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PubMed2025

A comprehensive analysis of supermere, exomere, and extracellular vesicle isolation and cargo in colorectal cancer.

Biofluids contain a heterogeneous mixture of extracellular vesicles and non-vesicular nanoparticles (including exomeres and supermeres) that transport a diverse array of proteins, RNA, and lipids. Our previous efforts to characterize the contents of these carriers in colorectal cancer relied on 2D culture systems requiring large-scale setups and time-consuming ultracentrifugation-based isolation. To streamline this process, we have combined 3D hollow-fiber bioreactor production and fast-protein liquid chromatography-based size-exclusion chromatography. Here, we compare the impact of culture methods and purification strategies on small extracellular vesicle, exomere, and supermere cargo. Proteomic analyses show consistently distinct profiles for extracellular vesicles, exomeres, and supermeres regardless of culture conditions or isolation method. In contrast, these two variables influence small RNAs, their base modifications, and lipidomic profiles. We present an online tool to query these and future secretome datasets (https://superomics.shinyapps.io/browse).

Humans↗

PubMed2026

Reprogrammed Komagataella phaffii for enhanced secretory expression of human lactoferrin.

Human lactoferrin (hLF) is a multifunctional glycoprotein of the transferrin family derived from milk and mucosal secretions, which exhibits antibacterial, anti-tumor, and immunomodulatory functions, and is an important component of infant formula. Conventional methods for lactoferrin expression are often inefficient, primarily due to inadequate protein synthesis capabilities and poor stability within microbial hosts. Herein, a Komagataella phaffii yeast strain capable of high-level secretory expression of hLF was constructed by reprogramming the endoplasmic reticulum (ER) and vacuole using CRISPR/Cas9 technology. A dual-expression cassette containing the AOX1 promoter, an α-secretion signal peptide, the hLF gene, and a terminator was integrated into three different sites of the K. phaffii genome. The stepwise strategy combining expansion of the ER membrane involved in protein synthesis with knockout of vacuolar proteases further enhanced hLF production. Subsequently, 0.1 g/L FeCl₃ was added to the medium to reduce the toxicity of hLF and improve its stability. After high-density cultivation of K. phaffii through optimization of cultivation conditions in shake flasks and a 5 L bioreactor, the secretory intact hLF titer reached 2214 mg/L, representing a 76.3-fold increase achieved through these engineering strategies. In addition, antibacterial experiments demonstrated that this secretory hLF had a significant inhibitory effect on Escherichia coli, Staphylococcus aureus, and yeast. Overall, the developed K. phaffii protein expression platform enabled efficient production of lactoferrin, demonstrating its potential for expressing other lactoproteins.

Lactoferrin↗

PubMed2025

Unveiling the genetic basis of the low pH response in the acidophilic yeast Maudiozyma bulderi as a potential host for biorefinery.

Nonconventional yeasts represent a great genetic and phenotypic diversity with potential for industrial strain development in the bio-production of green chemicals. In recent years, mass genome sequencing of nonconventional yeasts has opened avenues to improved understanding of transcriptional networks and phenotypic plasticity and gene function, including the discovery of novel genes. Here, we investigated the expressional and morphological changes at low-pH in three strains of the acidophilic yeast Maudiozyma bulderi (previously Kazachstania bulderi and Saccharomyces bulderi): CBS 8638, CBS 8639, and NRRL Y-27205. The comparison of the transcriptome of cells growing in a bioreactor at pH = 5.5 vs pH = 2.5, primarily showed dysregulation of genes involved in cell wall integrity, with NRRL Y-27205 the least acidophilic strain, showing the largest transcriptional response when compared to the other strains. We identified four uncharacterized genes, unique to M. bulderi, and predicted function as transporters, upregulated at low pH. Microscopy studies showed that M. bulderi cell wall is not damaged in acidic environment, and the membrane lipid composition remains stable at low pH, unlike Saccharomyces cerevisiae. Overall, our data on transcriptional variability in M. bulderi highlights genes and cellular pathways involved in the acidophilic adaptation of this species and can aid further strain development.

Hydrogen-Ion Concentration↗

PubMed2026

Characterisation of metabolic burden in Pseudomonas putida reveals precursor limitation in heterologous lycopene production.

