular weight, and lectin coupling buffer were systematically varied to identify parameters driving highest azlactone conversions and corresponding lectin surface densities. To introduce physical nanostructures into the attachment layer, nanopillar arrays (NPAs) of varied heights (300 and 2100 nm) were then used to provide an underlying surface template for the functional polymer layer. Capture of Escherichia coli on lectin-polymer surfaces coated over both flat and NPA surfaces was then investigated. For flat polymer interfaces, bacteria were detected on the surface after incubation at a solution concentration of 103 cfu/mL, and a corresponding detection limit of 1.7 × 103 cfu/mL was quantified. This detection limit was 1 order of magnitude lower than control lectin surfaces functionalized with standard, carbodiimide coupling chemistry. NPA surfaces containing 300 nm tall pillars further improved the detection limit to 2.1 × 102 cfu/mL, but also reduced the viability of captured cells. Finally, to investigate the impact of cell surface parameters on capture, we used Agrobacterium tumefaciens cells genetically modified to allow manipulation of exopolysaccharide adhesin production levels. Statistical analysis of surface capture levels revealed that lectin surface density was the primary factor driving capture, as opposed to exopolysaccharide adhesin expression. These findings emphasize the critical importance of the synthetic interface and the development of surfaces that combine high lectin densities with tailored physical features to drive high levels of capture. These insights will aid in design of biofunctional interfaces with physicochemical surface properties favorable for capture and isolation of bacteria cells from solutions.
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5
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Sequential binary protein patterning on surface domains of thermo-responsive polymer blends cast by horizontal-dipping. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2019; 99:1477-1484. [DOI: 10.1016/j.msec.2019.02.087] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2018] [Revised: 02/12/2019] [Accepted: 02/21/2019] [Indexed: 12/31/2022]
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6
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Barreca D, Neri G, Scala A, Fazio E, Gentile D, Rescifina A, Piperno A. Covalently immobilized catalase on functionalized graphene: effect on the activity, immobilization efficiency, and tetramer stability. Biomater Sci 2019; 6:3231-3240. [PMID: 30379150 DOI: 10.1039/c8bm00850g] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Herein we describe, for the first time, the covalent immobilization of catalase (CAT) on functionalized graphene surfaces (G) by exploiting the azalactone chemistry for the post-functionalization of graphene-based materials. The structure, morphology and chemical composition of catalase immobilized on graphene (CAT-G) have been investigated by Fourier-transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM/EDX). The biological responses such as catalytic activity, cellular uptake, internalization pathway, and the ability to protect lymphocytes from oxidative stress induced by H2O2 together with the unforeseen ability to increase the lifetime of the free catalase in solution have been deeply investigated. From our studies, it is evident that the behavior of CAT covalently linked to modified graphene depends on the CAT/G ratio that affects the secondary structure and the tetramer stability of CAT. In order to support the experimental results, we have also investigated the behaviors of two appropriately designed model systems, named CAT-surfer and CAT-skier, by molecular dynamics calculations. These in silico results parallel the experimental results proving our hypothesis that the CAT-surfer maintains the conformational flexibility needed for a biological response, whereas CAT-skier favors the dissociation of the tetramer subunits, involving the inactivation of the enzyme.
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Affiliation(s)
- Davide Barreca
- Department of Chemical, Biological, Pharmaceutical and Environmental Sciences, University of Messina, Viale F. Stagno D'Alcontres 31, I-98166, Italy.
