1
|
Tan J, Lamont GJ, Scott DA. Tobacco-enhanced biofilm formation by Porphyromonas gingivalis and other oral microbes. Mol Oral Microbiol 2024:10.1111/omi.12450. [PMID: 38229003 PMCID: PMC11250950 DOI: 10.1111/omi.12450] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2023] [Revised: 12/08/2023] [Accepted: 12/25/2023] [Indexed: 01/18/2024]
Abstract
Microbial biofilms promote pathogenesis by disguising antigens, facilitating immune evasion, providing protection against antibiotics and other antimicrobials and, generally, fostering survival and persistence. Environmental fluxes are known to influence biofilm formation and composition, with recent data suggesting that tobacco and tobacco-derived stimuli are particularly important mediators of biofilm initiation and development in vitro and determinants of polymicrobial communities in vivo. The evidence for tobacco-augmented biofilm formation by oral bacteria, tobacco-induced oral dysbiosis, tobacco-resistance strategies, and bacterial physiology is summarized herein. A general overview is provided alongside specific insights gained through studies of the model and archetypal, anaerobic, Gram-negative oral pathobiont, Porphyromonas gingivalis.
Collapse
Affiliation(s)
- Jinlian Tan
- Department of Oral Immunology and Infectious Diseases,
University of Louisville, Louisville, KY, USA
| | - Gwyneth J. Lamont
- Department of Oral Immunology and Infectious Diseases,
University of Louisville, Louisville, KY, USA
| | - David A. Scott
- Department of Oral Immunology and Infectious Diseases,
University of Louisville, Louisville, KY, USA
- Center for Microbiomics, Inflammation and Pathogenicity,
University of Louisville, Louisville, KY, USA
| |
Collapse
|
2
|
Huang D, Wang Y, Xiao J, Wang Y, Zhu X, Xu B, Wang M. Scavenging of reactive oxygen species effectively reduces Pseudomonas aeruginosa biofilms through disrupting policing. ENVIRONMENTAL RESEARCH 2023; 220:115182. [PMID: 36586713 DOI: 10.1016/j.envres.2022.115182] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2022] [Revised: 12/22/2022] [Accepted: 12/27/2022] [Indexed: 06/17/2023]
Abstract
Biofilm formation is likely to contribute greatly to antibiotic resistance in bacteria and therefore the efficient removal of bacterial biofilms needs addressing urgently. Here, we reported that the supplement of non-inhibitory concentration of N-acetyl-L-cysteine (NAC), a common reactive oxygen species (ROS) scavenger, can significantly reduce the biomass of mature Pseudomonas aeruginosa biofilms (corroborated by crystal violet assay and laser scanning confocal microscopy). 1 mM NAC increased the cheater (ΔlasR mutant) frequency to 89.4 ± 1.5% in the evolved PAO1 after the 15-day treatment. Scavenging of ROS by NAC induced the collapse of P. aeruginosa biofilms, but it did not alter quorum sensing-regulated genes expression (e.g., hcnC and cioAB) and hydrogen cyanide production. The replenishment of public good protease contributed to the recovery of biofilm biomass, indicating the role of disrupting policing in biofilm inhibition. Furthermore, 7 typical ROS scavengers (e.g., superoxide dismutase, catalase and peroxidase, etc.) also effectively inhibited mature P. aeruginosa biofilms. This study demonstrates that scavenging of ROS can promote the selective control of P. aeruginosa biofilms through policing disruption as a targeted biofilm control strategy in complex water environments.
Collapse
Affiliation(s)
- Dan Huang
- School of Environmental Science and Engineering, Zhejiang Gongshang University, Hangzhou, 310012, China; Zhejiang Provincial Key Laboratory of Solid Waste Treatment and Recycling, Hangzhou, 310012, China
| | - Yujie Wang
- School of Environmental Science and Engineering, Zhejiang Gongshang University, Hangzhou, 310012, China
| | - Junwei Xiao
- School of Environmental Science and Engineering, Zhejiang Gongshang University, Hangzhou, 310012, China
| | - Yufan Wang
- School of Environmental Science and Engineering, Zhejiang Gongshang University, Hangzhou, 310012, China
| | - Xinyu Zhu
- Eco-Environmental Science Research and Design Institute of Zhejiang Province, Hangzhou, 310007, China
| | - Baile Xu
- Institute of Soil and Water Resources and Environmental Science, College of Environment and Resource Sciences, Zhejiang University, Hangzhou, 310058, China
| | - Meizhen Wang
- School of Environmental Science and Engineering, Zhejiang Gongshang University, Hangzhou, 310012, China; Zhejiang Provincial Key Laboratory of Solid Waste Treatment and Recycling, Hangzhou, 310012, China.
