Nanoparticle Fabrication on Bacterial Microcompartment Surface for the Development of Hybrid Enzyme-Inorganic Catalyst

AbstractUpscaling of nanoparticle fabrication by sputtering into an ionic liquid is shown for the example of Cu. Long-time sputtering (24 h) into a large amount (50 mL) of the ionic liquid 1-butyl-3-methylimidazolium bis-(trifluoromethylsulfonyl)imide [Bmim][(Tf)2 N] yields an amount of approximately 1 g Cu nanoparticles (mean spherical diameter (2.6 ± 1.1) nm), stabilized in ionic liquid without agglomerations. Extraction of Cu nanoparticles from the stabilizing ionic liquid was performed with the capping agent hexadecylamine. Extracted particles could be redispersed in other solvents, thus enabling applications of sputtered nanoparticles beyond ionic liquids.

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Substrate channels revealed in the trimericLactobacillus reuteribacterial microcompartment shell protein PduB

Acta Crystallographica Section D Biological Crystallography ◽

10.1107/s0907444912039315 ◽

2012 ◽

Vol 68 (12) ◽

pp. 1642-1652 ◽

Cited By ~ 37

Author(s):

Allan Pang ◽

Mingzhi Liang ◽

Michael B. Prentice ◽

Richard W. Pickersgill

Keyword(s):

Tandem Repeats ◽

Lactobacillus Reuteri ◽

Protein Complexes ◽

Protein Subunits ◽

Shell Protein ◽

Domain Structures ◽

Bacterial Microcompartment ◽

Major Shell ◽

Carbon Molecules ◽

Trimeric Structure

Lactobacillus reuterimetabolizes two similar three-carbon molecules, 1,2-propanediol and glycerol, within closed polyhedral subcellular bacterial organelles called bacterial microcompartments (metabolosomes). The outer shell of the propanediol-utilization (Pdu) metabolosome is composed of hundreds of mainly hexagonal protein complexes made from six types of protein subunits that share similar domain structures. The structure of the bacterial microcompartment protein PduB has a tandem structural repeat within the subunit and assembles into a trimer with pseudo-hexagonal symmetry. This trimeric structure forms sheets in the crystal lattice and is able to fit within a polymeric sheet of the major shell component PduA to assemble a facet of the polyhedron. There are three pores within the trimer and these are formed between the tandem repeats within the subunits. The structure shows that each of these pores contains three glycerol molecules that interact with conserved residues, strongly suggesting that these subunit pores channel glycerol substrate into the metabolosome. In addition to the observation of glycerol occupying the subunit channels, the presence of glycerol on the molecular threefold symmetry axis suggests a role in locking closed the central region.

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Silver Nanoparticle Fabrication by Laser Ablation in Polyvinyl Alcohol Solutions

Chinese Physics Letters ◽

10.1088/0256-307x/31/7/077803 ◽

2014 ◽

Vol 31 (7) ◽

pp. 077803 ◽

Cited By ~ 10

Author(s):

Halimah Mohamed. K ◽

Mahmoud Goodarz Naseri ◽

Amir Reza Sadrolhosseini ◽

Arash Dehzangi ◽

Ahmad Kamalianfar ◽

...

Keyword(s):

Laser Ablation ◽

Polyvinyl Alcohol ◽

Silver Nanoparticle ◽

Nanoparticle Fabrication

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Engineering Bacterial Microcompartment Shells: Chimeric Shell Proteins and Chimeric Carboxysome Shells

ACS Synthetic Biology ◽

10.1021/sb500226j ◽

2014 ◽

Vol 4 (4) ◽

pp. 444-453 ◽

Cited By ~ 58

Author(s):

Fei Cai ◽

Markus Sutter ◽

Susan L. Bernstein ◽

James N. Kinney ◽

Cheryl A. Kerfeld

Keyword(s):

Bacterial Microcompartment ◽

Shell Proteins

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A Bacterial Microcompartment Is Used for Choline Fermentation byEscherichia coli536

Journal of Bacteriology ◽

10.1128/jb.00764-17 ◽

2018 ◽

Vol 200 (10) ◽

Cited By ~ 12

Author(s):

