1
|
Liu Z, Li K, Li J, Zhuang Z, Guo L, Bai L. Characterization and functional evidence for Orf2 of Streptomyces sp. 139 as a novel dipeptidase E. Appl Microbiol Biotechnol 2024; 108:326. [PMID: 38717487 PMCID: PMC11078827 DOI: 10.1007/s00253-024-13161-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2023] [Revised: 04/17/2024] [Accepted: 04/24/2024] [Indexed: 05/12/2024]
Abstract
Aspartyl dipeptidase (dipeptidase E) can hydrolyze Asp-X dipeptides (where X is any amino acid), and the enzyme plays a key role in the degradation of peptides as nutrient sources. Dipeptidase E remains uncharacterized in Streptomyces. Orf2 from Streptomyces sp. 139 is located in the exopolysaccharide biosynthesis gene cluster, which may be a novel dipeptidase E with "S134-H170-D198" catalytic triad by sequence and structure comparison. Herein, recombinant Orf2 was expressed in E. coli and characterized dipeptidase E activity using the Asp-ρNA substrate. The optimal pH and temperature for Orf2 are 7.5 and 40 ℃; Vmax and Km of Orf2 are 0.0787 mM·min-1 and 1.709 mM, respectively. Orf2 exhibits significant degradation activities to Asp-Gly-Gly, Asp-Leu, Asp-His, and isoAsp-Leu and minimal activities to Asp-Pro and Asp-Ala. Orf2 contains a Ser-His-Asp catalytic triad characterized by point mutation. In addition, the Asp147 residue of Orf2 is also proven to be critical for the enzyme's activity through molecular docking and point mutation. Transcriptome analysis reveals the upregulation of genes associated with ribosomes, amino acid biosynthesis, and aminoacyl-tRNA biosynthesis in the orf2 mutant strain. Compared with the orf2 mutant strain and WT, the yield of crude polysaccharide does not change significantly. However, crude polysaccharides from the orf2 mutant strain exhibit a wider range of molecular weight distribution. The results indicate that the Orf2 links nutrient stress to secondary metabolism as a novel dipeptidase E. KEY POINTS: • A novel dipeptidase E with a Ser-His-Asp catalytic triad was characterized from Streptomyces sp. 139. • Orf2 was involved in peptide metabolism both in vitro and in vivo. • Orf2 linked nutrient stress to mycelia formation and secondary metabolism in Streptomyces.
Collapse
Affiliation(s)
- Zhe Liu
- CAMS Key Laboratory of Synthetic Biology for Drug Innovation, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, 100050, China
- NHC Key Laboratory of Biotechnology of Antibiotics, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, 100050, China
| | - Kemeng Li
- CAMS Key Laboratory of Synthetic Biology for Drug Innovation, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, 100050, China
- NHC Key Laboratory of Biotechnology of Antibiotics, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, 100050, China
| | - Jialin Li
- CAMS Key Laboratory of Synthetic Biology for Drug Innovation, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, 100050, China
- NHC Key Laboratory of Biotechnology of Antibiotics, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, 100050, China
| | - Zhuochen Zhuang
- CAMS Key Laboratory of Synthetic Biology for Drug Innovation, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, 100050, China
- NHC Key Laboratory of Biotechnology of Antibiotics, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, 100050, China
| | - Lianhong Guo
- CAMS Key Laboratory of Synthetic Biology for Drug Innovation, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, 100050, China
- NHC Key Laboratory of Biotechnology of Antibiotics, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, 100050, China
| | - Liping Bai
- CAMS Key Laboratory of Synthetic Biology for Drug Innovation, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, 100050, China.