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7
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Masigol M, Barua N, Lokitz BS, Hansen RR. Fabricating Reactive Surfaces with Brush-like and Crosslinked Films of Azlactone-Functionalized Block Co-Polymers. J Vis Exp 2018. [PMID: 30010667 DOI: 10.3791/57562] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
In this paper, fabrication methods that generate novel surfaces using the azlactone-based block co-polymer, poly (glycidyl methacrylate)-block-poly (vinyl dimethyl azlactone) (PGMA-b-PVDMA), are presented. Due to the high reactivity of azlactone groups towards amine, thiol, and hydroxyl groups, PGMA-b-PVDMA surfaces can be modified with secondary molecules to create chemically or biologically functionalized interfaces for a variety of applications. Previous reports of patterned PGMA-b-PVDMA interfaces have used traditional top-down patterning techniques that generate non-uniform films and poorly controlled background chemistries. Here, we describe customized patterning techniques that enable precise deposition of highly uniform PGMA-b-PVDMA films in backgrounds that are chemically inert or that have biomolecule-repellent properties. Importantly, these methods are designed to deposit PGMA-b-PVDMA films in a manner that completely preserves azlactone functionality through each processing step. Patterned films show well-controlled thicknesses that correspond to polymer brushes (~90 nm) or to highly crosslinked structures (~1-10 μm). Brush patterns are generated using either the parylene lift-off or interface directed assembly methods described and are useful for precise modulation of overall chemical surface reactivity by adjusting either the PGMA-b-PVDMA pattern density or the length of the VDMA block. In contrast, the thick, crosslinked PGMA-b-PVDMA patterns are obtained using a customized micro-contact printing technique and offer the benefit of higher loading or capture of secondary material due to higher surface area to volume ratios. Detailed experimental steps, critical film characterizations, and trouble-shooting guides for each fabrication method are discussed.
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Affiliation(s)
| | - Niloy Barua
- Chemical Engineering Department, Kansas State University
| | - Bradley S Lokitz
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory
| | - Ryan R Hansen
- Chemical Engineering Department, Kansas State University;
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8
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Retterer ST, Morrell-Falvey JL, Doktycz MJ. Nano-Enabled Approaches to Chemical Imaging in Biosystems. ANNUAL REVIEW OF ANALYTICAL CHEMISTRY (PALO ALTO, CALIF.) 2018; 11:351-373. [PMID: 29490189 DOI: 10.1146/annurev-anchem-061417-125635] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Understanding and predicting how biosystems function require knowledge about the dynamic physicochemical environments with which they interact and alter by their presence. Yet, identifying specific components, tracking the dynamics of the system, and monitoring local environmental conditions without disrupting biosystem function present significant challenges for analytical measurements. Nanomaterials, by their very size and nature, can act as probes and interfaces to biosystems and offer solutions to some of these challenges. At the nanoscale, material properties emerge that can be exploited for localizing biomolecules and making chemical measurements at cellular and subcellular scales. Here, we review advances in chemical imaging enabled by nanoscale structures, in the use of nanoparticles as chemical and environmental probes, and in the development of micro- and nanoscale fluidic devices to define and manipulate local environments and facilitate chemical measurements of complex biosystems. Integration of these nano-enabled methods will lead to an unprecedented understanding of biosystem function.
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Affiliation(s)
- Scott T Retterer
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA;
- Center for Nanophase Materials Science, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | | | - Mitchel J Doktycz
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA;
- Center for Nanophase Materials Science, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
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9
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Kim JJ, Reátegui E, Hopke A, Jalali F, Roushan M, Doyle PS, Irimia D. Large-scale patterning of living colloids for dynamic studies of neutrophil-microbe interactions. LAB ON A CHIP 2018; 18:1514-1520. [PMID: 29770423 PMCID: PMC5995581 DOI: 10.1039/c8lc00228b] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Neutrophils are the first white blood cells to respond to microbes and to limit their invasion of the body. However, the growth of the microbes into colonies often challenges the neutrophils ability to contain them. To study the interactions between neutrophils and microbial colonies, we designed an assay for arranging microbes in clusters of controlled size (i.e. living colloids). The patterned microbes in the living colloid are mechanically trapped inside the wells and fully accessible to neutrophils. Using the assay, we studied the interactions between human neutrophils and Candida albicans and Staphylococcus aureus, two common human pathogens. We also probed the susceptibility of C. albicans colloids to caspofungin, a common antifungal drug.
