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Tang H, Ju X, Zhao J, Li L. Engineering ribose-5-phosphate isomerase B from a central carbon metabolic enzyme to a promising sugar biocatalyst. Appl Microbiol Biotechnol 2021; 105:509-523. [PMID: 33394147 DOI: 10.1007/s00253-020-11075-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2020] [Revised: 12/12/2020] [Accepted: 12/23/2020] [Indexed: 10/22/2022]
Abstract
Ribose-5-phosphate isomerase B (RpiB) was first identified in the pentose phosphate pathway responsible for the inter-conversion of ribose-5-phosphate and ribulose-5-phosphate. Though there are seldom key enzymes in central carbon metabolic system developed as useful biocatalysts, RpiB with the advantages of wide substrate scope and high stereoselectivity has become a potential biotechnological tool to fulfill the demand of rare sugars currently. In this review, the pivotal roles of RpiB in carbon metabolism are summarized, and their sequence identity and structural similarity are discussed. Substrate binding and catalytic mechanisms are illustrated to provide solid foundations for enzyme engineering. Interesting differences in origin, physiological function, structure, and catalytic mechanism between RpiB and ribose-5-phosphate isomerase A are introduced. Moreover, enzyme engineering efforts for rare sugar production are stressed, and prospects of future development are concluded briefly in the viewpoint of biocatalysis. Aided by the progresses of structural and computational biology, the application of RpiB will be promoted greatly in the preparation of valuable molecules. KEY POINTS: • Detailed illustration of RpiB's vital function in central carbon metabolism. • Potential of RpiB in sequence, substrate scope, and mechanism for application. • Enzyme engineering efforts to promote RpiB in the preparation of rare sugars.
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Affiliation(s)
- Hengtao Tang
- School of Chemistry and Life Sciences, Suzhou University of Science and Technology, No.99 Xuefu Rd., Huqiu district, Suzhou, 215009, Jiangsu Province, People's Republic of China
| | - Xin Ju
- School of Chemistry and Life Sciences, Suzhou University of Science and Technology, No.99 Xuefu Rd., Huqiu district, Suzhou, 215009, Jiangsu Province, People's Republic of China
| | - Jing Zhao
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Hubei Collaborative Innovation Center for Green Transformation of Bio-Resources, Hubei Key Laboratory of Industrial Biotechnology, School of Life Sciences, Hubei University, Wuhan, 430062, People's Republic of China
| | - Liangzhi Li
- School of Chemistry and Life Sciences, Suzhou University of Science and Technology, No.99 Xuefu Rd., Huqiu district, Suzhou, 215009, Jiangsu Province, People's Republic of China.
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2
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Lohrer MF, Liu Y, Hanna DM, Wang KH, Liu FT, Laurence TA, Liu GY. Determination of the Maturation Status of Dendritic Cells by Applying Pattern Recognition to High-Resolution Images. J Phys Chem B 2020; 124:8540-8548. [DOI: 10.1021/acs.jpcb.0c06437] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- Michael F. Lohrer
- Department of Electrical and Computer Engineering, Oakland University, Rochester, Michigan 48309, United States
| | - Yang Liu
- Department of Chemistry, University of California, Davis, California 95616, United States
| | - Darrin M. Hanna
- Department of Electrical and Computer Engineering, Oakland University, Rochester, Michigan 48309, United States
| | - Kang-Hsin Wang
- Department of Chemistry, University of California, Davis, California 95616, United States
- Department of Dermatology, University of California, Davis Medical Center, Sacramento, California 95817, United States
| | - Fu-Tong Liu
- Department of Dermatology, University of California, Davis Medical Center, Sacramento, California 95817, United States
| | - Ted A. Laurence
- Lawrence Livermore National Laboratory, Livermore, California 94550, United States
| | - Gang-yu Liu
- Department of Chemistry, University of California, Davis, California 95616, United States
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3
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Li JR, Ross SS, Liu Y, Liu YX, Wang KH, Chen HY, Liu FT, Laurence TA, Liu GY. Engineered Nanostructures of Haptens Lead to Unexpected Formation of Membrane Nanotubes Connecting Rat Basophilic Leukemia Cells. ACS NANO 2015; 9:6738-6746. [PMID: 26057701 PMCID: PMC4758354 DOI: 10.1021/acsnano.5b02270] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
A recent finding reports that co-stimulation of the high-affinity immunoglobulin E (IgE) receptor (FcεRI) and the chemokine receptor 1 (CCR1) triggered formation of membrane nanotubes among bone-marrow-derived mast cells. The co-stimulation was attained using corresponding ligands: IgE binding antigen and macrophage inflammatory protein 1α (MIP1 α), respectively. However, this approach failed to trigger formation of nanotubes among rat basophilic leukemia (RBL) cells due to the lack of CCR1 on the cell surface (Int. Immunol. 2010, 22 (2), 113-128). RBL cells are frequently used as a model for mast cells and are best known for antibody-mediated activation via FcεRI. This work reports the successful formation of membrane nanotubes among RBLs using only one stimulus, a hapten of 2,4-dinitrophenyl (DNP) molecules, which are presented as nanostructures with our designed spatial arrangements. This observation underlines the significance of the local presentation of ligands in the context of impacting the cellular signaling cascades. In the case of RBL, certain DNP nanostructures suppress antigen-induced degranulation and facilitate the rearrangement of the cytoskeleton to form nanotubes. These results demonstrate an important scientific concept; engineered nanostructures enable cellular signaling cascades, where current technologies encounter great difficulties. More importantly, nanotechnology offers a new platform to selectively activate and/or inhibit desired cellular signaling cascades.
