Metabolic and proteomic mechanism of bisphenol A degradation by Bacillus thuringiensis

Melatonin and resveratrol alleviate molecular and metabolic toxicity induced by Bisphenol A in endometrial organoids

Bisphenol A (BPA), a widespread environmental contaminant, poses concerns due to its disruptive effects on physiological functions of the uterine endometrium. In contrast, melatonin (MT) and Resveratrol (RSV) are under scrutiny for their potential protective roles against BPA-induced damage. For the efficacy and ethical concerns in the animal test, endometrial organoids, three-dimensional models mimicking endometrium, serve as crucial tools for unraveling the impact of environmental factors on reproductive health. This study aimed to comprehensively characterize the morphological, molecular and metabolic responses of porcine endometrial organoids to BPA and assess the potential protective effects of MT and RSV. Porcine uteri were prepared, digested with collagenase, mixed with Matrigel, and incubated at 38°C with 5 % CO2. Passaging involved dissociation through trypsin-EDTA treatment and subculturing. The culture medium was refreshed every 2-3 days. To investigate the environmental impact on reproductive health, endometrial organoids were treated with BPA (0.5 µM), MT (with/without BPA at 0.1 µM), and/or RSV (10 µM). Various molecular screening using gene expression, western blotting, immunofluorescence staining, and metabolites profiling were assessed the effects of BPA, MT, and RSV in terms of cell viability, morphology, reproductivity, and metabolism alteration in the endometrial organoids. As expected, BPA induced structural and molecular disruptions in organoids, affecting cytoskeletal proteins, Wnt/β-catenin signaling, and epithelial/mesenchymal markers. It triggered oxidative stress and apoptotic pathways, altered miRNA expression, and disrupted the endocannabinoid system. The level of glucose, galactose, and essential amino acids were increased or decreased by approximately 1.5-3 times in BPA-treated groups compared to the control groups (p-value < 0.05), indicating metabolic changes. Moreover, MT and RSV treated groups exhibited protective effects, mitigating BPA-induced disruptions across multiple pathways. For the first time, our study models endometrial organoids, advancing understanding of environmental impacts on reproductive health.

New roles for Bacillus thuringiensis in the removal of environmental pollutants

For a long time, the well-known Gram-positive bacterium Bacillus thuringiensis (Bt) has been extensively studied and developed as a biological insecticide for Lepidoptera and Coleoptera pests due to its ability to secrete a large number of specific insecticidal proteins. In recent years, studies have found that Bt strains can also potentially biodegrade residual pollutants in the environment. Many researchers have isolated Bt strains from multiple sites polluted by exogenous compounds and characterized and identified their xenobiotic-degrading potential. Furthermore, its pathway for degradation was also investigated at molecular level, and a number of major genes/enzymes responsible for degradation have been explored. At present, a variety of xenobiotics involved in degradation in Bt have been reported, including inorganic pollutants (used in the field of heavy metal biosorption and recovery and precious metal recovery and regeneration), pesticides (chlorpyrifos, cypermethrin, 2,2-dichloropropionic acid, etc.), organic tin, petroleum and polycyclic aromatic hydrocarbons, reactive dyes (congo red, methyl orange, methyl blue, etc.), and ibuprofen, among others. In this paper, the biodegrading ability of Bt is reviewed according to the categories of related pollutants, so as to emphasize that Bt is a powerful agent for removing environmental pollutants.

Bisphenols-A Threat to the Natural Environment

Negative public sentiment built up around bisphenol A (BPA) follows growing awareness of the frequency of this chemical compound in the environment. The increase in air, water, and soil contamination by BPA has also generated the need to replace it with less toxic analogs, such as Bisphenol F (BPF) and Bisphenol S (BPS). However, due to the structural similarity of BPF and BPS to BPA, questions arise about the safety of their usage. The toxicity of BPA, BPF, and BPS towards humans and animals has been fairly well understood. The biodegradability potential of microorganisms towards each of these bisphenols is also widely recognized. However, the scale of their inhibitory pressure on soil microbiomes and soil enzyme activity has not been estimated. These parameters are extremely important in determining soil health, which in turn also influences plant growth and development. Therefore, in this manuscript, knowledge has been expanded and systematized regarding the differences in toxicity between BPA and its two analogs. In the context of the synthetic characterization of the effects of bisphenol permeation into the environment, the toxic impact of BPA, BPF, and BPS on the microbiological and biochemical parameters of soils was traced. The response of cultivated plants to their influence was also analyzed.