- NHC Key Laboratory of Biotechnology of Antibiotics, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, 100050, China.
| |
Collapse
|
2
|
Influence of Consistency and Composition of Growth Medium on Surface Physicochemical Properties of Streptomyces. JOURNAL OF PURE AND APPLIED MICROBIOLOGY 2021. [DOI: 10.22207/jpam.15.3.67] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Streptomyces are known for their ability to produce various secondary metabolites used in biotechnology, human medicine and agriculture. Understanding of surface properties is very interesting in the control of interfacial phenomena. The objective of this study was to investigate the effect of consistency and composition of growth medium on the physicochemical properties of the surface of Streptomyces strains. To achieve this objective, Six Streptomyces strains belonging to bioprocess and bio-interfaces laboratory are cultivated in two media Bennett (rich) and GBA (minimum). Both media are tested in solid (agar) and liquid (broth) mode. The wettability θw, electron donor character ˠ (-), electron acceptor character ˠ (+) and Surface free energy ΔGiwi are determined using contact angle measurements. On the two solid media Bennett and GBA, Streptomyces strains develop a hydrophobic surface (96.9° <θw<167.9°) with a weak electron donor character (0.3 mJm-2 < (ˠ (-)) <12.14 mJm-2) and a strong electron acceptor character (0.26 mJm-2 < ˠ (+) < 17.8 mJm-2) and a negative surface free energy ((- 11.8 mJm-2) < ΔGiwi < (-110 mJm-2)). Whereas on both Bennett and GBA liquid media, the surfaces of Streptomyces strains are generally hydrophilic (1.3° < θw < 9.33°) with a strong electron donor character (13.76 mJm-2 < ( ˠ (-)) < 70.06 mJm-2) and a positive surface free energy. By changing the composition of the culture medium, only a slight change in the degree of hydrophobicity and surface free energy of Streptomyces is observed. Regarding the effect of medium composition on the surface properties of Streptomyces, the degree of wettability and the values of surface free energy are no longer the same when the composition of the medium changes. These results could be applied in further studies interested in interfacial phenomena and microbial adhesion in biotechnological fields.
Collapse
|
3
|
Current Understanding on Adhesion and Biofilm Development in Actinobacteria. Int J Microbiol 2021; 2021:6637438. [PMID: 34122552 PMCID: PMC8166509 DOI: 10.1155/2021/6637438] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2020] [Accepted: 05/07/2021] [Indexed: 12/30/2022] Open
Abstract
Biofilm formation and microbial adhesion are two related and complex phenomena. These phenomena are known to play an important role in microbial life and various functions with positive and negative aspects. Actinobacteria have wide distribution in aquatic and terrestrial ecosystems. This phylum is very large and diverse and contains two important genera Streptomyces and Mycobacteria. The genus Streptomyces is the most biotechnologically important, while the genus Mycobacteria contains the pathogenic species of Mycobacteriaceae. According to the literature, the majority of studies carried out on actinomycetes are focused on the detection of new molecules. Despite the well-known diversity and metabolic activities, less attention has been paid to this phylum. Research on adhesion and biofilm formation is not well developed. In the present review, an attempt has been made to review the literature available on the different aspects on biofilm formation and adhesion of Actinobacteria. We focus especially on the genus Streptomyces. Furthermore, a brief overview about the molecules and structures involved in the adhesion phenomenon in the most relevant genus is summarized. We mention the mechanisms of quorum sensing and quorum quenching because of their direct association with biofilm formation.