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Affiliation(s)
- Jae Jung Kim
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
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10
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Wang X, Davis JL, Aden BM, Lokitz BS, Kilbey SM. Versatile Synthesis of Amine-Reactive Microgels by Self-Assembly of Azlactone-Containing Block Copolymers. Macromolecules 2018. [DOI: 10.1021/acs.macromol.8b00405] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Xu Wang
- National Engineering Research Center for Colloidal Materials, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, P. R. China
| | | | | | - Bradley S. Lokitz
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, One Bethel Valley Road, Oak Ridge, Tennessee 37831, United States
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11
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Ma Z, Jia YG, Zhu XX. Glycopolymers Bearing Galactose and Betulin: Synthesis, Encapsulation, and Lectin Recognition. Biomacromolecules 2017; 18:3812-3818. [DOI: 10.1021/acs.biomac.7b01106] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Zhiyuan Ma
- Department of Chemistry, Université de Montréal, C.P. 6128, Succursale Centre-ville, Montréal, QC H3C 3J7, Canada
| | - Yong-Guang Jia
- Department of Chemistry, Université de Montréal, C.P. 6128, Succursale Centre-ville, Montréal, QC H3C 3J7, Canada
| | - X. X. Zhu
- Department of Chemistry, Université de Montréal, C.P. 6128, Succursale Centre-ville, Montréal, QC H3C 3J7, Canada
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12
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Teratanatorn P, Hoskins R, Swift T, Douglas CWI, Shepherd J, Rimmer S. Binding of Bacteria to Poly(N-isopropylacrylamide) Modified with Vancomycin: Comparison of Behavior of Linear and Highly Branched Polymers. Biomacromolecules 2017; 18:2887-2899. [PMID: 28731679 DOI: 10.1021/acs.biomac.7b00800] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The behavior of a linear copolymer of N-isopropylacrylamide with pendant vancomycin functionality was compared to an analogous highly branched copolymer with vancomycin functionality at the chain ends. Highly branched poly(N-isopropylacrylamide) modified with vancomycin (HB-PNIPAM-van) was synthesized by functionalization of the HB-PNIPAM, prepared using reversible addition-fragmentation chain transfer polymerization. Linear PNIPAM with pendant vancomycin functionality (L-PNIPAM-van) was synthesized by functionalization of poly(N-isopropylacrylamide-co-vinyl benzoic acid). HB-PNIPAM-van aggregated S. aureus effectively, whereas the L-PNIPAM-van polymer did not. It was found that when the HB-PNIPAM-van was incubated with S. aureus the resultant phase transition provided an increase in the intensity of fluorescence of a solvatochromic dye, nile red, added to the system. In contrast, a significantly lower increase in fluorescence intensity was obtained when L-PNIPAM-van was incubated with S. aureus. These data showed that the degree of desolvation of HB-PNIPAM-van was much greater than the desolvation of the linear version. Using microcalorimetry, it was shown that there were no significant differences in the affinities of the polymer ligands for d-Ala-d-Ala and therefore differences in the interactions with bacteria were associated with changes in the probability of access of the polymer bound ligands to the d-Ala-d-Ala dipeptide. The data support the hypothesis that generation of polymer systems that respond to cellular targets, for applications such as cell targeting, detection of pathogens etc., requires the use of branched polymers with ligands situated at the chain ends.