BACKGROUND: The introduction of heterologous pathways into microbial hosts often imposes a metabolic burden on the cell, arising from three major physiological constraint layers: competition for gene expression resources, limited precursor availability and flux distribution, and insufficient energy and redox supply. Although Pseudomonas putida KT2440 is considered a robust and metabolically versatile production host, it remains unclear which of these constraint layers primarily limits heterologous terpenoid production in this organism. Here, lycopene biosynthesis was used as a model system to systematically dissect these three potential sources of metabolic burden. RESULTS: A capacity-monitoring system revealed no clear reduction in transcriptional or translational capacity across the tested strains and cultivation conditions, indicating that general gene expression capacity was not the primary limiting factor. Instead, lycopene production depended strongly on promoter architecture and plasmid backbone, showing that regulatory design shaped pathway performance. Enhancing precursor supply by introducing a heterologous mevalonate (MVA) pathway substantially increased product titres, identifying precursor availability from the native MEP pathway as the dominant bottleneck. This conclusion was independently supported by exogenous mevalonate supplementation, which further increased lycopene accumulation but also revealed saturation at higher concentrations, suggesting that downstream pathway balance or enzyme capacity became limiting once precursor supply was relieved. Under controlled bioreactor conditions, lycopene titres increased from approximately 1 mg/L to nearly 25 mg/L, indicating that process conditions further modulate production performance, suggesting an additional contribution of process-dependent energy and redox constraints. CONCLUSION: Metabolic burden during heterologous lycopene production in P. putida is governed primarily by precursor availability rather than by limitations in general gene expression capacity. Regulatory properties of the vector system strongly influence pathway performance, while controlled cultivation conditions can further improve production by alleviating additional process-dependent constraints. Together, these findings provide a systematic framework for distinguishing constraint layers and guiding the optimisation of heterologous terpenoid production systems.

Lycopene↗

PubMed1977

The tubular loop fermentor: oxygen transfer, growth kinetics, and design.

Oxygen transfer measurements using a dynamic method and evaluated with an appropriate mathematical model have been made on a tubular loop bioreactor, Correlations of the type used in tank systmes are used to describe the influence of power and aeration rate on the mass transfer coefficient. Yeast cultures grown on hydrocarbon and glucose substrates show growth characteristics similar to conventional tank results. Model considerations for large-scale tubular fermentors allow for the prediction of the steady-state oxygen profiles and maximum reactor length. Combination with two-phases flow and oxygen transfer correlations yields a design procedure for commercial scale tubular loop fermentors.

Absorption↗

PubMed1977

Electric field control of lipase membrane activity.

Lipase (EC 3.1.1.3., from Pseudomonas sp.) was entrapped in collagen membrane containing liquid crystal (4-methoxybenzilidene-4'-n-butylaniline). The activity of the lipase-liquid crystal membrane at an applied voltage of 4 V was 3.4 compared to a membrane tested without imposition of an external electric field. A linear relationship was observed between the activity of the lipase-liquid crystal membrane and the current. The apparent Michaelis constant (K'm) of the lipase-liquid crystal membrane under electric field was identical to that of the membrane under ordinary condition. Activation of the lipase-liquid crystal membrane was observed repeatedly, i.e., activation in the presence of an electric field and reversion to a basal level upon removal of the field occurred cyclically. Activity control of immobilized enzymes is desirable for switching devices of a bioreactor. Possible mechanisms of the lipase activation by electric field are discussed.

Collagen↗

PubMed2026

Engineering the Vero Cell Lineage: Toward a Programmable Vaccine Manufacturing Platform.

Vero cells remain an indispensable continuous substrate for human viral vaccine manufacturing. Despite decades of empirical process optimization, intrinsic genomic instability, including segmental aneuploidy and dynamic chromatin rearrangements, continues to limit the durability of engineered phenotypes under sustained viral burden and bioreactor stress. Here, we review the expanding engineering toolkit for the Vero lineage across a three-layered functional framework: the membrane interface, cytoplasmic foundry, and nuclear blueprint, evaluating translational prospects at each level. Receptor transplantation and morphological reprogramming have broadened viral entry range and enabled suspension-adapted culture formats, while metabolic flux management and temporally controlled apoptosis modulation have addressed intracellular production bottlenecks, albeit often with trade-offs between productivity, biosafety, and long-term population stability. At the genomic level, targeted perturbations of transcriptional regulators and emerging epigenetic interventions offer more durable gains, yet expression drift, clonal heterogeneity, and karyotypic instability during extended passaging highlight the need for locus-level precision rather than constitutive trait installation. Looking forward, infection-responsive dynamic logic circuits and the systematic identification of Vero-specific genomic safe harbors could shift the paradigm toward a conditionally responsive manufacturing architecture. Collectively, these advances suggest a pathway for transitioning the Vero lineage from a passive, empirically optimized biological substrate into a conditionally responsive, genomically stable, and programmable platform for modern vaccine preparedness.