The roles of membrane permeability and efflux pumps in the toxicity of bisphenol S analogues (2,4-bisphenol S and bis-(3-allyl-4-hydroxyphenyl) sulfone) to Escherichia coli K12

Bisphenol S (BPS) analogues are a group of recently reported emerging contaminants in the environment. Bacteria are important components of food webs. However, the potential risks of BPS analogues in bacteria have not been fully addressed. The toxicity effects and related mechanisms of two BPS analogues with different molecular weights (2,4-bisphenol S (2,4-BPS) and bis-(3-allyl-4-hydroxyphenyl) sulfone (TGSA)) on Escherichia coli K12 were compared. The minimum inhibitory concentration (MIC) of 2,4-BPS in the wild-type of E. coli K12 was lower than that of TGSA. The membrane permeability of the wild-type increased significantly after exposed to the same concentrations (0.5-50 nmol L^-1) of 2,4-BPS and TGSA. In addition, 2,4-BPS induced more significant changes in membrane permeability than TGSA. Hormetic effects of 2,4-BPS and TGSA in the wild-type strain were noted in the levels of outer membrane proteins (ompC and ompF), multidrug efflux pump acriflavine resistance B (acrB) and type II topoisomerases. Transcriptomic results indicated these two BPS analogues inhibited the function of ABC transporters. In contrast to TGSA, 2,4-BPS affected DNA replication, tricarboxylic acid cycle, oxidative phosphorylation, and inhibited energy metabolism. Compared with wild-type strain, the ΔacrB mutant strain showed enhanced susceptibility to 2,4-BPS and TGSA with their MICs reduced by 20% and 11%, respectively. Deletion of the acrB affected the growth characteristics and induced stronger oxidative stress than the wild-type strain when exposed to 2,4-BPS or TGSA. The results suggested that 2,4-BPS were more toxic to E. coli K12 than TGSA in the concentration range of 0.5-50 nmol L^-1, which was supported by the evidence from their impacts on membrane permeability and efflux pumps.

Understanding the role of graphene oxide in affecting PAHs biodegradation by microorganisms: An integrated analysis using 16SrRNA, metatranscriptomic, and metabolomic approaches

Graphene oxide (GO)-promoted microbial degradation technology is considered an important strategy to eliminate polycyclic aromatic hydrocarbons (PAHs) in the environment; however, the mechanism by which GO affects microbial degradation of PAHs has not been fully studied. Thus, this study aimed to analyze the effect of GO-microbial interaction on PAHs degradation at the microbial community structure, community gene expression, and metabolic levels using multi-omics combined technology. We treated PAHs-contaminated soil samples with different concentrations of GO and analyzed the soil samples for microbial diversity after 14 and 28 days. After a short exposure, GO reduced the diversity of soil microbial community but increased potential degrading microbial abundance, promoting PAHs biodegradation. This promotion effect was further influenced by the GO concentration. In a short period of time, GO upregulated the expression of genes involved in microbial movement (flagellar assembly), bacterial chemotaxis, two-component system, and phosphotransferase system in the soil microbial community and increased the probability of microbial contact with PAHs. Biosynthesis of amino acids and carbon metabolism of microorganisms were accelerated, thereby increasing the degradation of PAHs. With the extension of time, the degradation of PAHs stagnated, which may be due to the weakened stimulation of GO on microorganisms. The results showed that screening specific degrading microorganisms, increasing the contact area between microorganisms and PAHs, and prolonging the stimulation of GO on microorganisms were important means to improve the biodegradation efficiency of PAHs in soil. This study elucidates how GO affects microbial PAHs degradation and provides important insights for the application of GO-assisted microbial degradation technology.

Efficient biodegradation of tris-(2-chloroisopropyl) phosphate by a novel strain Amycolatopsis sp. FT-1: Process optimization, mechanism studies and toxicity changes