Collapse
|
4
|
Dokouhaki M, Hung A, Kasapis S, Gras SL. Hydrophobins and chaplins: Novel bio-surfactants for food dispersions a review. Trends Food Sci Technol 2021. [DOI: 10.1016/j.tifs.2021.03.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
|
5
|
Dokouhaki M, Prime EL, Qiao GG, Kasapis S, Day L, Gras SL. Structural-rheological characteristics of Chaplin E peptide at the air/water interface; a comparison with β-lactoglobulin and β-casein. Int J Biol Macromol 2020; 144:742-750. [PMID: 31837361 DOI: 10.1016/j.ijbiomac.2019.12.075] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Revised: 12/10/2019] [Accepted: 12/10/2019] [Indexed: 11/27/2022]
Abstract
The Chaplin E peptide is a surface-active agent that can adsorb to the air/water interface and form interfacial films that display distinct interfacial properties as a function of pH. The ~2 nm thick homogeneous Chaplin E film formed under acidic conditions contains ordered structures that give a high dilatational elasticity. In contrast, the heterogeneous film formed under basic conditions contained fibrils resulting in a rough ~17 nm thick film with predominantly viscoelastic properties, probably due to the reduced intermolecular interactions. These fibrils were also susceptible to breakage, fragmenting into shorter fibrils, which gave a greater elasticity. The fibrils also lead to a greater shear viscosity compared to the ordered structures aligned within the Chaplin E film at pH 3.0. A higher stability was observed for the foam formed by the Chaplin E compared to the foam formed by β-lactoglobulin, consistent with the greater rheological properties observed for the Chaplin E film at the interface. Our findings suggest that Chaplin E has potential to provide long time stability to dispersions in food, consumer goods or pharmaceutical applications, forming films with greater rheological properties and at least similar thickness to those formed by other surface-active proteins such as β-casein and β-lactoglobulin.
Collapse
Affiliation(s)
- Mina Dokouhaki
- School of Science, RMIT University, Bundoora West Campus, VIC 3083, Australia.
| | - Emma L Prime
- Institute for Frontier Materials, Deakin University, Geelong, VIC 3216, Australia
| | - Greg G Qiao
- The Department of Chemical Engineering, The University of Melbourne, Parkville, VIC 3010, Australia
| | - Stefan Kasapis
- School of Science, RMIT University, Bundoora West Campus, VIC 3083, Australia
| | - Li Day
- AgResearch Ltd., Grasslands Research Centre, Tennent Drive, Palmerston North 4442, New Zealand
| | - Sally L Gras
- The Department of Chemical Engineering, The University of Melbourne, Parkville, VIC 3010, Australia; The Bio21 Molecular Science and Biotechnology Institute and The ARC Dairy Innovation Hub, The University of Melbourne, Parkville, Vic 3010, Australia.
| |
Collapse
|
6
|
Dokouhaki M, Hung A, Prime EL, Qiao GG, Day L, Gras SL. pH-Induced interfacial properties of Chaplin E from Streptomyces coelicolor. Colloids Surf B Biointerfaces 2017; 160:589-597. [PMID: 29028607 DOI: 10.1016/j.colsurfb.2017.10.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2017] [Revised: 09/14/2017] [Accepted: 10/03/2017] [Indexed: 10/18/2022]
Abstract
Chaplin E, or Chp E, is a surface active peptide secreted by Streptomyces coelicolor that adopts different structures depending on solution pH but the effect of these structures on the interfacial properties of Chp E is not known. In experiments paired with simulations, Chp E was found to display pH-dependent interfacial assembly and surface activity. At pH 3.0, Chp E formed an ordered non-amyloidal interfacial film with high surface activity; while at pH 10.0, Chp E self-assembled into a heterogeneous film containing randomly arranged fibrils at the interface that was less surface active compared to the film formed at pH 3.0. In simulations at pH 10.0, Chp E molecules showed a higher propensity for dimerization within the solution phase, lower rate of adsorption to the interface and tighter inter-molecular associations at the interface, consistent with the lower surface activity and smaller interfacial area coverage per molecule measured at this pH compared to at pH 3.0. A model is presented for the role of Chp E in the developmental differentiation of Streptomyces coelicolor, where Chp E contributes to changes in surface tension at low pH and the formation of fibrils on the surface of aerial hyphae at high pH. Our data also suggest Chp E could be a promising surface active agent with functional activity that can be controlled by pH.
