Maintaining cell envelope integrity and intracellular enzyme stability while alleviating transmembrane mass-transfer limitations is important for sustained γ-aminobutyric acid (GABA) production by whole-cell biocatalysis. We investigated the effects of ethanol on the apparent whole-cell glutamate decarboxylase (GAD) activity of Lactiplantibacillus plantarum SS5 and optimized the corresponding GABA production process. Co-incubation with 6–8
The tumor microenvironment (TME) comprises malignant, stromal, immune, and microbial components. Spatial imaging and molecular profiling have identified intracellular bacteria or bacterial signals in selected tumors, although localization, viability, and functional significance vary across tumor types and experimental settings. Certain tumor-associated bacteria can influence cancer progression and treatment response, motivating strategies for selective microbial intervention. Bacteriophages offer bacterial specificity and opportunities for engineering, but their access to intracellular targets remains a major challenge. This narrative review examines three proposed strategies: lytic elimination of intracellular bacteria, modification of bacterial functions, and bacterial production of therapeutic payloads following phage-mediated delivery. Evidence from mammalian-cell uptake studies, intracellular infection models, and emerging cancer cell-bacterium co-cultures supports individual components of these strategies. However, the complete sequence linking systemic engineered phage delivery, intracellular bacterial clearance, and antitumor immune reprogramming has not been established in orthotopic tumor models or human tumor organoid systems. We therefore present the intracellular scalpel as a testable hypothesis and discuss its potential combinations with established cancer treatments and exploratory adjuvants. Particular attention is given to delivery barriers, evidence limitations, biosafety, and the preclinical measurements required to determine whether intracellular bacterial targeting can improve cancer treatment.
Ethanol production from biomass-derived and gaseous substrates (CO, H2 and CO2) is essential for achieving a carbon-neutral society. The thermophilic acetogen Neomoorella thermoacetica offers notable industrial advantages for converting such diverse feedstocks; however, its physiology and metabolic engineering strategies remain insufficiently understood. Using stoichiometric analysis, we evaluated the metabolic pathways for ethanol production from sugars and gaseous substrates, with particular attention to redox balance and ATP conservation. This analysis suggested that introducing an NADPH-dependent route for reducing acetyl-CoA to ethanol could maintain redox-balanced metabolism under conditions that support sufficient energy generation. Consistent with this prediction, disruption of the major acetate-forming pathway, together with the introduction of heterologous NADPH-dependent reductases, enabled high-selectivity ethanol production (> 90
Phlebia radiata is a white-rot basidiomycete that secretes a repertoire of oxidative enzymes making it a promising organism for the sustainable bio-production of aromatic compounds during lignocellulose-containing cultivation. Here, we investigate the association between wood supplementation and extracellular production of aromatic α-hydroxy acids by P. radiata IBWF 87241 under defined axenic conditions, while accompanying changes in extracellular oxidative enzyme activity and residual wood fibres were characterized using enzyme assays and ATR-FTIR spectroscopy. GC–EI–MS analysis of culture filtrate extracts, confirmed by authentic standards, revealed two aromatic α-hydroxy acids produced exclusively under wood-containing conditions. Mandelic acid and 3-phenyllactic acid were produced by P. radiata in ½ soy medium supplemented with 1
Microbial exopolysaccharides (EPSs) have attracted considerable attention as sustainable biopolymers for applications in the food, pharmaceutical, cosmetic and environmental sectors. Halophilic bacteria of the genus Halomonas are emerging as attractive industrial production hosts because their ability to grow under saline conditions reduces contamination risks and may enable cost-effective, low-sterility bioprocesses. However, relatively few EPS-producing Halomonas strains have been comprehensively characterized by integrating physiological, genomic and structural analyses. In this study, an EPS-producing halophilic bacterium, designated Halomonas elongata N1T, was isolated from the hypersaline Salt Lake of Yerevan, Armenia, and evaluated as a potential microbial cell factory for sustainable EPS production. Phylogenomic analyses confirmed its affiliation with H. elongata, showing 98.9
