bims-livmat 2025-09-14 papers

J Microbiol Biotechnol. 2025 Sep 05. 35 e2507031

A Safe and Versatile Minicell Platform Derived from Lactiplantibacillus plantarum for Biotechnological Applications.

Junhyeon Park, Seungjune Chang, Heymin Kang, SangKu Yi, In-Hwan Jang, Kyung-Ah Lee, Donghyun Kim, Juhyun Kim.

Bacterial minicells are small and chromosome-free cells that result from aberrant cell division and represent a safe alternative to live microbial applications. However, most research on minicells has focused on Escherichia coli, with few studies exploring their development in non-model, biocompatible hosts. In this study, we engineered a minD-deficient Lactiplantibacillus plantarum (formerly Lactobacillus arabinosus and Lactobacillus plantarum) strain capable of producing minicells and systematically evaluated its potential as a chassis for biotechnological applications. Unlike E. coli-based systems, L. plantarum minicells exhibited stable accumulation of heterologous proteins and efficient surface antigen display without evidence of selective export or stress-induced release of toxic compounds. This behavior enabled uniform protein loading and consistent antigen presentation. Additionally, the minicells retained the immunostimulatory properties of their parent cells, underscoring their potential use as adjuvants per se. To improve production efficiency, we employed a continuous cultivation system with controlled growth conditions, which enabled steady-state operation and significantly enhanced minicell yield at optimal dilution rates. Collectively, these findings establish L. plantarum-derived minicells as a safe, robust, and genetically tunable platform suitable for therapeutic delivery, vaccine development, and immunoengineering.

Keywords: Lactiplantibacillus plantarum; Minicell; adjuvant; chemostat; engineered bacteria

DOI: https://doi.org/10.4014/jmb.2503.07031

Food Chem. 2025 Sep 08. pii: S0308-8146(25)03580-0. [Epub ahead of print]495(Pt 1): 146328

Encapsulation of Lactiplantibacillus plantarum subsp. plantarum in oil-phase gels O/W high internal phase emulsions: Improvement of storage stability and gastrointestinal viability.

Enjing Huang, Ziling Li, Fangyuan Zhou, Qinyu Chen, Jiayong He, Xiangyuan Xiong, Youfa Xie, Hongxia Gao, Liqiang Zou.

Probiotics offer health benefits but often lose viability during processing and digestion, hindering their use. Therefore, we developed oil-phase gel O/W high internal phase emulsions (HIPEs) by incorporating beeswax to encapsulate Lactiplantibacillus plantarum subsp. Plantarum (L. plantarum). The incorporation of 1% and 2% beeswax reduced droplet size while improving the physical stability and strengthening the gel structure of the HIPEs. Crucially, incorporating beeswax markedly improved the retention of L. plantarum within the HIPEs oil phase. In addition, the oil-phase gelled HIPEs enhanced the thermal resistance of L. plantarum at 72 °C and 65 °C. It also imparted storage stability, which was 7.42 log10 CFU/g with 1% beeswax for 30 days storage at 4 °C. The addition of beeswax to the oil phase of HIPEs minimized L. plantarum's viability loss in the gastrointestinal tract. This study contributes to the development of a probiotic emulsion encapsulation system that reaches the colon with high viability.

Keywords: Gastrointestinal viability; Heat resistance; Lactiplantibacillus plantarum subsp. Plantarum; Oil-phase gel HIPEs; Storage stability

DOI: https://doi.org/10.1016/j.foodchem.2025.146328

PNAS Nexus. 2025 Sep;4(9): pgaf268

Microbial living materials promote coral larval settlement.

R3D Consortium

The global decline of coral reefs calls for new strategies to rapidly restock coral populations and maintain ecosystem functions and services. Low recruitment success on degraded reefs hampers coral sexual propagation and leads to reduced genetic diversity and impaired reef resilience. Here, we introduce a Bacterial Reef Ink (Brink) to assist in coral larval settlement. Brink is a photopolymerized living material that can be rapidly applied to restoration substrates and has been formulated to cultivate two settlement-inducing bacterial strains (Cellulophaga lytica and Thalassotalea euphylliae). Settlement assays performed with broadcast spawning (Montipora capitata) and brooding (Pocillopora acuta) Indo-Pacific corals showed that Brink-coated substrates increased settlement >5-fold compared with uncoated control substrates. Brink can be applied as a flat coating or patterned using light-assisted 3D bioprinting, enabling diverse applications in reef restoration and engineering. This approach demonstrates the potential of functional living materials to enhance coral ecosystem engineering and support coral reef rehabilitation.

Keywords: bacteria; bioprinting; coral recruitment; coral reef restoration; ecosystem engineering

DOI: https://doi.org/10.1093/pnasnexus/pgaf268