Vero cells↗

PubMed1992

Murine soluble Fc gamma receptors/IgG-binding factors (IgG-BF): analysis of the relation to Fc gamma RII and production of milligram quantities of biologically active recombinant IgG-BF.

The production of soluble forms of low-affinity Fc gamma R by cells expressing recombinant or natural membrane Fc gamma RII, and the structural relationships between these soluble receptors and membrane Fc gamma RII are described. We show that 37-40 kD soluble Fc gamma RII, corresponding to the two N-terminal domains of Fc gamma RII and binding to IgG, are spontaneously produced in vitro by cleavage of membrane Fc gamma RII. Moreover, we describe methods to produce and purify to homogeneity large quantities of endotoxin-free recombinant IgG-binding factor (rIgG-BF) from the culture medium of a cell line transfected with a mutated Fc gamma RII cDNA. These methods include the use of bioreactors for culturing transfected fibroblasts and the purification of rIgG-BF by ion-exchange chromatography and hydrophobic-interaction chromatography. By using such procedures, about 2.4 mg of rIgG-BF were purified from 1 liter of culture medium of transfected fibroblasts. Like natural IgG-BF, the 95-99% pure rIgG-BF suppressed, in a dose-dependent manner, secondary in vitro IgG antibody responses to sheep red blood cells.

Amino Acid Sequence↗

PubMed2025

Development of a plant-based vaccine against brucellosis: stable expression of Brucella abortus OMP25 in transgenic tobacco.

Brucellosis, caused by Brucella species, is a global threat to livestock farming, resulting in economic losses and socio-economic challenges, particularly in rural areas. Despite its impact, no licensed human vaccines are available. Animal vaccination remains the most cost-effective control method, but traditional vaccine production is expensive. Edible vaccines, using plants as bioreactors to produce immunogenic antigens, offer a low-cost alternative by eliminating complex purification processes. This study developed a transgenic plant by expressing the Brucella abortus outer membrane protein OMP25 in tobacco plants. OMP25, a conserved transmembrane protein with high immunogenicity, was cloned into a Gateway pDONR vector via a Boundary Pairing reaction and transferred to a binary destination vector via a Left-Right reaction. The destination vector was introduced into Agrobacterium tumefaciens and subsequently used for Agrobacterium-mediated transformation of tobacco plants. Transgenic plants were selected on media containing kanamycin, and the expression of the transgene was verified through the fluorescence of green fluorescent protein. Microcallus formation and shoot development on selective media confirmed kanamycin resistance and the successful integration of the transgene. After phenotypic selection, genomic DNA was extracted from transgenic plants and analyzed by PCR (Polymerase Chain Reaction) using primers specific to the OMP25 gene. Positive PCR results validated the successful integration of the OMP25 gene into the plant genome. Gene expression was further confirmed at the RNA level through real-time quantitative PCR (qRT-PCR) and at the protein level via Western blot analysis. Future studies will evaluate immune responses in animal models. This approach demonstrates the potential for low-cost, effective vaccines to combat brucellosis, addressing critical economic and public health challenges.

Plants, Genetically Modified↗

PubMed2026

Targeted multiplex gene knockouts in Lemna minor using CRISPR/Cas9.

Lemna minor (commonly known as duckweed) is a fast-growing aquatic plant recognized as a promising green bioreactor for recombinant protein production. Its rapid proliferation, high protein yield, environmental adaptability, and edibility make it highly attractive for biotechnological applications. It is essential to develop and expand genetic tools tailored to this species to maximize these advantages and further unlock its biotechnological potential. A key strategy for achieving this goal is the implementation of advanced genome editing technologies, such as the CRISPR/Cas9 system. Although multiplex CRISPR/Cas9 gene editing has previously been successfully applied in Lemna aequinoctialis, the capability of the endogenous plant tRNA processing system for multiplex editing in L. minor using the polycistronic tRNA-sgRNA (PTG)/Cas9 system has not yet been explored. In this study, a PTG construct was engineered to include four sgRNAs designed to simultaneously target two plant-specific glycosyltransferase genes: α-1,3-fucosyltransferase (FucT) and β-1,2-xylosyltransferase (XylT). As anticipated, the PTG-Cas9 system successfully induced frameshift mutations, characterized by insertions and deletions (indels), in regenerated L. minor plants derived from transformed calli. Validation via PCR and RT-PCR analysis, followed by sequencing of the target loci, confirmed the presence of indels at the target sites. Furthermore, western blot analyses utilizing antibodies specific to XylT and FucT in two homozygous lines (lines 44 and 217) revealed truncated XylT proteins in both lines. Moreover, an in-frame FucT protein was detected in line 217, whereas FucT expression was absent in line 44. This study marked the first successful demonstration of PTG-Cas9 system for multiplex genome editing in L. minor, paving the way for advanced genetic engineering in this species.