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Affiliation(s)
- Jie-Ren Li
- Department of Chemistry, University of California, Davis, California 95616, United States
| | - Shailise S. Ross
- Department of Chemistry, University of California, Davis, California 95616, United States
| | - Yang Liu
- Department of Chemistry, University of California, Davis, California 95616, United States
| | - Ying X. Liu
- Department of Chemistry, University of California, Davis, California 95616, United States
| | - Kang-hsin Wang
- Department of Chemistry, University of California, Davis, California 95616, United States
| | - Huan-Yuan Chen
- Department of Dermatology, School of Medicine, University of California, Davis, Sacramento, California 95817, United States
- Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan, ROC
| | - Fu-Tong Liu
- Department of Dermatology, School of Medicine, University of California, Davis, Sacramento, California 95817, United States
- Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan, ROC
| | - Ted A. Laurence
- Lawrence Livermore National Laboratory, Livermore, California 94550, United States
| | - Gang-yu Liu
- Department of Chemistry, University of California, Davis, California 95616, United States
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4
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Vuotto C, Donelli G. Field emission scanning electron microscopy of biofilm-growing bacteria involved in nosocomial infections. Methods Mol Biol 2014; 1147:73-84. [PMID: 24664827 DOI: 10.1007/978-1-4939-0467-9_6] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Scanning electron microscopy (SEM) provides useful information on the shape, size, and localization within the biofilm of single bacteria as well as on the steps of biofilm formation process, on bacterial interactions, and on production of extracellular polymeric substances.When biofilms are constituted by microbial species involved in health care-associated infections, information provided by SEM can be fruitfully used not only for basic researches but also for diagnostic purposes.The protocols currently used in our laboratory for biofilm investigation by SEM are reported here. Particularly, the procedures to fix, dehydrate, and metalize in vitro-developed biofilms or ex vivo clinical specimens colonized by biofilm-growing microorganisms are described as well as the advantages of the observation of these samples by field emission scanning electron microscopy.
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Affiliation(s)
- Claudia Vuotto
- Microbial Biofilm Laboratory, Fondazione Santa Lucia IRCCS, Via Ardeatina 306, 00179, Rome, Italy
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5
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Crookes-Goodson WJ, Bojanowski CL, Kay ML, Lloyd PF, Blankemeier A, Hurtubise JM, Singh KM, Barlow DE, Ladouceur HD, Matt Eby D, Johnson GR, Mirau PA, Pehrsson PE, Fraser HL, Russell JN. The impact of culture medium on the development and physiology of biofilms of Pseudomonas fluorescens formed on polyurethane paint. BIOFOULING 2013; 29:601-615. [PMID: 23697763 DOI: 10.1080/08927014.2013.783906] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Microbial biofilms cause the deterioration of polymeric coatings such as polyurethanes (PUs). In many cases, microbes have been shown to use the PU as a nutrient source. The interaction between biofilms and nutritive substrata is complex, since both the medium and the substratum can provide nutrients that affect biofilm formation and biodeterioration. Historically, studies of PU biodeterioration have monitored the planktonic cells in the medium surrounding the material, not the biofilm. This study monitored planktonic and biofilm cell counts, and biofilm morphology, in long-term growth experiments conducted with Pseudomonas fluorescens under different nutrient conditions. Nutrients affected planktonic and biofilm cell numbers differently, and neither was representative of the system as a whole. Microscopic examination of the biofilm revealed the presence of intracellular storage granules in biofilms grown in M9 but not yeast extract salts medium. These granules are indicative of nutrient limitation and/or entry into stationary phase, which may impact the biodegradative capability of the biofilm.