Collapse
Affiliation(s)
- Mina Dokouhaki
- The Melbourne School of Engineering and Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Parkville, VIC 3010, Australia
| | - Andrew Hung
- School of Science, RMIT University, VIC 3001, Australia
| | - Emma L Prime
- Institute for Frontier Materials, Deakin University, Geelong, VIC 3216, Australia; Polymer Science Group, Department of Chemical and Biomolecular Engineering, The University of Melbourne, Parkville, VIC 3010, Australia
| | - Greg G Qiao
- Polymer Science Group, Department of Chemical and Biomolecular Engineering, The University of Melbourne, Parkville, VIC 3010, Australia
| | - Li Day
- AgResearch Ltd, Grasslands Research Centre, Tennent Drive, Palmerston North 4442, New Zealand
| | - Sally L Gras
- The Melbourne School of Engineering and Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Parkville, VIC 3010, Australia; The ARC Dairy Innovation Hub, The University of Melbourne, Parkville, VIC 3010, Australia.
| |
Collapse
|
7
|
Som Chaudhury S, Das Mukhopadhyay C. Functional amyloids: interrelationship with other amyloids and therapeutic assessment to treat neurodegenerative diseases. Int J Neurosci 2017; 128:449-463. [PMID: 29076790 DOI: 10.1080/00207454.2017.1398153] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Affiliation(s)
- Sutapa Som Chaudhury
- Centre for Healthcare Science and Technology, Indian Institute of Engineering Science and Technology, Shibpur, West Bengal, India
| | - Chitrangada Das Mukhopadhyay
- Centre for Healthcare Science and Technology, Indian Institute of Engineering Science and Technology, Shibpur, West Bengal, India
| |
Collapse
|
8
|
Dokouhaki M, Prime EL, Hung A, Qiao GG, Day L, Gras SL. Structure-Dependent Interfacial Properties of Chaplin F from Streptomyces coelicolor. Biomolecules 2017; 7:E68. [PMID: 28925983 PMCID: PMC5618249 DOI: 10.3390/biom7030068] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2017] [Revised: 09/08/2017] [Accepted: 09/12/2017] [Indexed: 12/27/2022] Open
Abstract
Chaplin F (Chp F) is a secreted surface-active peptide involved in the aerial growth of Streptomyces. While Chp E demonstrates a pH-responsive surface activity, the relationship between Chp F structure, function and the effect of solution pH is unknown. Chp F peptides were found to self-assemble into amyloid fibrils at acidic pH (3.0 or the isoelectric point (pI) of 4.2), with ~99% of peptides converted into insoluble fibrils. In contrast, Chp F formed short assemblies containing a mixture of random coil and β-sheet structure at a basic pH of 10.0, where only 40% of the peptides converted to fibrils. The cysteine residues in Chp F did not appear to play a role in fibril assembly. The interfacial properties of Chp F at the air/water interface were altered by the structures adopted at different pH, with Chp F molecules forming a higher surface-active film at pH 10.0 with a lower area per molecule compared to Chp F fibrils at pH 3.0. These data show that the pH responsiveness of Chp F surface activity is the reverse of that observed for Chp E, which could prove useful in potential applications where surface activity is desired over a wide range of solution pH.
Collapse
Affiliation(s)
- Mina Dokouhaki
- Department of Chemical Engineering and The Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Parkville, VIC 3010, Australia.
| | - Emma L Prime
- Institute for Frontier Materials, Deakin University, Geelong, VIC 3216, Australia.
- Polymer Science Group, Department of Chemical Engineering, The University of Melbourne, Parkville, VIC 3010, Australia.
| | - Andrew Hung
- School of Science, RMIT University, Melbourne, VIC 3001, Australia.
| | - Greg G Qiao
- Polymer Science Group, Department of Chemical Engineering, The University of Melbourne, Parkville, VIC 3010, Australia.
| | - Li Day
- AgResearch Ltd, Grasslands Research Centre, Tennent Drive, Palmerston North 4442, New Zealand.
| | - Sally L Gras
- Department of Chemical Engineering and The Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Parkville, VIC 3010, Australia.