| |
Collapse
|
3
|
Yan H, Liu C, Yu W, Zhu X, Chen B. The aggregate distribution of Pseudomonas aeruginosa on biochar facilitates quorum sensing and biofilm formation. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 856:159034. [PMID: 36167127 DOI: 10.1016/j.scitotenv.2022.159034] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2022] [Revised: 09/12/2022] [Accepted: 09/21/2022] [Indexed: 06/16/2023]
Abstract
Biochar when applied into soil, together with soil clay minerals, may provide habitats for soil microbes and shift soil microbial community structure. Although several mechanisms have been proposed to explain the effects of biochar on microbial community, the impact of biochar on quorum sensing (QS) and QS-regulated behavior is poorly understood. In this study, we compared the effects of biochar and three common soil minerals (i.e., montmorillonite, kaolinite, and goethite) on QS and biofilm formation. Pseudomonas aeruginosa PAO1 with complete QS systems was selected as a model organism. Our results showed that biochar and goethite effectively promoted microbial QS and biofilm formation, while montmorillonite and kaolinite posed no significant effect. Live/Dead staining, SEM and density-dependent QS activity indicated that biochar was beneficial to cell viability maintenance and cell aggregations, which improved the efficiency of intercellular communications through QS. QS mutant strain experiments confirmed that biochar enhanced PAO1 biofilm formation by promoting QS. Goethite promoted biofilm formation with a different mechanism that cell debris induced by iron ions and positive charge on goethite surface provided raw materials for bacterial biofilm formation. Our findings provide evidence that the presence of biochar can enhance QS and biofilm formation through a feedforward loop of the QS system. This contributes to better understand biochar-mediated microbial cell to cell communications through QS.
Collapse
Affiliation(s)
- Huicong Yan
- Department of Environmental Science, Zhejiang University, Hangzhou 310058, China; Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Hangzhou 310058, China.
| | - Congcong Liu
- Department of Environmental Science, Zhejiang University, Hangzhou 310058, China; Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Hangzhou 310058, China.
| | - Wentao Yu
- Department of Environmental Science, Zhejiang University, Hangzhou 310058, China; Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Hangzhou 310058, China.
| | - Xiaomin Zhu
- College of Resources and Environment, Anhui Agricultural University, Hefei 230036, China.
| | - Baoliang Chen
- Department of Environmental Science, Zhejiang University, Hangzhou 310058, China; Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Hangzhou 310058, China.
| |
Collapse
|
4
|
Song C, Huang F, Liu L, Zhou Q, Zhang D, Fang Q, Lei H, Niu H. Characterization and prebiotic properties of pectin polysaccharide from Clausena lansium (Lour.) Skeels fruit. Int J Biol Macromol 2022; 194:412-421. [PMID: 34813784 DOI: 10.1016/j.ijbiomac.2021.11.083] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2021] [Revised: 10/29/2021] [Accepted: 11/14/2021] [Indexed: 01/07/2023]
Abstract
Pectins have proven to be advantageous for human health as they regulate beneficial microbial communities and enhance immunity. The fruit of Clausena lansium (Lour.) Skeels (Wampee), also referred to as "treasure in fruit", is rich in pectin polysaccharides. In this study, a homogalacturonan-type pectin (CCP2) with a molecular weight of 8.9 × 104 Da and degree of esterification of 42.86% was isolated from Wampee fruit. The gut microbiota regulation and phagocytosis-enhancing properties of CCP2 were examined in vivo and in vitro, respectively. Oral administration of CCP2 dramatically decreased the abundance of Bacteroidetes and increased the abundance of Firmicutes in intestinal bacteria in mice. The content of short-chain fatty acids in the feces also significantly improved. Moreover, CCP2 exhibited excellent phagocytosis-enhancing activities on RAW 264.7 macrophages. These results suggested that CCP2 could be a potential gut microbiota regulator and phagocytosis-enhancer, which could be used in food products to promote health through beneficial manipulation of gut microbiota.