Taylor I. Herring ◽

Tiffany N. Harris ◽

Chiranjit Chowdhury ◽

Sujit Kumar Mohanty ◽

Thomas A. Bobik

Keyword(s):

Electron Microscopy ◽

Heart Disease ◽

Gene Cluster ◽

Transcriptional Regulator ◽

Human Gut ◽

Content Type ◽

E Coli ◽

Bacterial Microcompartment ◽

New Type ◽

Insight Into

ABSTRACTBacterial choline degradation in the human gut has been associated with cancer and heart disease. In addition, recent studies found that a bacterial microcompartment is involved in choline utilization byProteusandDesulfovibriospecies. However, many aspects of this process have not been fully defined. Here, we investigate choline degradation by the uropathogenEscherichia coli536. Growth studies indicatedE. coli536 degrades choline primarily by fermentation. Electron microscopy indicated that a bacterial microcompartment was used for this process. Bioinformatic analyses suggested that the choline utilization (cut) gene cluster ofE. coli536 includes two operons, one containing three genes and a main operon of 13 genes. Regulatory studies indicate that thecutXgene encodes a positive transcriptional regulator required for induction of the maincutoperon in response to choline supplementation. Each of the 16 genes in thecutcluster was individually deleted, and phenotypes were examined. ThecutX,cutY,cutF,cutO,cutC,cutD,cutU, andcutVgenes were required for choline degradation, but the remaining genes of thecutcluster were not essential under the conditions used. The reasons for these varied phenotypes are discussed.IMPORTANCEHere, we investigate choline degradation inE. coli536. These studies provide a basis for understanding a new type of bacterial microcompartment and may provide deeper insight into the link between choline degradation in the human gut and cancer and heart disease. These are also the first studies of choline degradation inE. coli536, an organism for which sophisticated genetic analysis methods are available. In addition, thecutgene cluster ofE. coli536 is located in pathogenicity island II (PAI-II536) and hence might contribute to pathogenesis.

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Linking the Salmonella enterica 1,2-propanediol utilization bacterial microcompartment shell to the enzymatic core via the shell protein PduB

10.1101/2021.10.27.466122 ◽

2021 ◽

Author(s):

Nolan W Kennedy ◽

Carolyn E Mills ◽

Charlotte H Abrahamson ◽

Andre Archer ◽

Michael C Jewett ◽

...

Keyword(s):

Salmonella Enterica ◽

Carbon Sources ◽

Enzyme Concentration ◽

Fluorescent Reporters ◽

Shell Protein ◽

Bacterial Microcompartment ◽

Enzyme Encapsulation ◽

Transmission Electron ◽

Serovar Typhimurium ◽

Enzymatic Machinery

Bacterial microcompartments (MCPs) are protein-based organelles that house the enzymatic machinery for metabolism of niche carbon sources, allowing enteric pathogens to outcompete native microbiota during host colonization. While much progress has been made toward understanding MCP biogenesis, questions still remain regarding the mechanism by which core MCP enzymes are enveloped within the MCP protein shell. Here we explore the hypothesis that the shell protein PduB is responsible for linking the shell of the 1,2-propanediol utilization (Pdu) MCP from Salmonella enterica serovar Typhimurium LT2 to its enzymatic core. Using fluorescent reporters, we demonstrate that all members of the Pdu enzymatic core are encapsulated in Pdu MCPs. We also demonstrate that PduB is the sole protein responsible for linking the entire Pdu enzyme core to the MCP shell. Using MCP purifications, transmission electron microscopy, and fluorescence microscopy we find that shell assembly can be decoupled from the enzymatic core, as apparently empty MCPs are formed in Salmonella strains lacking PduB. Mutagenesis studies also reveal that PduB is incorporated into the Pdu MCP shell via a conserved, lysine-mediated hydrogen bonding mechanism. Finally, growth assays and systems-level pathway modeling reveal that unencapsulated pathway performance is strongly impacted by enzyme concentration, highlighting the importance of minimizing polar effects when conducting these functional assays. Together, these results provide insight into the mechanism of enzyme encapsulation within Pdu MCPs and demonstrate that the process of enzyme encapsulation and shell assembly are separate processes in this system, a finding that will aid future efforts to understand MCP biogenesis.

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