Junhyeon Park, Karen M Polizzi, Jongmin Kim, Juhyun Kim
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引用次数: 0
Abstract
Background: Minicells are chromosome-free derivatives of bacteria formed through irregular cell division. Unlike simplified structures, minicells retain all cellular components of the parent cell except for the chromosome. This feature reduces immunogenic responses, making them advantageous for various biotechnological applications, including chemical production and drug delivery. To effectively utilize minicells, it is essential to ensure the accumulation of target proteins within them, enhancing their efficiency as delivery vehicles.
Results: In this study, we engineered Escherichia coli by deleting the minCD genes, generating minicell-producing strains, and investigated strategies to enhance protein accumulation within the minicells. Comparative proteomic analysis revealed that minicells retain most parent-cell proteins but exhibit an asymmetric proteome distribution, leading to selective protein enrichment. We demonstrated that heterologous proteins, such as GFP and RFP, accumulate more abundantly in minicells than in parent cells, regardless of expression levels. To further enhance this accumulation, we manipulated protein localization by fusing target proteins to polar localization signals. While proteins fused with PtsI and Tsr exhibited 2.6-fold and 2.8-fold increases in accumulation, respectively, fusion with the heterologous PopZ protein resulted in a remarkable 15-fold increase in protein concentration under low induction conditions.
Conclusions: These findings highlight the critical role of spatial protein organization in enhancing the cargo-loading capabilities of minicells. By leveraging polar localization signals, this work provides a robust framework for optimizing minicells as efficient carriers for diverse applications, from therapeutic delivery to industrial biomanufacturing.
期刊介绍:
Biological engineering is an emerging discipline that encompasses engineering theory and practice connected to and derived from the science of biology, just as mechanical engineering and electrical engineering are rooted in physics and chemical engineering in chemistry. Topical areas include, but are not limited to:
Synthetic biology and cellular design
Biomolecular, cellular and tissue engineering
Bioproduction and metabolic engineering
Biosensors
Ecological and environmental engineering
Biological engineering education and the biodesign process
As the official journal of the Institute of Biological Engineering, Journal of Biological Engineering provides a home for the continuum from biological information science, molecules and cells, product formation, wastes and remediation, and educational advances in curriculum content and pedagogy at the undergraduate and graduate-levels.
Manuscripts should explore commonalities with other fields of application by providing some discussion of the broader context of the work and how it connects to other areas within the field.