Article
Biochemical Research Methods
Netsanet Gizaw Assefa, Hilde Hansen, Bjorn Altermark
Summary: Polyhydroxyalkanoates (PHAs) are natural biodegradable polyesters produced by microorganisms. This study identified and characterized a unique PHA biosynthesis enzyme, PhaC (BrPhaC), from a marine bacterium. Unlike other enzymes, BrPhaC is a trimeric enzyme without a lag phase and initiates enzymatic reaction instantly, regardless of temperature.
Article
Biochemistry & Molecular Biology
Yujie Liu, Wanwan Zhao, Siqi Wang, Kaiyue Huo, Yaping Chen, Hongfu Guo, Shufang Wang, Ruihua Liu, Chao Yang
Summary: This study isolated SCL-co-MCL PHA from the halophilic bacterium H. cupida J9 and demonstrated the importance of the low-substrate-specificity PhaCJ9 in PHA polymerization. Docking simulation and site-specific mutagenesis revealed the interaction mechanism between PhaCJ9 and substrates. The results suggest that H. cupida J9 holds promise as a prospective strain for low-cost production of SCL-co-MCL PHA.
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
(2022)
Article
Environmental Sciences
Baotong Zhu, Na Wei
Summary: In this study, a novel biocatalyst was created using synthetic biology techniques for the effective degradation and detoxification of bisphenol compounds. The biocatalyst showed high reusability and stability when immobilized on polyhydroxyalkanoate (PHA) biopolymer beads. This study provides a promising approach for the development of sustainable water reclamation.
ENVIRONMENT INTERNATIONAL
(2022)
Article
Biochemistry & Molecular Biology
Hui Lim, Jo-Ann Chuah, Min Fey Chek, Hua Tiang Tan, Toshio Hakoshima, Kumar Sudesh
Summary: The study demonstrated the importance of both the N- and C-termini of PhaC1(As) in regulating intracellular granule morphology, activity, substrate specificity, dimerization, and stability of the synthase.
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
(2021)
Article
Microbiology
Saki Goto, Yuki Miyahara, Seiichi Taguchi, Takeharu Tsuge, Ayaka Hiroe
Summary: In this study, the coexpression of molecular chaperones and a PHA synthase derived from Bacillus cereus YB-4 was examined to construct an efficient system for 3HBO production. Coexpression of the chaperones promoted the enzyme activity of PHA synthase and increased 3HBO production. This study highlights the valuable approach of utilizing chaperone proteins to enhance the formation of active PHA synthase and the productivity of 3HBO.
Article
Biotechnology & Applied Microbiology
Chung-Hsien Liu, Houng-Yung Chen, Yuh-Ling Lee Chen, Der-Shyan Sheu
Summary: Pseudomonas sp. H9 is an environmental strain isolated from a riverbank soil sample in southern Taiwan, capable of producing novel polyhydroxyalkanoates (PHA) including hybrid PHA and MCL-PHA. The novel PHA synthase, PhaC1(H9), in this strain exhibits broad substrate specificity and plays a key role in the synthesis of hybrid PHA.
ENZYME AND MICROBIAL TECHNOLOGY
(2021)
Article
Polymer Science
Hua Tiang Tan, Min Fey Chek, Soon Zher Neoh, Shaik Ling Ang, Shosuke Yoshida, Toshio Hakoshima, Kumar Sudesh
Summary: I. sakaiensis is a bacterium capable of degrading PET and synthesizing environmentally friendly PHA. This study characterized the PHA synthase gene of I. sakaiensis and demonstrated its ability to produce high levels of PHA in Cupriavidus necator PHB-4. Furthermore, the PhaCIs enzyme can polymerize multiple types of monomers, providing basic information for metabolic engineering of I. sakaiensis to produce different types of PHA from PET.
POLYMER DEGRADATION AND STABILITY
(2022)
Article
Polymer Science
Pei-Shze Mok, Jo-Ann Chuah, Nazalan Najimudin, Pauline-Woan-Ying Liew, Bor-Chyan Jong, Kumar Sudesh
Summary: The study revealed that the S-layer is the key factor affecting PHA biosynthesis by Azotobacter vinelandii. The PhaC of A. vinelandii shows specificity for short-chain-length PHA monomers and has the ability to polymerize 4HB, accumulating 4HB fractions in PHA.
Article
Biotechnology & Applied Microbiology
Ken Harada, Shingo Kobayashi, Kanji Oshima, Shinichi Yoshida, Takeharu Tsuge, Shunsuke Sato
Summary: In this study, the PhaC(Ac) enzyme was engineered to increase the 3HHx fraction in biosynthesized PHA. By targeting specific residues based on three-dimensional structural information, a triple mutant with increased 3HHx fraction was successfully engineered for the biosynthesis of a higher 3HHx-fraction polymer.