- The ARC Dairy Innovation Hub, The University of Melbourne, Parkville, VIC 3010, Australia.
| |
Collapse
|
9
|
Dragoš A, Kovács ÁT, Claessen D. The Role of Functional Amyloids in Multicellular Growth and Development of Gram-Positive Bacteria. Biomolecules 2017; 7:biom7030060. [PMID: 28783117 PMCID: PMC5618241 DOI: 10.3390/biom7030060] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2017] [Revised: 08/01/2017] [Accepted: 08/03/2017] [Indexed: 01/15/2023] Open
Abstract
Amyloid fibrils play pivotal roles in all domains of life. In bacteria, these fibrillar structures are often part of an extracellular matrix that surrounds the producing organism and thereby provides protection to harsh environmental conditions. Here, we discuss the role of amyloid fibrils in the two distant Gram-positive bacteria, Streptomyces coelicolor and Bacillus subtilis. We describe how amyloid fibrils contribute to a multitude of developmental processes in each of these systems, including multicellular growth and community development. Despite this variety of tasks, we know surprisingly little about how their assembly is organized to fulfill all these roles.
Collapse
Affiliation(s)
- Anna Dragoš
- Terrestrial Biofilms Group, Institute of Microbiology, Friedrich Schiller University Jena, 07743 Jena, Germany.
| | - Ákos T Kovács
- Department of Biotechnology and Biomedicine, Technical University of Denmark, 2800 Lyngby, Denmark.
| | - Dennis Claessen
- Institute of Biology, Leiden University, 2333BE Leiden, The Netherlands.
| |
Collapse
|
10
|
The pH-dependent assembly of Chaplin E from Streptomyces coelicolor. J Struct Biol 2017; 198:82-91. [PMID: 28400129 DOI: 10.1016/j.jsb.2017.04.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2016] [Revised: 03/06/2017] [Accepted: 04/07/2017] [Indexed: 01/01/2023]
Abstract
Chaplin E, is one of five self-assembling peptides secreted by Streptomyces coelicolor that assist aerial growth by lowering the surface tension of water. Although the surface activity of a mixture of chaplin peptides has observed to depend on pH, it is unclear how the solvent environment (i.e. pH) influences the structure, assembly and subsequent functionality of these individual peptides. In this study, the conformation and fibril forming propensity of the Chaplin E peptide was assessed as a function of pH using a combination of experimental measurements and molecular dynamics simulations. At an acidic pH of 3.0, Chaplin E retained a random coil structure, whereas at the isoelectric point of 6.7 or a basic pH of 10.0, Chaplin E rapidly formed amyloid fibrils rich in β-sheet structure with high efficiency (>93%). Molecular dynamics simulations indicate the persistence of greater α-helical content at the N-terminus at high pH; this is likely partly due to the lack of electrostatic repulsion between residues His6 and Lys10. Since fibril formation was observed at high but not at low pH, we propose that the presence of an N-terminal α-helix in the monomeric form of Chaplin E is required for aggregation and conversion to β-amyloid fibrils. The pH sensitivity of Chaplin E peptide structure provides a route to control peptide assembly and may be important for the physiological function of this peptide, as a surface active agent in the transition from vegetative to aerial growth and could assist Streptomyces coelicolor in response to environmental fluctuations in pH.
Collapse
|
11
|
Sunde M, Pham CLL, Kwan AH. Molecular Characteristics and Biological Functions of Surface-Active and Surfactant Proteins. Annu Rev Biochem 2017; 86:585-608. [PMID: 28125290 DOI: 10.1146/annurev-biochem-061516-044847] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Many critical biological processes take place at hydrophobic:hydrophilic interfaces, and a wide range of organisms produce surface-active proteins and peptides that reduce surface and interfacial tension and mediate growth and development at these boundaries. Microorganisms produce both small lipid-associated peptides and amphipathic proteins that allow growth across water:air boundaries, attachment to surfaces, predation, and improved bioavailability of hydrophobic substrates. Higher-order organisms produce surface-active proteins with a wide variety of functions, including the provision of protective foam environments for vulnerable reproductive stages, evaporative cooling, and gas exchange across airway membranes. In general, the biological functions supported by these diverse polypeptides require them to have an amphipathic nature, and this is achieved by a diverse range of molecular structures, with some proteins undergoing significant conformational change or intermolecular association to generate the structures that are surface active.