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Affiliation(s)
- Pavintorn Teratanatorn
- Dental School, University of Sheffield , 19 Claremont Crescent, Sheffield, South Yorkshire, U.K. , S10 2TA
| | - Richard Hoskins
- School of Chemistry and Biosciences, University of Bradford , Bradford, West Yorkshire, U.K. , BD1 1DP
| | - Thomas Swift
- School of Chemistry and Biosciences, University of Bradford , Bradford, West Yorkshire, U.K. , BD1 1DP
| | - C W Ian Douglas
- Dental School, University of Sheffield , 19 Claremont Crescent, Sheffield, South Yorkshire, U.K. , S10 2TA
| | - Joanna Shepherd
- Dental School, University of Sheffield , 19 Claremont Crescent, Sheffield, South Yorkshire, U.K. , S10 2TA
| | - Stephen Rimmer
- School of Chemistry and Biosciences, University of Bradford , Bradford, West Yorkshire, U.K. , BD1 1DP
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13
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Timm AC, Halsted MC, Wilmoth JL, Retterer ST. Assembly and Tracking of Microbial Community Development within a Microwell Array Platform. J Vis Exp 2017. [PMID: 28654053 DOI: 10.3791/55701] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
The development of microbial communities depends on a combination of complex deterministic and stochastic factors that can dramatically alter the spatial distribution and activities of community members. We have developed a microwell array platform that can be used to rapidly assemble and track thousands of bacterial communities in parallel. This protocol highlights the utility of the platform and describes its use for optically monitoring the development of simple, two-member communities within an ensemble of arrays within the platform. This demonstration uses two mutants of Pseudomonas aeruginosa, part of a series of mutants developed to study Type VI secretion pathogenicity. Chromosomal inserts of either mCherry or GFP genes facilitate the constitutive expression of fluorescent proteins with distinct emission wavelengths that can be used to monitor community member abundance and location within each microwell. This protocol describes a detailed method for assembling mixtures of bacteria into the wells of the array and using time-lapse fluorescence imaging and quantitative image analysis to measure the relative growth of each member population over time. The seeding and assembly of the microwell platform, the imaging procedures necessary for the quantitative analysis of microbial communities within the array, and the methods that can be used to reveal interactions between microbial species area all discussed.
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Affiliation(s)
| | - Michelle C Halsted
- Bredesen Center for Interdisciplinary Research and Graduate Education, University of Tennessee
| | | | - Scott T Retterer
- Biosciences Division, Oak Ridge National Laboratory; Center for Nanophase Materials Sciences, Oak Ridge National Laboratory;
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14
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Aden B, Kite CM, Hopkins BW, Zetterberg A, Lokitz BS, Ankner JF, Kilbey SM. Assessing Chemical Transformation of Reactive, Interfacial Thin Films Made of End-Tethered Poly(2-vinyl-4,4-dimethyl azlactone) (PVDMA) Chains. Macromolecules 2017. [DOI: 10.1021/acs.macromol.6b01999] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Affiliation(s)
- Bethany Aden
- Department of Chemistry and ‡Department of Chemical and Biomolecular Engineering, University of Tennessee, Knoxville, Tennessee 37996, United States
- Center for Nanophase Materials Sciences and ∥Spallation Neutron Source, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Camille M. Kite
- Department of Chemistry and ‡Department of Chemical and Biomolecular Engineering, University of Tennessee, Knoxville, Tennessee 37996, United States
- Center for Nanophase Materials Sciences and ∥Spallation Neutron Source, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Benjamin W. Hopkins
- Department of Chemistry and ‡Department of Chemical and Biomolecular Engineering, University of Tennessee, Knoxville, Tennessee 37996, United States
- Center for Nanophase Materials Sciences and ∥Spallation Neutron Source, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Anna Zetterberg
- Department of Chemistry and ‡Department of Chemical and Biomolecular Engineering, University of Tennessee, Knoxville, Tennessee 37996, United States
- Center for Nanophase Materials Sciences and ∥Spallation Neutron Source, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Bradley S. Lokitz
- Department of Chemistry and ‡Department of Chemical and Biomolecular Engineering, University of Tennessee, Knoxville, Tennessee 37996, United States
- Center for Nanophase Materials Sciences and ∥Spallation Neutron Source, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - John F. Ankner
- Department of Chemistry and ‡Department of Chemical and Biomolecular Engineering, University of Tennessee, Knoxville, Tennessee 37996, United States