In this study, a newly isolated strain Amycolatopsis sp. FT-1 was confirmed to be an efficient tris-(2-chloroisopropyl) phosphate (TCPP) degrader. The maximum degradation efficiency of 100 % was achieved when glucose concentration was 6.0 g/L, TCPP concentration was 1.1 mg/L, pH was 6.3 and temperature was 35 °C. Proteome analysis indicated that TCPP was transformed into diester, monoester and ketone product through hydrolysis by phosphoesterase and oxidation mediated by proteins involved in bio-Fenton reaction. The increased expression of proteins serving as organic hydroperoxides scavenger and two subunits of xanthine dehydrogenase enabled Amycolatopsis sp. FT-1 to defend against TCPP-induced oxidative damage. Meanwhile, proteins involved in the resistance to proteotoxic stress were found to be up-regulated, including Hsp70 protein, ATP-dependent Clp protease proteolytic subunit, elongation factor G and trehalose synthesis-related enzymes. The overexpression of TetR/AcrR family transcriptional regulator and multidrug efflux transporter also benefited the survival of Amycolatopsis sp. FT-1 under TCPP stress. Luminescent bacteria test showed that biotoxicity of TCPP was remarkably decreased after biodegradation by Amycolatopsis sp. FT-1. To the best of our knowledge, this is the first study to report the biotransformation of TCPP by pure strain and to offer important insights into the proteomic mechanisms of TCPP microbial degradation.

Use of high-resolution metabolomics to assess the biological perturbations associated with maternal exposure to Bisphenol A and Bisphenol F among pregnant African American women

BACKGROUND

Human and animal exposure to bisphenol A (BPA) has been associated with adverse developmental and reproductive effects. The molecular mechanisms by which BPA exposure exerts its effects are not well-understood, even less known about its analogues bisphenol F (BPF). To address these knowledge gaps, we conducted an untargeted metabolome-wide association study (MWAS) to identify metabolic perturbations associated with BPA/BPF exposures in a pregnant African American cohort.

METHODS

From a subset of study participants enrolled in the Atlanta African American Maternal-Child cohort, we collected both urine samples, for targeted exposure assessment of BPA (N = 230) and BPF (N = 48), and serum samples, for high-resolution metabolomics (HRM) profiling (N = 230), during early pregnancy (8-14 weeks' gestation). Using an established untargeted HRM workflow consisting of MWAS modeling, pathway enrichment analysis, and chemical annotation and confirmation, we investigated the potential metabolic pathways and features associated with BPA/BPF exposures.

RESULTS

The geometric mean creatinine-adjusted concentrations of urinary BPA and BPF were 0.85 ± 2.58 and 0.70 ± 4.71 µg/g creatinine, respectively. After false positive discovery rate correction at 20 % level, 264 and 733 unique metabolic features were significantly associated with urinary BPA and BPF concentrations, representing 10 and 12 metabolic pathways, respectively. Three metabolic pathways, including steroid hormones biosynthesis, lysine and lipoate metabolism, were significantly associated with both BPA and BPF exposure. Using chemical standards, we have confirmed the chemical identity of 16 metabolites significantly associated with BPA or BPF exposure.

CONCLUSIONS

Our findings support that exposure to BPA and BPF in pregnant women is associated with the perturbation of aromatic amino acid metabolism, xenobiotics metabolism, steroid biosynthesis, and other amino acid metabolism closely linked to stress responses, inflammation, neural development, reproduction, and weight regulation.

Insights into biodegradation mechanisms of triphenyl phosphate by a novel fungal isolate and its potential in bioremediation of contaminated river sediment

In this study, Aspergillus sydowii FJH-1 isolated from soil was verified to be a novel triphenyl phosphate (TPhP) degrader. Biodegradation efficiency of TPhP by Aspergillus sydowii FJH-1 exceeded 90% within 6 days under the optimal conditions (pH 4-9, 30 ℃, initial concentration less than 20 mg/L). Proteomics analysis uncovered the proteins perhaps involved in hydrolysis, hydroxylation, methylation and sulfonation of TPhP and the primary intracellular adaptive responses of Aspergillus sydowii FJH-1 to TPhP stress. The expression of carboxylic ester hydrolase along with several thioredoxin- and glutathione-dependent oxidoreductases were induced to withstand the toxicity of TPhP. The presence of TPhP also caused obvious upregulation of proteins concerned with glycolysis, pentose phosphate pathway and tricarboxylic acid cycle. Data from toxicological tests confirmed that the cytotoxicity and phytotoxicity of TPhP was effectively decreased after treatment with Aspergillus sydowii FJH-1. Additionally, bioaugmentation with Aspergillus sydowii FJH-1 was available for promoting TPhP removal in real water and water-sediment system. Collectively, the present study offered a deeper insight into the biodegradation mechanism and pathway of TPhP by a newly screened fungal strain Aspergillus sydowii FJH-1 and validated the feasibility of applying this novel degrader in the bioremediation of TPhP-polluted matrices.