Collapse
Affiliation(s)
- Can Song
- School of Pharmacy, Southwest Medical University, Luzhou 646000, Sichuan, China
| | - Feihong Huang
- School of Pharmacy, Southwest Medical University, Luzhou 646000, Sichuan, China
| | - Linyu Liu
- School of Pharmacy, Southwest Medical University, Luzhou 646000, Sichuan, China
| | - Quan Zhou
- School of Pharmacy, Southwest Medical University, Luzhou 646000, Sichuan, China
| | - Dan Zhang
- School of Pharmacy, Southwest Medical University, Luzhou 646000, Sichuan, China
| | - Qi Fang
- School of Pharmacy, Southwest Medical University, Luzhou 646000, Sichuan, China
| | - Hui Lei
- School of Pharmacy, Southwest Medical University, Luzhou 646000, Sichuan, China.
| | - Hong Niu
- School of Pharmacy, Southwest Medical University, Luzhou 646000, Sichuan, China.
| |
Collapse
|
5
|
Freitas PNN, Rovida AFDS, Silva CR, Pileggi SAV, Olchanheski LR, Pileggi M. Specific quorum sensing molecules are possibly associated with responses to herbicide toxicity in a Pseudomonas strain. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2021; 289:117896. [PMID: 34358867 DOI: 10.1016/j.envpol.2021.117896] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Revised: 07/25/2021] [Accepted: 08/01/2021] [Indexed: 06/13/2023]
Abstract
Pesticides contribute to pest control and increase agricultural production; however, they are toxic to non-target organisms, and they contaminate the environment. The exposure of bacteria to these substances can lead to the need for physiological and structural changes for survival, which can be determined by genes whose expression is regulated by quorum sensing (QS). However, it is not yet clear whether these processes can be induced by herbicides. Thus, the aim of this work was to determine whether there is a QS response system in the Pseudomonas fluorescens CMA55 strain that is modulated by herbicides. This strain was isolated from water storage tanks used for washing pesticide packaging and was tested against herbicides containing saflufenacil, glyphosate, sulfentrazone, 2,4-D, and dicamba as active molecules. Our results showed that in the presence of herbicides containing saflufenacil and glyphosate (the latter was not present at the bacterial isolation site) the strain had a profile of QS signaling molecules that may be involved in controlling the production of reactive oxygen species. Alternatively, the same strain, in the presence of sulfentrazone (it was not present at the bacterial isolation site), 2,4-D and dicamba-containing herbicides, presented another profile of molecules that may be involved in different stages of biofilm formation. These findings, as a first screening, suggest that this strain used strategies to activate antioxidant enzymes and biofilm production under the signaling of QS molecules to respond to herbicides, regardless of previous contact, representing a model of phenotypic plasticity for adaptation to agricultural environments that can be used in studies of herbicide bioremediation.
Collapse
Affiliation(s)
- Paloma Nathane Nunes Freitas
- Laboratory of Environmental Microbiology, Biological and Health Sciences Sector, Department of Structural and Molecular Biology and Genetics, Ponta Grossa State University, Ponta Grossa, Paraná, Brazil
| | | | - Caroline Rosa Silva
- Laboratory of Environmental Microbiology, Biological and Health Sciences Sector, Department of Structural and Molecular Biology and Genetics, Ponta Grossa State University, Ponta Grossa, Paraná, Brazil
| | - Sônia Alvim Veiga Pileggi
- Laboratory of Environmental Microbiology, Biological and Health Sciences Sector, Department of Structural and Molecular Biology and Genetics, Ponta Grossa State University, Ponta Grossa, Paraná, Brazil
| | - Luiz Ricardo Olchanheski
- Laboratory of Environmental Microbiology, Biological and Health Sciences Sector, Department of Structural and Molecular Biology and Genetics, Ponta Grossa State University, Ponta Grossa, Paraná, Brazil
| | - Marcos Pileggi
- Laboratory of Environmental Microbiology, Biological and Health Sciences Sector, Department of Structural and Molecular Biology and Genetics, Ponta Grossa State University, Ponta Grossa, Paraná, Brazil.
| |
Collapse
|
6
|
Rovida AFDS, Costa G, Santos MI, Silva CR, Freitas PNN, Oliveira EP, Pileggi SAV, Olchanheski RL, Pileggi M. Herbicides Tolerance in a Pseudomonas Strain Is Associated With Metabolic Plasticity of Antioxidative Enzymes Regardless of Selection. Front Microbiol 2021; 12:673211. [PMID: 34239509 PMCID: PMC8258386 DOI: 10.3389/fmicb.2021.673211] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2021] [Accepted: 05/10/2021] [Indexed: 11/19/2022] Open
Abstract
Agriculture uses many food production chains, and herbicides participate in this process by eliminating weeds through different biochemical strategies. However, herbicides can affect non-target organisms such as bacteria, which can suffer damage if there is no efficient control of reactive oxygen species. It is not clear, according to the literature, whether the efficiency of this control needs to be selected by the presence of xenobiotics. Thus, the Pseudomonas sp. CMA 6.9 strain, collected from biofilms in an herbicide packaging washing tank, was selected for its tolerance to pesticides and analyzed for activities of different antioxidative enzymes against the herbicides Boral®, absent at the isolation site, and Heat®, present at the site; both herbicides have the same mode of action, the inhibition of the enzyme protoporphyrinogen oxidase. The strain showed tolerance to both herbicides in doses up to 45 times than those applied in agriculture. The toxicity of these herbicides, which is greater for Boral®, was assessed by means of oxidative stress indicators, growth kinetics, viability, and amounts of peroxide and malondialdehyde. However, the studied strain showed two characteristic antioxidant response systems for each herbicide: glutathione-s-transferase acting to control malondialdehyde in treatments with Boral®; and catalase, ascorbate peroxidase, and guaiacol peroxidase in the control of peroxide induced by Heat®. It is possible that this modulation of the activity of different enzymes independent of previous selection characterizes a system of metabolic plasticity that may be more general in the adaptation of microorganisms in soil and water environments subjected to chemical contaminants. This is relevant to the impact of pesticides on the diversity and abundance of microbial species as well as a promising line of metabolic studies in microbial consortia for use in bioremediation.