- Center for Nanophase Materials Sciences and ∥Spallation Neutron Source, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - S. Michael Kilbey
- Department of Chemistry and ‡Department of Chemical and Biomolecular Engineering, University of Tennessee, Knoxville, Tennessee 37996, United States
- Center for Nanophase Materials Sciences and ∥Spallation Neutron Source, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
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15
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Choi JW, Carter MCD, Wei W, Kanimozi C, Speetjens FW, Mahanthappa MK, Lynn DM, Gopalan P. Self-Assembly and Post-Fabrication Functionalization of Microphase Separated Thin Films of a Reactive Azlactone-Containing Block Copolymer. Macromolecules 2016. [DOI: 10.1021/acs.macromol.6b01734] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Jonathan W. Choi
- Department
of Materials Science and Engineering, 1509 University Avenue, University of Wisconsin—Madison, Madison, Wisconsin 53706, United States
| | - Matthew C. D. Carter
- Department
of Chemistry, 1101 University
Avenue, University of Wisconsin—Madison, Madison, Wisconsin 53706, United States
| | - Wei Wei
- Department
of Materials Science and Engineering, 1509 University Avenue, University of Wisconsin—Madison, Madison, Wisconsin 53706, United States
| | - Catherine Kanimozi
- Department
of Materials Science and Engineering, 1509 University Avenue, University of Wisconsin—Madison, Madison, Wisconsin 53706, United States
| | - Frank W. Speetjens
- Department
of Chemistry, 1101 University
Avenue, University of Wisconsin—Madison, Madison, Wisconsin 53706, United States
| | - Mahesh K. Mahanthappa
- Department
of Chemistry, 1101 University
Avenue, University of Wisconsin—Madison, Madison, Wisconsin 53706, United States
- Department of Chemical Engineering & Materials Science, 421 Washington Ave. S.E., University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - David M. Lynn
- Department
of Chemistry, 1101 University
Avenue, University of Wisconsin—Madison, Madison, Wisconsin 53706, United States
- Department of Chemical & Biological Engineering, 1415 Engineering Drive, University of Wisconsin—Madison, Madison, Wisconsin 53706, United States
| | - Padma Gopalan
- Department
of Materials Science and Engineering, 1509 University Avenue, University of Wisconsin—Madison, Madison, Wisconsin 53706, United States
- Department
of Chemistry, 1101 University
Avenue, University of Wisconsin—Madison, Madison, Wisconsin 53706, United States
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16
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Zayas-Gonzalez YM, Lynn DM. Degradable Amine-Reactive Coatings Fabricated by the Covalent Layer-by-Layer Assembly of Poly(2-vinyl-4,4-dimethylazlactone) with Degradable Polyamine Building Blocks. Biomacromolecules 2016; 17:3067-75. [PMID: 27525718 DOI: 10.1021/acs.biomac.6b00975] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
We report the fabrication of reactive and degradable cross-linked polymer multilayers by the reactive/covalent layer-by-layer assembly of a non-degradable azlactone-functionalized polymer [poly(2-vinyl-4,4-dimethylazlactone), PVDMA] with hydrolytically or enzymatically degradable polyamine building blocks. Fabrication of multilayers using PVDMA and a hydrolytically degradable poly(β-amino ester) (PBAE) containing primary amine side chains yielded multilayers (∼100 nm thick) that degraded over ∼12 days in physiologically relevant media. Physicochemical characterization and studies on stable films fabricated using PVDMA and an analogous non-degradable poly(amidoamine) suggested that erosion occurred by chemical hydrolysis of backbone esters in the PBAE components of these assemblies. These degradable assemblies also contained residual amine-reactive azlactone functionality that could be used to impart new functionality to the coatings post-fabrication. Cross-linked multilayers fabricated using PVDMA and the enzymatically degradable polymer poly(l-lysine) were structurally stable for prolonged periods in physiological media, but degraded over ∼24 h when the enzyme trypsin was added. Past studies demonstrate that multilayers fabricated using PVDMA and non-degradable polyamines [e.g., poly(ethylenimine)] enable the design and patterning of useful nano/biointerfaces and other materials that are structurally stable in physiological media. The introduction of degradable functionality into PVDMA-based multilayers creates opportunities to exploit the reactivity of azlactone groups for the design of reactive materials and functional coatings that degrade or erode in environments that are relevant in biomedical, biotechnological, and environmental contexts. This "degradable building block" strategy should be general; we anticipate that this approach can also be extended to the design of amine-reactive multilayers that degrade upon exposure to specific chemical triggers, selective enzymes, or contact with cells by judicious design of the degradable polyamine building blocks used to fabricate the coatings.