Bisphenol A-A Dangerous Pollutant Distorting the Biological Properties of Soil

Bisphenol A (BPA), with its wide array of products and applications, is currently one of the most commonly produced chemicals in the world. A narrow pool of data on BPA–microorganism–plant interaction mechanisms has stimulated the following research, the aim of which has been to determine the response of the soil microbiome and crop plants, as well as the activity of soil enzymes exposed to BPA pressure. A range of disturbances was assessed, based on the activity of seven soil enzymes, an abundance of five groups of microorganisms, and the structural diversity of the soil microbiome. The condition of the soil was verified by determining the values of the indices: colony development (CD), ecophysiological diversity (EP), the Shannon–Weaver index, and the Simpson index, tolerance of soil enzymes, microorganisms and plants (TI_BPA), biochemical soil fertility (BA₂₁), the ratio of the mass of aerial parts to the mass of plant roots (PR), and the leaf greenness index: Soil and Plant Analysis Development (SPAD). The data brought into sharp focus the adverse effects of BPA on the abundance and ecophysiological diversity of fungi. A change in the structural composition of bacteria was noted. Bisphenol A had a more beneficial effect on the Proteobacteria than on bacteria from the phyla Actinobacteria or Bacteroidetes. The microbiome of the soil exposed to BPA was numerously represented by bacteria from the genus Sphingomonas. In this object pool, the highest fungal OTU richness was achieved by the genus Penicillium, a representative of the phylum Ascomycota. A dose of 1000 mg BPA kg⁻¹ d.m. of soil depressed the activity of dehydrogenases, urease, acid phosphatase and β-glucosidase, while increasing that of alkaline phosphatase and arylsulfatase. Spring oilseed rape and maize responded significantly negatively to the soil contamination with BPA.

Label-Free Quantitative Proteomic Analysis of the Global Response to Indole-3-Acetic Acid in Newly Isolated Pseudomonas sp. Strain LY1

Indole-3-acetic acid (IAA), known as a common plant hormone, is one of the most distributed indole derivatives in the environment, but the degradation mechanism and cellular response network to IAA degradation are still not very clear. The objective of this study was to elucidate the molecular mechanisms of IAA degradation at the protein level by a newly isolated strain Pseudomonas sp. LY1. Label-free quantitative proteomic analysis of strain LY1 cultivated with IAA or citrate/NH₄Cl was applied. A total of 2,604 proteins were identified, and 227 proteins have differential abundances in the presence of IAA, including 97 highly abundant proteins and 130 less abundant proteins. Based on the proteomic analysis an IAA degrading (iad) gene cluster in strain LY1 containing IAA transformation genes (organized as iadHABICDEFG), genes of the β-ketoadipate pathway for catechol and protocatechuate degradation (catBCA and pcaABCDEF) were identified. The iadA, iadB, and iadE-disrupted mutants lost the ability to grow on IAA, which confirmed the role of the iad cluster in IAA degradation. Degradation intermediates were analyzed by HPLC, LC-MS, and GC-MS analysis. Proteomic analysis and identified products suggested that multiple degradation pathways existed in strain LY1. IAA was initially transformed to dioxindole-3-acetic acid, which was further transformed to isatin. Isatin was then transformed to isatinic acid or catechol. An in-depth data analysis suggested oxidative stress in strain LY1 during IAA degradation, and the abundance of a series of proteins was upregulated to respond to the stress, including reaction oxygen species (ROS) scavenging, protein repair, fatty acid synthesis, RNA protection, signal transduction, chemotaxis, and several membrane transporters. The findings firstly explained the adaptation mechanism of bacteria to IAA degradation.

Comparative toxicity reduction potential of UV/sodium percarbonate and UV/hydrogen peroxide treatments for bisphenol A in water: An integrated analysis using chemical, computational, biological, and metabolomic approaches