Collapse
Affiliation(s)
- Margaret Sunde
- Discipline of Pharmacology, School of Medical Sciences and Australian Institute for Nanoscale Science and Technology, University of Sydney, NSW 2006, Australia; ,
| | - Chi L L Pham
- Discipline of Pharmacology, School of Medical Sciences and Australian Institute for Nanoscale Science and Technology, University of Sydney, NSW 2006, Australia; ,
| | - Ann H Kwan
- School of Life and Environmental Sciences and Australian Institute for Nanoscale Science and Technology, University of Sydney, NSW 2006, Australia;
| |
Collapse
|
12
|
Schor M, Reid JL, MacPhee CE, Stanley-Wall NR. The Diverse Structures and Functions of Surfactant Proteins. Trends Biochem Sci 2016; 41:610-620. [PMID: 27242193 PMCID: PMC4929970 DOI: 10.1016/j.tibs.2016.04.009] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2016] [Revised: 04/25/2016] [Accepted: 04/29/2016] [Indexed: 01/26/2023]
Abstract
Surface tension at liquid–air interfaces is a major barrier that needs to be surmounted by a wide range of organisms; surfactant and interfacially active proteins have evolved for this purpose. Although these proteins are essential for a variety of biological processes, our understanding of how they elicit their function has been limited. However, with the recent determination of high-resolution 3D structures of several examples, we have gained insight into the distinct shapes and mechanisms that have evolved to confer interfacial activity. It is now a matter of harnessing this information, and these systems, for biotechnological purposes. Interfacially active proteins fulfill a wide range of biological functions in organisms ranging from bacteria and fungi to mammals. Their physicochemical properties make interfacially active proteins attractive for biotechnological applications; for example, as coatings on nanodevices or medical implants and as emulsifiers in food and personal-care products. High-resolution 3D structures show that the mechanisms by which interfacially active proteins achieve their function are highly diverse.
Collapse
Affiliation(s)
- Marieke Schor
- School of Physics and Astronomy, University of Edinburgh, Edinburgh, UK
| | - Jack L Reid
- School of Life Sciences, University of Dundee, Dundee, UK
| | - Cait E MacPhee
- School of Physics and Astronomy, University of Edinburgh, Edinburgh, UK.
| | | |
Collapse
|
13
|
Jiang S, Wan Q, Krajcikova D, Tang J, Tzokov SB, Barak I, Bullough PA. Diverse supramolecular structures formed by self-assembling proteins of the Bacillus subtilis spore coat. Mol Microbiol 2015; 97:347-59. [PMID: 25872412 PMCID: PMC4950064 DOI: 10.1111/mmi.13030] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/13/2015] [Indexed: 01/03/2023]
Abstract
Bacterial spores (endospores), such as those of the pathogens Clostridium difficile and Bacillus anthracis, are uniquely stable cell forms, highly resistant to harsh environmental insults. Bacillus subtilis is the best studied spore‐former and we have used it to address the question of how the spore coat is assembled from multiple components to form a robust, protective superstructure. B. subtilis coat proteins (CotY, CotE, CotV and CotW) expressed in Escherichia coli can arrange intracellularly into highly stable macro‐structures through processes of self‐assembly. Using electron microscopy, we demonstrate the capacity of these proteins to generate ordered one‐dimensional fibres, two‐dimensional sheets and three‐dimensional stacks. In one case (CotY), the high degree of order favours strong, cooperative intracellular disulfide cross‐linking. Assemblies of this kind could form exquisitely adapted building blocks for higher‐order assembly across all spore‐formers. These physically robust arrayed units could also have novel applications in nano‐biotechnology processes.