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Affiliation(s)
- Wendy J Crookes-Goodson
- Soft Matter Materials Branch, Materials and Manufacturing Directorate, Air Force Research Laboratory, Wright-Patterson AFB, OH, USA.
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Sanpo N, Berndt CC, Wen C, Wang J. Transition metal-substituted cobalt ferrite nanoparticles for biomedical applications. Acta Biomater 2013; 9:5830-7. [PMID: 23137676 DOI: 10.1016/j.actbio.2012.10.037] [Citation(s) in RCA: 100] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2012] [Revised: 10/26/2012] [Accepted: 10/29/2012] [Indexed: 11/16/2022]
Abstract
Transition metals of copper, zinc, chromium and nickel were substituted into cobalt ferrite nanoparticles via a sol-gel route using citric acid as a chelating agent. The microstructure and elemental composition were characterized using scanning electron microscopy combined with energy-dispersive X-ray spectroscopy. Phase analysis of transition metal-substituted cobalt ferrite nanoparticles was performed via X-ray diffraction. Surface wettability was measured using the water contact angle technique. The surface roughness of all nanoparticles was measured using profilometry. Moreover, thermogravimetric analysis and differential scanning calorimetry were performed to determine the temperature at which the decomposition and oxidation of the chelating agents took place. Results indicated that the substitution of transition metals influences strongly the microstructure, crystal structure and antibacterial property of the cobalt ferrite nanoparticles.
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Affiliation(s)
- Noppakun Sanpo
- Industrial Research Institute Swinburne, Faculty of Engineering and Industrial Sciences, Swinburne University of Technology, Hawthorn, VIC 3122, Australia
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Abstract
Scanning electron microscopy (SEM) has been almost universally applied for the surface examination and characterization of both natural and man-made objects. Although an invasive technique, developments in electron microscopy over the years has given the microscopist a much clearer choice in how invasive the technique will be. With the advent of low vacuum SEM in the 1970s (The environmental cold stage, 1970) and environmental SEM in the late 1980s (J Microsc 160(pt. 1):9-19, 1989), it is now possible in some circumstances to examine samples without preparation. However, for the examination of biological tissue and cells it is still advisable to chemically fix, dehydrate, and coat samples for SEM imaging and analysis. This chapter aims to provide an overview of SEM as an imaging tool, and a general introduction to some of the methods applied for the preparation of samples.
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Deng Z, Weng IC, Li JR, Chen HY, Liu FT, Liu GY. Engineered nanostructures of antigen provide an effective means for regulating mast cell activation. ACS NANO 2011; 5:8672-83. [PMID: 21999491 PMCID: PMC3228856 DOI: 10.1021/nn202510n] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Nanostructures containing 2,4-dinitrophenyl (DNP) as antigen were designed and produced to investigate antibody-mediated activation of mast cells. The design consists of nanogrids of DNP termini inlaid in alkanethiol self-assembled monolayers (SAMs). Using scanning probe-based nanografting, nanometer precision was attained for designed geometry, size, and periodicity. Rat basophilic leukemia (RBL) cells exhibited high sensitivity to the geometry and local environment of DNP presented on these nanostructures. The impact included cellular adherence, spreading, membrane morphology, cytoskeleton structure, and activation. The highest level of spreading and activation was induced by nanogrids of 17 nm line width and 40 nm periodicity, with DNP haptens 1.4 nm above the surroundings. The high efficacy is attributed to two main factors. First, DNP sites in the nanostructure are highly accessible by anti-DNP IgE during recognition. Second, the arrangement or geometry of DNP termini in nanostructures promotes clustering of FcεRI receptors that are prelinked to IgE. The clustering effectively initiates Lyn-mediated signaling cascades, ultimately leading to the degranulation of RBL cells. This work demonstrates an important concept: that nanostructures of ligands provide new and effective cues for directing cellular signaling processes.