Bisphenol A (BPA) is a common industrial chemical with significant adverse impacts on biological systems as an environmental contaminant. UV/hydrogen peroxide (UV/H₂O₂) is a well-established technology for BPA treatment in water while UV/sodium percarbonate (UV/SPC) is an emerging technology with unclear biological impacts of treated effluent. Therefore, in this study, the toxicity evaluation of BPA solution treated with UV/H₂O₂ and UV/SPC was preformed and compared based on transformation products (TPs) profile, quantitative structure-activity relationship (QSAR), Escherichia coli (E. coli) toxicity assays, and metabolomic analysis. TPs with hydroxylation, double-ring split, and single-ring cleavage were generated from BPA during the treatments with both technologies, but TPs with quinonation were specifically detected in UV/H₂O₂ treated solution at the UV dose of 1470 mJ cm^-2. QSAR prediction based on TPs profile (excluding benzoquinone TPs) suggested that UV/H₂O₂ and UV/SPC treatments of BPA may increase matrix toxicity due to the formation of multi-hydroxylated TPs; however decreased bioaccumulation potential of all TPs may mitigate the increase of toxicity by reducing the chance of TPs to reach the concentration of toxicity threshold. In vivo assays with E. coli showed inhibited cell growth, arrested cell cycle, and increased cell death in BPA solution treated with UV/H₂O₂ at the UV dose of 1470 mJ cm^-2. Metabolomic analysis indicated that BPA solution treated with UV/H₂O₂ at UV dose of 1470 mJ cm^-2 impacted E. coli metabolism differently than other solutions with unique inhibition on glycerolipid metabolism. Moreover, BPA interfered in various metabolic pathways including alanine, aspartate and glutamate metabolism, starch and sucrose metabolism, pentose phosphate pathway, and lysine degradation, which were mitigated after the treatments. UV/SPC showed advantage over UV/H₂O₂ of attenuated impact on butanoate metabolism with UV irradiation. This study has generated valuable data for better understanding of biological impacts of BPA and its solutions treated with UV/H₂O₂ or UV/SPC, thus providing insights for their application prospect for water and wastewater treatment.

Soil Microbiome Response to Contamination with Bisphenol A, Bisphenol F and Bisphenol S

The choice of the study objective was affected by numerous controversies and concerns around bisphenol F (BPF) and bisphenol S (BPS)—analogues of bisphenol A (BPA). The study focused on the determination and comparison of the scale of the BPA, BPF, and BPS impact on the soil microbiome and its enzymatic activity. The following parameters were determined in soil uncontaminated and contaminated with BPA, BPF, and BPS: the count of eleven groups of microorganisms, colony development (CD) index, microorganism ecophysiological diversity (EP) index, genetic diversity of bacteria and activity of dehydrogenases (Deh), urease (Ure), catalase (Cat), acid phosphatase (Pac), alkaline phosphatase (Pal), arylsulphatase (Aryl) and β-glucosidase (Glu). Bisphenols A, S and F significantly disrupted the soil homeostasis. BPF is regarded as the most toxic, followed by BPS and BPA. BPF and BPS reduced the abundance of Proteobacteria and Acidobacteria and increased that of Actinobacteria. Unique types of bacteria were identified as well as the characteristics of each bisphenol: Lysobacter, Steroidobacter, Variovorax, Mycoplana, for BPA, Caldilinea, Arthrobacter, Cellulosimicrobium and Promicromonospora for BPF and Dactylosporangium Geodermatophilus, Sphingopyxis for BPS. Considering the strength of a negative impact of bisphenols on the soil biochemical activity, they can be arranged as follows: BPS > BPF > BPA. Urease and arylsulphatase proved to be the most susceptible and dehydrogenases the least susceptible to bisphenols pressure, regardless of the study duration.

Maternal exposure to bisphenol A during pregnancy interferes ovaries development of F1 female mice

This study was conducted to investigate the effects of maternal exposure bisphenol A (BPA) on ovaries development of F1 female mice. The BPA exposure model of pregnant mice was prepared by intragastric administration of BPA at the doses of 0, 2.5, 5, 10, 20, 40 mg kg^-1 d^-1 at gestation day (GD) 0.5-17.5. The ovarian index of the offspring mice was calculated at postnatal day (PND) 21 and PND 56. The results showed that BPA at 5 mg/kg, 10 mg/kg, 20 mg/kg and 40 mg/kg significantly increased the abortion rate of the pregnant mice, and each dose of BPA significantly reduced the survival rate of the pups (P < 0.01 or P < 0.05). Besides, there was a non-monotonic dose-response relationship between serum hormone, ovarian receptor levels and BPA in F1 females at both PND 21 and 56. BPA increased the ovarian/uterine index in F1 females at both PND 21 and 56, increased the mRNA relative transcript levels of ovarian ERα, PgR and DNA methyltransferase (DNMT) in F1 females at PND 21, while decreased at PND 56 (P < 0.01 or P < 0.05). BPA also increased the relative expression of caspase-7, caspase-9, bax, inhibited the relative expression of bcl-2 in F1 females at both PND 21 and 56, and increased the apoptosis rate in the ovaries in F1 mice at PND 56 (P < 0.01). The number of follicles in the ovary was increased in F1 females at PND 21, and the ovaries were significantly atrophied when sexual maturity (PND 56). Our results indicated that BPA could disturb the contents of DNMT and make reproductive injury to the offspring females.