Collapse
Affiliation(s)
| | - Gessica Costa
- Laboratory of Environmental Microbiology, Biological and Health Sciences Sector, Department of Structural and Molecular Biology and Genetics, State University of Ponta Grossa, Ponta Grossa, Brazil
| | - Mariana Inglês Santos
- Laboratory of Environmental Microbiology, Biological and Health Sciences Sector, Department of Structural and Molecular Biology and Genetics, State University of Ponta Grossa, Ponta Grossa, Brazil
| | - Caroline Rosa Silva
- Laboratory of Environmental Microbiology, Biological and Health Sciences Sector, Department of Structural and Molecular Biology and Genetics, State University of Ponta Grossa, Ponta Grossa, Brazil
| | - Paloma Nathane Nunes Freitas
- Laboratory of Environmental Microbiology, Biological and Health Sciences Sector, Department of Structural and Molecular Biology and Genetics, State University of Ponta Grossa, Ponta Grossa, Brazil
| | - Elizangela Paz Oliveira
- Department of Biotechnology, Genetics and Cell Biology, State University of Maringá, Maringá, Brazil
| | - Sônia Alvim Veiga Pileggi
- Laboratory of Environmental Microbiology, Biological and Health Sciences Sector, Department of Structural and Molecular Biology and Genetics, State University of Ponta Grossa, Ponta Grossa, Brazil
| | - Ricardo Luiz Olchanheski
- Laboratory of Environmental Microbiology, Biological and Health Sciences Sector, Department of Structural and Molecular Biology and Genetics, State University of Ponta Grossa, Ponta Grossa, Brazil
| | - Marcos Pileggi
- Laboratory of Environmental Microbiology, Biological and Health Sciences Sector, Department of Structural and Molecular Biology and Genetics, State University of Ponta Grossa, Ponta Grossa, Brazil
| |
Collapse
|
7
|
Thermal and non-thermal treatment effects on Staphylococcus aureus biofilms formed at different temperatures and maturation periods. Food Res Int 2020; 137:109432. [PMID: 33233114 DOI: 10.1016/j.foodres.2020.109432] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2020] [Revised: 05/30/2020] [Accepted: 06/09/2020] [Indexed: 11/20/2022]
Abstract
The objective of this study was to investigate the effect of temperature and maturation period on the resistance of Staphylococcus aureus biofilms to thermal and non-thermal treatments. First, biofilm development was compared at three different temperatures (15, 25, and 37°C) for 5 days. The cell population at 15 and 25°C remained relatively consistent approximately at 6.3 log CFU/cm2, whereas 37°C resulted in the highest cell population on day 1 (7.6 log CFU/cm2) followed by a continual decline. Then, biofilm resistance to steam and sodium hypochlorite (NaOCl) treatments was evaluated. Obtained results highlighted that biofilms had different resistance to both treatments depending on development conditions. Specifically, steam treatment of 10 s eliminated 4.1 log CFU/cm2 of the biofilm formed at 25°C for 5 days. The same treatment inactivated over 5 log population of biofilms developed in other temperature and maturation period conditions. Treatment with NaOCl reduced approximately 1 log CFU/cm2 of biofilm cells developed at 25°C for 5 days. However, inactivation was found to be over 2 log CFU/cm2 under other development conditions. An extracellular polymeric substances (EPS) quantification using 96-well plates and stainless steel coupons was conducted. In the 96-well plate experiment, it was found that the highest amount of polysaccharide was secreted at 25°C (p < 0.05), while total biomass and protein contents were greatest at 37°C (p < 0.05). No significant difference in EPS content was observed for stainless steel, but the results displayed a similar trend to the 96-well plate. In particular, biofilms developed at 25°C tended to secret the highest amount of polysaccharide, which aligned with the current literature. This finding indicated that polysaccharide was the main contribution to the enhanced resistance of S. aureus biofilms. Overall, it was shown that biofilms formed at 25°C for 5 days exhibited the greatest resistance to thermal and nonthermal treatments due to the elevated exopolysaccharide secretion. This study demonstrates that temperature and maturation period significantly affect the resistance of S. aureus biofilms to thermal and non-thermal treatments.