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Affiliation(s)
- Yashira M Zayas-Gonzalez
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison , 1415 Engineering Drive, Madison, Wisconsin 53706, United States , and
| | - David M Lynn
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison , 1415 Engineering Drive, Madison, Wisconsin 53706, United States , and.,Department of Chemistry, University of Wisconsin-Madison , 1101 University Avenue, Madison, Wisconsin 53706, United States
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17
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Carter MCD, Jennings J, Appadoo V, Lynn DM. Synthesis and Characterization of Backbone Degradable Azlactone-Functionalized Polymers. Macromolecules 2016. [DOI: 10.1021/acs.macromol.6b01212] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Affiliation(s)
- Matthew C. D. Carter
- Department
of Chemistry, University of Wisconsin—Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
| | - James Jennings
- Department
of Chemical and Biological Engineering, University of Wisconsin—Madison, 1415 Engineering Drive, Madison, Wisconsin 53706, United States
| | - Visham Appadoo
- Department
of Chemistry, University of Wisconsin—Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
| | - David M. Lynn
- Department
of Chemistry, University of Wisconsin—Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
- Department
of Chemical and Biological Engineering, University of Wisconsin—Madison, 1415 Engineering Drive, Madison, Wisconsin 53706, United States
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18
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Hansen RH, Timm AC, Timm CM, Bible AN, Morrell-Falvey JL, Pelletier DA, Simpson ML, Doktycz MJ, Retterer ST. Stochastic Assembly of Bacteria in Microwell Arrays Reveals the Importance of Confinement in Community Development. PLoS One 2016; 11:e0155080. [PMID: 27152511 PMCID: PMC4859483 DOI: 10.1371/journal.pone.0155080] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2016] [Accepted: 04/24/2016] [Indexed: 12/26/2022] Open
Abstract
The structure and function of microbial communities is deeply influenced by the physical and chemical architecture of the local microenvironment and the abundance of its community members. The complexity of this natural parameter space has made characterization of the key drivers of community development difficult. In order to facilitate these characterizations, we have developed a microwell platform designed to screen microbial growth and interactions across a wide variety of physical and initial conditions. Assembly of microbial communities into microwells was achieved using a novel biofabrication method that exploits well feature sizes for control of innoculum levels. Wells with incrementally smaller size features created populations with increasingly larger variations in inoculum levels. This allowed for reproducible growth measurement in large (20 μm diameter) wells, and screening for favorable growth conditions in small (5, 10 μm diameter) wells. We demonstrate the utility of this approach for screening and discovery using 5 μm wells to assemble P. aeruginosa colonies across a broad distribution of innoculum levels, and identify those conditions that promote the highest probability of survivial and growth under spatial confinement. Multi-member community assembly was also characterized to demonstrate the broad potential of this platform for studying the role of member abundance on microbial competition, mutualism and community succession.
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Affiliation(s)
- Ryan H Hansen
- Kansas State University, Manhattan, Kansas, United States of America.,The University of Tennessee, Knoxville, Tennessee, United States of America
| | - Andrea C Timm
- Oak Ridge National Laboratory, Oak Ridge, Tennessee, United States of America
| | - Collin M Timm
- Oak Ridge National Laboratory, Oak Ridge, Tennessee, United States of America
| | - Amber N Bible
- Oak Ridge National Laboratory, Oak Ridge, Tennessee, United States of America
| | - Jennifer L Morrell-Falvey