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Affiliation(s)
- Zhao Deng
- Department of Chemistry, University of California, Davis, CA 95616
| | - I-Chun Weng
- Department of Dermatology, School of Medicine, Sacramento, University of California at Davis, CA 95817
- Institute of Biomedical Sciences, Academia Sinica, Taiwan, ROC
| | - Jie-Ren Li
- Department of Chemistry, University of California, Davis, CA 95616
| | - Huan-Yuan Chen
- Department of Dermatology, School of Medicine, Sacramento, University of California at Davis, CA 95817
- Institute of Biomedical Sciences, Academia Sinica, Taiwan, ROC
| | - Fu-Tong Liu
- Department of Dermatology, School of Medicine, Sacramento, University of California at Davis, CA 95817
- Institute of Biomedical Sciences, Academia Sinica, Taiwan, ROC
- Author to whom correspondence should be addressed: Phone: (530) 754-9678: Fax: (530) 754-8557
| | - Gang-yu Liu
- Department of Chemistry, University of California, Davis, CA 95616
- Author to whom correspondence should be addressed: Phone: (530) 754-9678: Fax: (530) 754-8557
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Wingender J. Hygienically Relevant Microorganisms in Biofilms of Man-Made Water Systems. ACTA ACUST UNITED AC 2011. [DOI: 10.1007/978-3-642-19940-0_9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
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10
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Adhesion of Aspergillus niger and Penicillium expansumspores on Fez cedar wood substrata. ANN MICROBIOL 2010. [DOI: 10.1007/s13213-010-0045-0] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
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Priester JH, Horst AM, Van de Werfhorst LC, Saleta JL, Mertes LAK, Holden PA. Enhanced visualization of microbial biofilms by staining and environmental scanning electron microscopy. J Microbiol Methods 2006; 68:577-87. [PMID: 17196692 DOI: 10.1016/j.mimet.2006.10.018] [Citation(s) in RCA: 128] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2006] [Accepted: 10/28/2006] [Indexed: 11/29/2022]
Abstract
Bacterial biofilms, i.e. surface-associated cells covered in hydrated extracellular polymeric substances (EPS), are often studied with high-resolution electron microscopy (EM). However, conventional desiccation and high vacuum EM protocols collapse EPS matrices which, in turn, deform biofilm appearances. Alternatively, wet-mode environmental scanning electron microscopy (ESEM) is performed under a moderate vacuum and without biofilm drying. If completely untreated, however, EPS is not electron dense and thus is not resolved well in ESEM. Therefore, this study was towards adapting several conventional SEM staining protocols for improved resolution of biofilms and EPS using ESEM. Three different biofilm types were used: 1) Pseudomonas aeruginosa unsaturated biofilms cultured on membranes, 2) P. aeruginosa cultured in moist sand, and 3) mixed community biofilms cultured on substrates in an estuary. Working with the first specimen type, a staining protocol using ruthenium red, glutaraldehyde, osmium tetroxide and lysine was optimized for best topographic resolution. A quantitative image analysis tool that maps relief, newly adopted here for studying biofilms, was used to compare micrographs. When the optimized staining and ESEM protocols were applied to moist sand cultures and aquatic biofilms, the smoothening effect that bacterial biofilms have on rough sand, and the roughening that aquatic biofilms impart on initially smooth coupons, were each quantifiable. This study thus provides transferable staining and ESEM imaging protocols suitable for a wide range of biofilms, plus a novel tool for quantifying biofilm image data.
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Affiliation(s)
- John H Priester
- Donald Bren School of Environmental Science and Management, University of California, Santa Barbara, CA 93106-5131, USA
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12
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Chmielewski RAN, Frank JF. Biofilm Formation and Control in Food Processing Facilities. Compr Rev Food Sci Food Saf 2003; 2:22-32. [PMID: 33451238 DOI: 10.1111/j.1541-4337.2003.tb00012.x] [Citation(s) in RCA: 383] [Impact Index Per Article: 18.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Microorganisms on wet surfaces have the ability to aggregate, grow into microcolonies, and produce biofilm. Growth of biofilms in food processing environments leads to increased opportunity for microbial contamination of the processed product. These biofilms may contain spoilage and pathogenic microorganisms. Microorganisms within biofilms are protected from sanitizers increasing the likelihood of survival and subsequent contamination of food. This increases the risk of reduced shelf life and disease transmission. Extracellular polymeric substances associated with biofilm that are not removed by cleaning provide attachment sites for microorganisms newly arrived to the cleaned system. Biofilm formation can also cause the impairment of heat transfer and corrosion to metal surfaces. Some of the methods used to control biofilm formation include mechanical and manual cleaning, chemical cleaning and sanitation, and application of hot water.