Collapse
Affiliation(s)
- Shuo Jiang
- Krebs Institute for Biomolecular Research, Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield, S10 2TN, UK
| | - Qiang Wan
- Krebs Institute for Biomolecular Research, Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield, S10 2TN, UK
| | - Daniela Krajcikova
- Institute of Molecular Biology, Slovak Academy of Sciences, Dubravska cesta 21, Bratislava, 845 51, Slovakia
| | - Jilin Tang
- State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, 130022, China
| | - Svetomir B Tzokov
- Krebs Institute for Biomolecular Research, Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield, S10 2TN, UK
| | - Imrich Barak
- Institute of Molecular Biology, Slovak Academy of Sciences, Dubravska cesta 21, Bratislava, 845 51, Slovakia
| | - Per A Bullough
- Krebs Institute for Biomolecular Research, Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield, S10 2TN, UK
| |
Collapse
|
14
|
van Dissel D, Claessen D, van Wezel GP. Morphogenesis of Streptomyces in submerged cultures. ADVANCES IN APPLIED MICROBIOLOGY 2014; 89:1-45. [PMID: 25131399 DOI: 10.1016/b978-0-12-800259-9.00001-9] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Members of the genus Streptomyces are mycelial bacteria that undergo a complex multicellular life cycle and propagate via sporulation. Streptomycetes are important industrial microorganisms, as they produce a plethora of medically relevant natural products, including the majority of clinically important antibiotics, as well as a wide range of enzymes with industrial application. While development of Streptomyces in surface-grown cultures is well studied, relatively little is known of the parameters that determine morphogenesis in submerged cultures. Here, growth is characterized by the formation of mycelial networks and pellets. From the perspective of industrial fermentations, such mycelial growth is unattractive, as it is associated with slow growth, heterogeneous cultures, and high viscosity. Here, we review the current insights into the genetic and environmental factors that determine mycelial growth and morphology in liquid-grown cultures. The genetic factors include cell-matrix proteins and extracellular polymers, morphoproteins with specific roles in liquid-culture morphogenesis, with the SsgA-like proteins as well-studied examples, and programmed cell death. Environmental factors refer in particular to those dictated by process engineering, such as growth media and reactor set-up. These insights are then integrated to provide perspectives as to how this knowledge can be applied to improve streptomycetes for industrial applications.
Collapse
Affiliation(s)
- Dino van Dissel
- Molecular Biotechnology, Institute Biology Leiden, Leiden University, Leiden, The Netherlands
| | - Dennis Claessen
- Molecular Biotechnology, Institute Biology Leiden, Leiden University, Leiden, The Netherlands.
| | - Gilles P van Wezel
- Molecular Biotechnology, Institute Biology Leiden, Leiden University, Leiden, The Netherlands.
| |
Collapse
|
15
|
Petrus MLC, Claessen D. Pivotal roles for Streptomyces cell surface polymers in morphological differentiation, attachment and mycelial architecture. Antonie van Leeuwenhoek 2014; 106:127-39. [PMID: 24682579 DOI: 10.1007/s10482-014-0157-9] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2014] [Accepted: 03/12/2014] [Indexed: 01/07/2023]
Abstract
Cells that are part of a multicellular structure are typically embedded in an extracellular matrix, which is produced by the community members. These matrices, the composition of which is highly diverse between different species, are typically composed of large amounts of extracellular polymeric substances, including polysaccharides, proteins, and nucleic acids. The functions of all these matrices are diverse: they provide protection, mechanical stability, mediate adhesion to surfaces, regulate motility, and form a cohesive network in which cells are transiently immobilized. In this review we discuss the role of matrix components produced by streptomycetes during growth, development and attachment. Compared to other bacteria it appears that streptomycetes can form morphologically and functionally distinct matrices using a core set of building blocks.
Collapse
Affiliation(s)
- Marloes L C Petrus
- Molecular Biotechnology, Institute Biology Leiden, Leiden University, Sylviusweg 72, 2300 RA, Leiden, The Netherlands
| | | |
Collapse
|