- The University of Tennessee, Knoxville, Tennessee, United States of America.,Oak Ridge National Laboratory, Oak Ridge, Tennessee, United States of America
| | - Dale A Pelletier
- Oak Ridge National Laboratory, Oak Ridge, Tennessee, United States of America
| | - Michael L Simpson
- The University of Tennessee, Knoxville, Tennessee, United States of America.,Oak Ridge National Laboratory, Oak Ridge, Tennessee, United States of America
| | - Mitchel J Doktycz
- The University of Tennessee, Knoxville, Tennessee, United States of America.,Oak Ridge National Laboratory, Oak Ridge, Tennessee, United States of America
| | - Scott T Retterer
- The University of Tennessee, Knoxville, Tennessee, United States of America.,Oak Ridge National Laboratory, Oak Ridge, Tennessee, United States of America
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19
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Barkakaty B, Browning KL, Sumpter B, Uhrig D, Karpisova I, Harman KW, Ivanov I, Hensley DK, Messman JM, Kilbey SM, Lokitz BS. Amidine-Functionalized Poly(2-vinyl-4,4-dimethylazlactone) for Selective and Efficient CO2 Fixing. Macromolecules 2016. [DOI: 10.1021/acs.macromol.5b02483] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Balaka Barkakaty
- Center
for Nanophase Materials Sciences, Oak Ridge National Laboratory, One Bethel Valley Road, Oak Ridge, Tennessee 37831, United States
| | | | - Bobby Sumpter
- Center
for Nanophase Materials Sciences, Oak Ridge National Laboratory, One Bethel Valley Road, Oak Ridge, Tennessee 37831, United States
| | - David Uhrig
- Center
for Nanophase Materials Sciences, Oak Ridge National Laboratory, One Bethel Valley Road, Oak Ridge, Tennessee 37831, United States
| | - Ivana Karpisova
- Department
of Nuclear Physics and Biophysics, Faculty of Mathematics, Physics
and Informatics, Comenius University, 84248 Bratislava, Slovakia
| | - Kevin W. Harman
- Center
for Nanophase Materials Sciences, Oak Ridge National Laboratory, One Bethel Valley Road, Oak Ridge, Tennessee 37831, United States
| | - Ilia Ivanov
- Center
for Nanophase Materials Sciences, Oak Ridge National Laboratory, One Bethel Valley Road, Oak Ridge, Tennessee 37831, United States
| | - Dale K. Hensley
- Center
for Nanophase Materials Sciences, Oak Ridge National Laboratory, One Bethel Valley Road, Oak Ridge, Tennessee 37831, United States
| | - Jamie M. Messman
- Center
for Nanophase Materials Sciences, Oak Ridge National Laboratory, One Bethel Valley Road, Oak Ridge, Tennessee 37831, United States
| | | | - Bradley S. Lokitz
- Center
for Nanophase Materials Sciences, Oak Ridge National Laboratory, One Bethel Valley Road, Oak Ridge, Tennessee 37831, United States
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20
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Timm CM, Hansen RR, Doktycz MJ, Retterer ST, Pelletier DA. Microstencils to generate defined, multi-species patterns of bacteria. BIOMICROFLUIDICS 2015; 9:064103. [PMID: 26594264 PMCID: PMC4644145 DOI: 10.1063/1.4935938] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2015] [Accepted: 11/05/2015] [Indexed: 05/21/2023]
Abstract
Microbial communities are complex heterogeneous systems that are influenced by physical and chemical interactions with their environment, host, and community members. Techniques that facilitate the quantitative evaluation of how microscale organization influences the morphogenesis of multispecies communities could provide valuable insights into the dynamic behavior and organization of natural communities, the design of synthetic environments for multispecies culture, and the engineering of artificial consortia. In this work, we demonstrate a method for patterning microbes into simple arrangements that allow the quantitative measurement of growth dynamics as a function of their proximity to one another. The method combines parylene-based liftoff techniques with microfluidic delivery to simultaneously pattern multiple bacterial species with high viability using low-cost, customizable methods. Quantitative measurements of bacterial growth for two competing isolates demonstrate that spatial coordination can play a critical role in multispecies growth and structure.