CRISPR-Cas Systems↗

PubMed2026

In silico analysis of metal resistance genes in Pseudomonas extremaustralis 2E-UNGS: Genomic insights and safety assessment for wastewater biotreatment.

Pseudomonas extremaustralis 2E-UNGS is a non-pathogenic strain isolated from the polluted Reconquista River basin (Buenos Aires Metropolitan Area, Argentina), with a 20-year history of study focused on its survival strategies that have enabled its application in various processes such as waste biotreatment and biosensing. Regarding bacterial-metal interactions, P. extremaustralis 2E-UNGS is capable of biosorbing Cd(II), Zn(II), and Cu(II), and biotransforming Cr(VI) to Cr(III), facilitating both the removal of these metals from aqueous systems and their use in biosensor development. The complete circular chromosome (6,372,594 bp) has been annotated in the NCBI GenBank under accession number NZ_CP091043.1. The aim of this work was to perform an in-depth exploration of the P. extremaustralis 2E-UNGS genome to support the optimization of sustainable bioprocesses within the One Health framework. To this end, the integration of experimental evidence with a detailed in silico analysis of key genes involved in metal-microorganism interactions, antibiotic resistance, and their interconnections provides valuable insights for the optimization of future biotechnological applications. Considering its antibiotic resistance profile, together with the activation of efflux pumps induced by metal stimuli-particularly observed under Zn(II) exposure-P. extremaustralis 2E-UNGS can be regarded as suitable for the design of confined bioreactor processes, minimizing the risk of potential accidental environmental releases. Therefore, modulation of gene expression emerges as a promising approach to enhance the efficiency of metal-loaded wastewater biotreatments.

Pseudomonas↗

PubMed2026

Myeloma engraftment suppresses osteocytic ossification signatures rescued by loading in mice and reveals predictors of patient outcome.

Multiple myeloma (MM) is a malignant plasma cell disease inducing osteolytic lesions by disrupting bone homeostasis, fostering catabolic and suppressing anabolic functions. While the impact on osteoblast generation and function is well documented, alterations of osteocyte function and extracellular matrix (ECM) are not yet fully understood. Thus, using a syngeneic mouse model of MM by injecting MOPC315.BM cells intratibially into BALB/c mice (n = 95), we performed transcriptomic profiling of an osteocyte-enriched population and identified a mechanosensitive matrisomal gene signature, which was disrupted by tumor engraftment. Non-invasive tibial loading restored the expression of 94 ECM-associated genes, including collagens, fibronectin, and aggrecan. Cross-species integration with RNA-seq data from 387 MM patients revealed eight ECM-related genes whose expression correlated with overall survival (VEGFA, BCAN, FGF13, TNFSF8, SDC1, LAMC1, SEMA3A, and CCL2). Four of these genes (Vegfa, Sdc1, Sema3a, Ccl2) were also load-responsive in a murine osteocyte (IDG-SW3 cells) bioreactor model. Our findings indicate that an existing mechanosensitive osteocytic repair program is suppressed by MM cells, which can be reinvigorated via a brief single loading session. It suggests that exercise-based interventions may be beneficial to restore bone mass through endochondral ossification programs in patients with MM.

Bone disease↗

PubMed2026

Systematic modular engineering of genome-integrated Escherichia coli MG1655 for high-level 2'-fucosyllactose production.