FRONTIERS IN BIOENGINEERING AND BIOTECHNOLOGY
(2021)
Article
Microbiology
Athraa Alsaadi, Sree Selva Kumar Ganesen, Tan Suet May Amelia, Radwa Moanis, Eveline Peeters, Sevakumaran Vigneswari, Kesaven Bhubalan
Summary: Researchers have isolated and identified PHA-producing strains from sponge and sediment samples using cultivation and non-cultivation approaches. It was found that one strain showed previously unreported PHA-producing ability, and another strain showed the ability to synthesize 3-hydroxybutyrate without precursor addition.
Article
Agricultural Engineering
Federico Cerrone, Binbin Zhou, Agathe Mouren, Luc Averous, Stephen Conroy, Jeremy C. Simpson, Kevin E. O'Connor, Tanja Narancic
Summary: Polyhydroxyalkanoates (PHAs) are considered as a potential replacement for petrochemical plastics. This study demonstrates that a metabolically versatile Pseudomonas umsongensis can synthesize a blend of short chain length (scl) and medium chain length (mcl)-PHA. The resulting blend exhibits specific physical and mechanical properties.
BIORESOURCE TECHNOLOGY
(2023)
Article
Engineering, Environmental
Ruizhe Pei, Gerard Vicente-Venegas, Agnieszka Tomaszewska-Porada, Mark C. M. Van Loosdrecht, Robbert Kleerebezem, Alan Werker
Summary: Polyhydroxyalkanoates (PHAs) can be produced from municipal waste activated sludge, but their distribution within microbial communities is limited. A selective staining method was developed to visualize the distribution of PHA storage activity and revealed that only a small fraction of the biomass was engaged in PHA accumulation. Optimized staining methods provided high acuity for imaging of PHA distribution and allowed for the distinction of different morphotypes within the biomass. These findings have important implications for PHA recovery methods and provide valuable insights for improving activated sludge processes.
ENVIRONMENTAL SCIENCE & TECHNOLOGY
(2023)
Review
Biochemistry & Molecular Biology
Bibi Nausheen Jaffur, Gopalakrishnan Kumar, Pratima Jeetah, Seeram Ramakrishna, Shashi Kant Bhatia
Summary: The current processes for producing PHAs are costly, but recent advances in functionalizing PHAs from waste streams offer opportunities for fostering a circular economy and waste reduction. This study focuses on developing sustainable and efficient methods, such as bioprocess engineering, catalysts, and materials science.
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
(2023)
Article
Microbiology
Maria-Tsampika Manoli, Juan Nogales, Auxiliadora Prieto
Summary: Polyhydroxyalkanoates (PHAs) are polyesters produced by microorganisms for energy and carbon storage. The synthesis and degradation of PHAs drive a dynamic cycle linked to central carbon metabolism, modulating various bacterial processes. In this study, the role of the PHA cycle in conferring robustness to P. putida was analyzed. The activity of the PHA cycle was shown to control carbon metabolism and cellular mechanisms, enabling stress tolerance and potential biotechnological applications.
Article
Microbiology
Maria-Tsampika Manoli, Juan Nogales, Auxiliadora Prieto
Summary: The study investigates the role of the PHA cycle in conferring robustness to the model bacterium P. putida KT2440. Results demonstrate that modulating the activity of the PHA cycle allows control over the carbon metabolism of P. putida, which in turn can tailor cellular mechanisms and have potential biotechnological applications.
Review
Biochemistry & Molecular Biology
Majela Gonzalez-Miro, Shuxiong Chen, Zennia Jean Gonzaga, Benjamin Evert, David Wibowo, Bernd H. A. Rehm
Article
Chemistry, Multidisciplinary
Kampachiro Ogura, Bernd H. A. Rehm
ADVANCED FUNCTIONAL MATERIALS
(2019)
Review
Microbiology
M. Fata Moradali, Bernd H. A. Rehm
NATURE REVIEWS MICROBIOLOGY
(2020)
Article
Nanoscience & Nanotechnology
Narshone Soda, Zennia Jean Gonzaga, Shuxiong Chen, Kevin M. Koo, Nam-Trung Nguyen, Muhammad J. A. Shiddiky, Bernd H. A. Rehm
Summary: Our study focuses on bioengineering Escherichia coli to self-assemble PHB inclusions that codisplay iron-binding peptides and antibody-binding Z domains. These nanobeads can specifically bind cancer biomarkers in complex mixtures, enabling efficient magnetic separation for enhanced electrochemical detection. This research lays the foundation for utilizing superparamagnetic core-shell structures for sensitive and specific detection of cancer biomarkers, demonstrating the potential of engineering advanced nanomaterials for diverse diagnostic applications.
ACS APPLIED MATERIALS & INTERFACES
(2021)
Article
Chemistry, Multidisciplinary
Shuxiong Chen, Diana H. Quan, Xiaonan T. Wang, Sarah Sandford, Joanna R. Kirman, Warwick J. Britton, Bernd H. A. Rehm
Summary: Current tuberculosis vaccines do not consistently protect against the disease, prompting the need for new and improved vaccines. Research has shown that mycobacterial antigen fusions assembled into particulate vaccines can induce long-lasting antigen-specific T cell responses and protective immunity in mice challenged with virulent Mycobacterium tuberculosis. This study demonstrated that polyester nanoparticles displaying the mycobacterial antigen fusion H4 can offer a level of protection in the lungs comparable to the currently approved TB vaccine, making it a promising subunit vaccine candidate for cost-effective manufacturing and efficient protection against TB.