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Affiliation(s)
- Collin M Timm
- Biosciences Division, Oak Ridge National Laboratory , Oak Ridge, Tennessee 37831, USA
| | - Ryan R Hansen
- Department of Chemical Engineering, Kansas State University , Manhattan, Kansas 66506, USA
| | | | | | - Dale A Pelletier
- Biosciences Division, Oak Ridge National Laboratory , Oak Ridge, Tennessee 37831, USA
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21
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Microstructured block copolymer surfaces for control of microbe adhesion and aggregation. BIOSENSORS-BASEL 2015; 4:63-75. [PMID: 25587410 PMCID: PMC4264371 DOI: 10.3390/bios4010063] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/23/2014] [Revised: 03/05/2014] [Accepted: 03/10/2014] [Indexed: 01/26/2023]
Abstract
The attachment and arrangement of microbes onto a substrate is influenced by both the biochemical and physical surface properties. In this report, we develop lectin-functionalized substrates containing patterned, three-dimensional polymeric structures of varied shapes and densities and use these to investigate the effects of topology and spatial confinement on lectin-mediated microbe immobilization. Films of poly(glycidyl methacrylate)-block-4,4-dimethyl-2-vinylazlactone (PGMA-b-PVDMA) were patterned on silicon surfaces into line arrays or square grid patterns with 5 μm wide features and varied pitch. The patterned films had three-dimensional geometries with 900 nm film thickness. After surface functionalization with wheat germ agglutinin, the size of Pseudomonas fluorescens aggregates immobilized was dependent on the pattern dimensions. Films patterned as parallel lines or square grids with a pitch of 10 μm or less led to the immobilization of individual microbes with minimal formation of aggregates. Both geometries allowed for incremental increases in aggregate size distribution with each increase in pitch. These engineered surfaces combine spatial confinement with affinity-based capture to control the extent of microbe adhesion and aggregation, and can also be used as a platform to investigate intercellular interactions and biofilm formation in microbial populations of controlled sizes.
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22
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Kumar R, Lokitz BS, Sides SW, Chen J, Heller WT, Ankner JF, Browning JF, Kilbey II SM, Sumpter BG. Microphase separation in thin films of lamellar forming polydisperse di-block copolymers. RSC Adv 2015. [DOI: 10.1039/c5ra00974j] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Effects of polydispersity in chain lengths on microphase separation in thin films of di-block copolymers are studied using self-consistent field theory (SCFT) and neutron reflectivity experiments.
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Affiliation(s)
- Rajeev Kumar
- Computer Science and Mathematics Division
- Oak Ridge National Lab
- Oak Ridge
- USA
- Center for Nanophase Materials Sciences
| | - Bradley S. Lokitz
- Center for Nanophase Materials Sciences
- Oak Ridge National Laboratory
- Oak Ridge
- USA
| | | | - Jihua Chen
- Center for Nanophase Materials Sciences
- Oak Ridge National Laboratory
- Oak Ridge
- USA
| | | | - John F. Ankner
- Spallation Neutron Source
- Oak Ridge National Laboratory
- Oak Ridge
- USA
| | | | | | - Bobby G. Sumpter
- Computer Science and Mathematics Division
- Oak Ridge National Lab
- Oak Ridge
- USA
- Center for Nanophase Materials Sciences
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23
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Bai L, Tan L, Chen L, Liu S, Wang Y. Preparation and characterizations of poly(2-methyl-2-oxazoline) based antifouling coating by thermally induced immobilization. J Mater Chem B 2014; 2:7785-7794. [DOI: 10.1039/c4tb01383b] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Poly[(2-methyl-2-oxazoline)-random-glycidylmethacrylate] was immobilized on a silicon/glass surface via a simple annealing procedure to obtain a covalent and cross-linked antifouling coating.
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Affiliation(s)
- Longchao Bai
- CAS Key Laboratory of Soft Matter Chemistry
- Department of Polymer Science and Engineering
- University of Science and Technology of China
- Hefei 230026, P. R. China
| | - Lin Tan
- CAS Key Laboratory of Soft Matter Chemistry
- Department of Polymer Science and Engineering
- University of Science and Technology of China
- Hefei 230026, P. R. China
| | - Lijuan Chen
- CAS Key Laboratory of Soft Matter Chemistry
- Department of Polymer Science and Engineering
- University of Science and Technology of China
- Hefei 230026, P. R. China
| | - Songtao Liu
- CAS Key Laboratory of Soft Matter Chemistry
- Department of Polymer Science and Engineering
- University of Science and Technology of China
- Hefei 230026, P. R. China
| | - Yanmei Wang
- CAS Key Laboratory of Soft Matter Chemistry
- Department of Polymer Science and Engineering
- University of Science and Technology of China
- Hefei 230026, P. R. China
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