2'-Fucosyllactose (2'-FL), the most abundant human milk oligosaccharide (HMO), has attracted considerable interest for its prebiotic and immunomodulatory functions, with broad applications in infant nutrition. In this study, we report the development of a high-yield, genome-integrated 2'-FL-producing strain based on Escherichia coli MG1655 through systematic modular optimization. Starting from a single-copy BKHT strain (MGC06), we first optimized the copy number of the α-1,2-fucosyltransferase (α-1,2-FT) gene BKHT. Subsequently, the GDP-L-fucose supply was enhanced through coordinated genomic integration of the gene clusters cpsG-cpsB and gmd-fcl, while the multidrug efflux transporter gene mdfA was integrated to improve product export and strain robustness. BKHT copy number was then re-evaluated in the optimized background, with four copies yielding the highest production. The final engineered strain, harboring all genetic modifications stably integrated into the chromosome, produced 17.18 g/L 2'-FL in shake-flask culture. In fed-batch fermentation using a 5-L bioreactor, this strain achieved a titer of 154.12 g/L after 60 h, with a productivity of 2.57 g/L/h. Notably, throughout the entire fermentation process, no antibiotics or inducers were supplemented, underscoring the genetic stability and regulatory compliance of this plasmid-free system. To our knowledge, this represents the highest 2'-FL titer reported to date, positioning our engineered strain as a promising candidate for commercial 2'-FL production.

Escherichia coli↗

PubMed2026

Magnetite facilitates phage-bacteria interactions and phage-associated metabolic coordination for medium-chain fatty acid biosynthesis under ammonia stress.

Medium-chain fatty acid (MCFA) production from waste activated sludge (WAS) is considered to rely on the syntrophic interactions among distinct functional microorganisms. Whether phages represent an overlooked ecological component involved in MCFA biosynthesis remains unclear. MCFA production is often inhibited by high total ammonia nitrogen (TAN). Conductive materials have been proposed as effective strategies to enhance or recover MCFA production under TAN stress. Therefore, the inhibition-recovery system could provide a useful framework for investigating whether viral ecological responses are associated with MCFA-related metabolic processes. In this study, magnetite (Fe3O4) was selected as the recovery strategy of MCFA production under TAN stress. Results showed that a total of 3915 vOTUs and 118 metagenome-assembled genomes were recovered from the anaerobic bioreactors subjected to three conditions: Control (without TAN stress), TAN stress, and TAN stress with Fe3O4 presence. Under high TAN environment (∼5 g/L), MCFA production reduced by 49% (1.3 g COD/L) in comparison to that without high TAN stress. The ecological coupling between temperate phages and MCFA-related bacterial hosts was weakened, accompanied by substantial decreases in the abundance and transcriptional abundance of phage-associated auxiliary metabolic genes (AMGs) related to MCFA synthesis (e.g., fatty acid biosynthesis, acyl-chain metabolism). In the presence of Fe3O4 (i.e., 10 g/L), MCFA production was four and two times higher than those with and without high TAN stress. In addition to enhanced phage-bacteria ecological coupling and increased the abundance and transcription of AMGs related to MCFA formation, Fe3O4 increased the abundance and expressions of electron-transfer-related AMGs (e.g., cbb3-type cytochrome c oxidase, type IV pilus assembly genes) and QS-related LuxR-family and HTH-type regulators, indicating that such indirect pathway could be largely overlooked during MCFA synthesis. This is also the first-time reporting that phages could represent an ecological layer responsive to iron oxide. Analyses of publicly available metagenomes collected from MCFA-oriented anaerobic systems further confirmed that phages could be broadly associated with the metabolic processes involved in MCFA biosynthesis. Taken together, this study reveals that phages could serve as an overlooked ecological layer associated with MCFA metabolism and provide a viral-ecology perspective for understanding TAN inhibition and iron oxide-mediated recovery during WAS-to-MCFA bioconversion.

Ammonia inhibition↗

PubMed2026

Inducible flocculation in Komagataella phaffii enables enhanced biomass separation for biopharmaceutical production.

Biomass separation represents a critical bottleneck in Komagataella phaffii-based biopharmaceutical processes, as typically high cell densities of 40 - 50 % create significant operational, technical and economic challenges for harvest operations. Yeast cell aggregation (flocculation) provides a solution to accelerate cell sedimentation by increasing particle size, thus allowing to improve biomass-supernatant separation efficiency during both natural gravity settling and (continuous) centrifugation operations. This study demonstrates successful engineering of K. phaffii strains with an inducible flocculation phenotype using CRISPR/Cas9-based genome editing to integrate the Saccharomyces cerevisiae FLO1 (ScFLO1) gene under control of various regulatory elements, including methanol-inducible and derepressible promoters. Flocculation strength could be enhanced by implementing transcriptional positive feedback circuits based on the methanol-inducible AOX1 promoter. To address methanol-free production requirements, we developed alternative systems to retrofit PAOX1-based ScFLO1 expression and exploited the derepressible PDF promoter, offering broader compatibility with biopharmaceutical manufacturing facilities. Flocculating cells cultivated in a bioreactor demonstrated significantly improved sedimentation behavior, with considerably lower supernatant turbidity after short low-speed centrifugation or gravity sedimentation compared to non-flocculating controls. Crucially, cell flocculation had no negative impact on product amount and quality when expressing a multivalent NANOBODY® VHH molecule with pharmaceutical relevance. Thus, this work establishes the first genetically engineered flocculation system in K. phaffii compatible with recombinant protein production, providing the basis for an innovative approach to streamline harvest operations in biopharmaceutical processes.