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Affiliation(s)
- R A N Chmielewski
- The authors are with the Dept. of Food Science and Technology, Center for Food Safety, Univ. of Georgia, Athens, GA 30602. Direct inquiries to author Frank (E-mail: )
| | - J F Frank
- The authors are with the Dept. of Food Science and Technology, Center for Food Safety, Univ. of Georgia, Athens, GA 30602. Direct inquiries to author Frank (E-mail: )
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Chandra J, Kuhn DM, Mukherjee PK, Hoyer LL, McCormick T, Ghannoum MA. Biofilm formation by the fungal pathogen Candida albicans: development, architecture, and drug resistance. J Bacteriol 2001; 183:5385-94. [PMID: 11514524 PMCID: PMC95423 DOI: 10.1128/jb.183.18.5385-5394.2001] [Citation(s) in RCA: 1091] [Impact Index Per Article: 47.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2001] [Accepted: 06/27/2001] [Indexed: 01/15/2023] Open
Abstract
Biofilms are a protected niche for microorganisms, where they are safe from antibiotic treatment and can create a source of persistent infection. Using two clinically relevant Candida albicans biofilm models formed on bioprosthetic materials, we demonstrated that biofilm formation proceeds through three distinct developmental phases. These growth phases transform adherent blastospores to well-defined cellular communities encased in a polysaccharide matrix. Fluorescence and confocal scanning laser microscopy revealed that C. albicans biofilms have a highly heterogeneous architecture composed of cellular and noncellular elements. In both models, antifungal resistance of biofilm-grown cells increased in conjunction with biofilm formation. The expression of agglutinin-like (ALS) genes, which encode a family of proteins implicated in adhesion to host surfaces, was differentially regulated between planktonic and biofilm-grown cells. The ability of C. albicans to form biofilms contrasts sharply with that of Saccharomyces cerevisiae, which adhered to bioprosthetic surfaces but failed to form a mature biofilm. The studies described here form the basis for investigations into the molecular mechanisms of Candida biofilm biology and antifungal resistance and provide the means to design novel therapies for biofilm-based infections.
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Affiliation(s)
- J Chandra
- Center for Medical Mycology, University Hospitals of Cleveland, and Department of Dermatology, Case Western Reserve University, Cleveland, Ohio 44106, USA
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Danese PN, Pratt LA, Kolter R. Exopolysaccharide production is required for development of Escherichia coli K-12 biofilm architecture. J Bacteriol 2000; 182:3593-6. [PMID: 10852895 PMCID: PMC101973 DOI: 10.1128/jb.182.12.3593-3596.2000] [Citation(s) in RCA: 435] [Impact Index Per Article: 18.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Although exopolysaccharides (EPSs) are a large component of bacterial biofilms, their contribution to biofilm structure and function has been examined for only a few organisms. In each of these cases EPS has been shown to be required for cellular attachment to abiotic surfaces. Here, we undertook a genetic approach to examine the potential role of colanic acid, an EPS of Escherichia coli K-12, in biofilm formation. Strains either proficient or deficient in colanic acid production were grown and allowed to adhere to abiotic surfaces and were then examined both macroscopically and microscopically. Surprisingly, we found that colanic acid production is not required for surface attachment. Rather, colanic acid is critical for the formation of the complex three-dimensional structure and depth of E. coli biofilms.
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Affiliation(s)
- P N Danese
- Department of Microbiology and Molecular Genetics, Harvard Medical School, Boston, Massachusetts 02115, USA
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Abstract
Ruthenium red, a promising cationic reagent for electron microscopy (EM), has long been an important tool in histology. The reagent was initially used by botanists as a semispecific stain for pectic substances, but it has gradually been embraced by investigators in microbiology and the animal sciences as a stain for anionic glycosylated polymeric substances. Luft developed a reliable method and demonstrated that ruthenium red was a useful reagent for visualizing ultrastructural detail. Many investigators, using modifications of Luft's approach, have identified numerous applications for this important reagent. Ruthenium red has been used to show the ultrastructural detail of bacterial glycocalyces. Strong, sharp and consistent observations of this ultrastructural component of the bacterial cell have given a better understanding its fibrous anionic matrix. Any variations in staining owing to artifactual alteration of the fine delicate ultrastructural features have been overcome by incorporation of diamine lysine into ruthenium red methods, thus providing flexible processing times under less than ideal laboratory sampling conditions. Ruthenium red has broad utility in the biological sciences, and in combination with lysine, it is an excellent EM stain for enhanced visualization of bacterial glycocalyx from culture or from clinical specimens.
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Affiliation(s)
- T A Fassel
- Core Electron Microscope Unit, The Scripps Research Institute, La Jolla, California 92037, USA
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