Metabolic and proteomic mechanism of benzo[a]pyrene degradation by Brevibacillus brevis

Benzo[a]pyrene (BaP) is a model compound of polycyclic aromatic hydrocarbons. The relationship between its toxicity and some target biomolecules has been investigated. To reveal the interactions of BaP biodegradation and metabolic network, BaP intermediates, proteome, carbon metabolism and ion transport were analyzed. The results show that 76% BaP was degraded by Brevibacillus brevis within 7 d through the cleavage of aromatic rings with the production of 1-naphthol and 2-naphthol. During this process, the expression of xylose isomerase was induced for xylose metabolism, whereas, α-cyclodextrin could no longer be metabolized. Lactic acid, acetic acid and oxalic acid at 0.1-1.2 mg dm^-3 were released stemming from their enhanced biosynthesis in the pathways of pyruvate metabolism and citrate cycle, while 5-7 mg dm^-3 of PO₄^3- were transported for energy metabolism. The relative abundance of 43 proteins was significantly increased for pyruvate metabolism, citrate cycle, amino acid metabolism, purine metabolism, ribosome metabolism and protein synthesis.

Genome sequence of a spore-laccase forming, BPA-degrading Bacillus sp. GZB isolated from an electronic-waste recycling site reveals insights into BPA degradation pathways

Bisphenol A (BPA) is a synthetic chemical with known deleterious effects on biota. A genome sequencing project is an important starting point for designing a suitable BPA bioremediation process, because it provides valuable genomic information about the physiological, metabolic, and genetic potential of the microbes used for the treatment. This study explored genomic insights provided by the BPA-degrading strain Bacillus sp. GZB, previously isolated from electronic-waste-dismantling site. The GZB genome is a circular chromosome, comprised of a total of 4,077,007 bp with G+C content comprising 46.2%. Genome contained 23 contigs encoded by 3881 protein-coding genes with nine rRNA and 53 tRNA genes. A comparative study demonstrated that strain GZB bloomed with some potential features as compared to other Bacillus species. In addition, strain GZB developed spore cells and displayed laccase activity while growing at elevated stress levels. Most importantly, strain GZB contained many protein-coding genes associated with BPA degradation, as well as the degradation of several other compounds. The protein-coding genes in the genome revealed the genetic mechanisms associated with the BPA degradation by strain GZB. This study predicts four possible degradation pathways for BPA, contributing to the possible use of strain GZB to remediate different polluted environments in the future.

Bioremediation of triphenyl phosphate in river water microcosms: Proteome alteration of Brevibacillus brevis and cytotoxicity assessments

Triphenyl phosphate (TPHP), an organophosphate flame retardant, was detected in river water samples collected from an electronic waste recycling area in Guiyu, Southern China. The concentrations of TPHP ranged from not detected to 347.2 ng/L, with an average of 138.8 ng/L. The bioaugmentation potential of Brevibacillus brevis on TPHP biodegradation by aerobic microcosms contained in river water from Guiyu was assessed. The results showed that TPHP degradation efficiency was significantly improved to 97.9% by bioaugmentation with B. brevis after 96 h incubation. A total of 182 significantly changed proteins in B. brevis were identified and quantified by isobaric tags for relative and absolute quantification (iTRAQ) in response to TPHP stress. The differentially expressed proteins were mainly associated with energy metabolism, lipid metabolism, cell wall biosynthesis, amino acid transport, and metabolism. The identification that proteins of B. brevis respond to TPHP existence provides novel insights into biodegradation mechanisms of bacteria under environmental stress. Additionally, cytotoxicity assays indicated that the degrading intermediates of TPHP, namely diphenyl phosphate and phenyl phosphate, were less cytotoxic to human HepG2 cells compared with TPHP. Collectively, these findings suggest that aerobic bioaugmentation with degrading microorganisms is a potential strategy for in situ treatment of TPHP-contaminated sites.