Flocculation↗

PubMed2026

High-level terpene production via a novel Actinomycetota-derived MVA pathway in E. coli.

The heterologous production of terpene in microbial hosts is often limited by inefficient and unstable pathway expression, creating a major bottleneck for industrial-scale synthesis. While E. coli as a chassis offers significant advantages, such as rapid growth, ease of cultivation, and genetic tractability. Its endogenous supply of terpenoid precursors remains a critical constraint, fundamentally restricting high-yield production. To address this challenge, we developed a genomically integrated Mevalonate (MVA) pathway from Actinomycetota in E. coli BL21(DE3) to enhance terpene precursor supply. Our approach began with an in silico multi-layer global genome mining analysis of 25,261 Actinomycetota genomes to identify a series of MVA pathway enzymes with potentially high catalytic efficiency, created a high-efficiency chassis E. coli MVA platform (ecMVA-1 and ecMVA-2) for terpene precursor synthesis. Its functionality was validated by testing eight distinct TSs. Among them, the fermentation of artemisinin precursor amorphadiene using a 5-liter bioreactor yielded 947.80 mg/L. These results indicated that E. coli (MVA) is well-suited for TS studies in the laboratory as well as holding significant promise for industrial applications. In addition, this in silico approach offers a new perspective for metabolic engineering and provides potential reservoir of diverse chassis for the industrial production of terpenoid-derived compounds.

Actinomycetota↗

PubMed1992

Purification and biochemical characterization of non-myristoylated recombinant pp60c-src kinase.

To obtain sufficient material for the biochemical and biophysical study of pp60c-src, we have utilized a recombinant pp60c-src baculovirus lacking the myristoylation site at codon 2. On infection of Sf9 cells, this virus produced large amounts of soluble non-myristoylated pp60c-src. The use of non-myristoylated pp60c-src (1) increases production of pp60c-src compared with the wild-type protein, (2) facilitates purification, (3) yields a stable product and (4) allows biochemical studies in the absence of detergents. Up to 20 mg of pp60c-src of greater than 95% purity has been purified from 6 litres of Sf9 cells grown in a bioreactor. One major and multiple minor forms of pp60c-src were separated by Mono Q f.p.l.c. Isoelectric focusing of purified pp60c-src species revealed heterogeneity, some of which could be attributed to differences in the tyrosine phosphorylation state of the enzyme. Kinetic analysis of non-myristoylated pp60c-src kinase in the presence of Mg2+ gave Km values for angiotensin II and ATP of 2 mM and 30 microM respectively and a Vmax. of 620 nmol/min per mg. The kinetic constants and metal ion preferences of a number of copolymers and peptide substrates have been compared. Polylysine and poly(GLAT), which was not phosphorylated by the pp60c-src kinase, dramatically activated autophosphorylation of Tyr-416, suggesting a conformation modulation of pp60c-src by charged polymers. This finding implies that Tyr-527 dephosphorylation is not sufficient for full activation of pp60c-src in vitro.

Amino Acid Sequence↗

PubMedDate not supplied

Environmental biotechnology: biotechnology solutions for a global environmental problem, hazardous chemical wastes.

Biotechnology has a growing place in the remediation of hazardous waste sites throughout the world, and especially in Asia where population density is high and land and fresh water are scarce. In-situ bioremediation has been demonstrated already to be highly effective for petroleum hydrocarbons (alkanes, aromatics, polychlorophenols) and organophosphate pesticides in soils and for gasoline by-products (benzene, toluene, xylene) and chlorinated solvents (trichloroethylene) in groundwater. Heavy metals and PCBs are not suitable for bioremediation. Environmental biotechnology includes solid-phase and slurry-phase bioremediation for contaminated soils and site-specific bioreactors for contaminated groundwater. Specific examples are presented. From a policy point of view, accumulated wastes must be detoxified, preferably at sites where they already exist. We cannot continue to rely on their removal and disposal "elsewhere". For current waste streams, we must minimize the volumes and toxicity. Environmental biotechnology will play a key role.

Biotechnology↗