Article
Immunology
Zennia Jean C. Gonzaga, Christina Merakou, Antonio DiGiandomenico, Gregory P. Priebe, Bernd H. A. Rehm
Summary: The study shows that using PHA inclusions and associated host-cell proteins as a vaccine platform can induce immune responses and prevent P. aeruginosa infection effectively.
Article
Immunology
Benjamin J. Evert, Shuxiong Chen, Robyn McConville, Ryan W. J. Steel, Julie Healer, Justin A. Boddey, Lucas Huntimer, Bernd H. A. Rehm
Summary: A malaria vaccine based on biopolymer particles coated with specific B- and T-cell epitopes was developed, showing enhanced immunogenicity compared to soluble peptide epitopes. The study demonstrated the utility of biologically self-assembled epitope-coated particles as a carrier for next-generation malaria vaccines.
Article
Chemistry, Medicinal
Zennia Jean C. Gonzaga, Jinyong Zhang, Bernd H. A. Rehm
Summary: This study demonstrates that vaccination with biopolymer particles coated with Pseudomonas aeruginosa antigens can induce protective immune responses against P. aeruginosa infections. The vaccine candidate BP-10Ag(2x) showed the best performance and even induced protective immunity in the absence of Alhydrogel adjuvant.
ACS INFECTIOUS DISEASES
(2022)
Article
Nanoscience & Nanotechnology
Donna McNeale, Lygie Esquirol, Shoko Okada, Shai Strampel, Noor Dashti, Bernd Rehm, Trevor Douglas, Claudia Vickers, Frank Sainsbury
Summary: This study demonstrates a tunable strategy for controlling the co-encapsulation ratio of P22 cargo proteins inside cells, verified by FRET with fluorescent protein cargo. This strategy was applied to a two-enzyme reaction cascade, where the loading density of enzymes was found to influence their activity. Molecular crowding was found to affect enzyme activity, with higher activity observed at lower loading density. In addition, increasing the loading density of the rate-limiting enzyme can increase overall activity. This work highlights the importance of controlling enzyme stoichiometry in the design of nanoscale biocatalytic compartments based on P22.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Chemistry, Multidisciplinary
Gayathri Sam, Shuxiong Chen, Karren Plain, Ian Marsh, Mark E. Westman, John Stenos, Stephen R. Graves, Bernd H. A. Rehm
Summary: A stable and nonreactogenic Q fever vaccine is developed by using self-assembled particles incorporating Q fever antigens. The vaccine shows promising immunogenicity and safety in mice and guinea pigs, indicating its potential for further development as a safe and effective subunit vaccine against Q fever.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Article
Immunology
Shuxiong Chen, Victoria Ozberk, Gayathri Sam, Zennia Jean C. Gonzaga, Ainslie Calcutt, Manisha Pandey, Michael F. Good, Bernd H. A. Rehm
Summary: In this study, biopolymer particles (BPs) displaying Strep A vaccine candidate peptides p*17 and K4S2 were successfully assembled in one step inside an engineered E. coli strain. The purified BPs showed a spherical core-shell structure with a biopolymer core and peptide shell. When formulated with aluminum hydroxide, the BPs exhibited desirable properties as a potential Strep A vaccine, including stability, immunogenicity, and protection in an animal model of infection.
Review
Immunology
Gayathri Sam, John Stenos, Stephen R. Graves, Bernd H. A. Rehm
Summary: Q fever is an infectious zoonotic disease caused by Coxiella burnetii, transmitted from livestock to humans via inhalation of the Small Cell Variant. The current Q-VAX vaccine has limitations due to pre-existing sensitivities, and efforts to develop a universal Q fever vaccine have been unsuccessful. Understanding the mechanisms of reactogenic responses is crucial for the development of a safe vaccine.
Article
Biochemical Research Methods
Van T. Dau, Tung T. Bui, Canh-Dung Tran, Thanh Viet Nguyen, Tuan-Khoa Nguyen, Toan Dinh, Hoang-Phuong Phan, David Wibowo, Bernd H. A. Rehm, Hang Thu Ta, Nam-Trung Nguyen, Dzung Dao
Summary: Electrohydrodynamic atomization is a promising approach for respiratory treatment, involving the generation and delivery of micro/nanoparticles as carriers for drugs and antigens. The proposed design in this work utilizes dual electrospray and ionic wind at chamfered tips to simultaneously generate and deliver charged reduced particles, which shows potential for pulmonary nano-medicine delivery with simple device design and manufacturing.
Article
Nanoscience & Nanotechnology
Ben Evert, Ben Vezina, Bernd H. A. Rehm
ACS APPLIED BIO MATERIALS
(2020)
Review
Materials Science, Biomaterials
Narshone Soda, Bernd H. A. Rehm, Prashant Sonar, Nam-Trung Nguyen, Muhammad J. A. Shiddiky
JOURNAL OF MATERIALS CHEMISTRY B
(2019)