Collapse
|
8
|
Joshi SR, Jagtap S, Basu B, Deobagkar DD, Ghosh P. Construction, analysis and validation of co-expression network to understand stress adaptation in Deinococcus radiodurans R1. PLoS One 2020; 15:e0234721. [PMID: 32579573 PMCID: PMC7314050 DOI: 10.1371/journal.pone.0234721] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2019] [Accepted: 06/02/2020] [Indexed: 01/12/2023] Open
Abstract
Systems biology based approaches have been effectively utilized to mine high throughput data. In the current study, we have performed system-level analysis for Deinococcus radiodurans R1 by constructing a gene co-expression network based on several microarray datasets available in the public domain. This condition-independent network was constructed by Weighted Gene Co-expression Network Analysis (WGCNA) with 61 microarray samples from 9 different experimental conditions. We identified 13 co-expressed modules, of which, 11 showed functional enrichments of one or more pathway/s or biological process. Comparative analysis of differentially expressed genes and proteins from radiation and desiccation stress studies with our co-expressed modules revealed the association of cyan with radiation response. Interestingly, two modules viz darkgreen and tan was associated with radiation as well as desiccation stress responses. The functional analysis of these modules showed enrichment of pathways important for adaptation of radiation or desiccation stress. To decipher the regulatory roles of these stress responsive modules, we identified transcription factors (TFs) and then calculated a Biweight mid correlation between modules hub gene and the identified TFs. We obtained 7 TFs for radiation and desiccation responsive modules. The expressions of 3 TFs were validated in response to gamma radiation using qRT-PCR. Along with the TFs, selected close neighbor genes of two important TFs, viz., DR_0997 (CRP) and DR_2287 (AsnC family transcriptional regulator) in the darkgreen module were also validated. In our network, among 13 hub genes associated with 13 modules, the functionality of 5 hub genes which are annotated as hypothetical proteins (hypothetical hub genes) in D. radiodurans genome has been revealed. Overall the study provided a better insight of pathways and regulators associated with relevant DNA damaging stress response in D. radiodurans.
Collapse
Affiliation(s)
- Suraj R. Joshi
- Bioinformatics Centre, Savitribai Phule Pune University, Pune, India
- Molecular Biology Research Laboratory, Department of Zoology, Savitribai Phule Pune University, Pune, India
- Molecular Biology Division, Bhabha Atomic Research Centre, Mumbai, India
| | - Surabhi Jagtap
- Bioinformatics Centre, Savitribai Phule Pune University, Pune, India
| | - Bhakti Basu
- Molecular Biology Division, Bhabha Atomic Research Centre, Mumbai, India
| | - Deepti D. Deobagkar
- Molecular Biology Research Laboratory, Department of Zoology, Savitribai Phule Pune University, Pune, India
| | - Payel Ghosh
- Bioinformatics Centre, Savitribai Phule Pune University, Pune, India
- * E-mail: ,
| |
Collapse
|
9
|
Zaman N, Azam SS. From normal to competo-allosteric regulation: insights into the binding pattern dynamics of DSPI protein of Pseudomonas aeruginosa. J Biomol Struct Dyn 2020; 39:538-557. [PMID: 31903856 DOI: 10.1080/07391102.2020.1711805] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
DSPI, a putative enoyl-coenzyme A (CoA) hydratase/isomerase, is anticipated to be involved in the synthesis of cis-2-decenoic acid (CDA), a quorum sensing (QS) signal molecule present in the superbug Pseudomonas aeruginosa. The current study not only adapts a broad-spectrum strategy for the lucid design of small molecule modulators but also provides novel allosteric inhibitors for DSPI, to investigate its function and potential as a therapeutic target. Docking analysis revealed that the compound 10252273, bound to the specific allosteric site, interacted with Glu118, unique amino acid residue of the active binding pocket, hence indicates the presence of a competitive allosteric site. The current study thus identifies and characterizes inhibitors by targeting the normal binding site and also reports the presence of the competo-allosteric site in the same binding tunnel as the normal site. Molecular docking studies proposed two chemical compounds that share a benzamide-benzimidazole (BB) backbone as potent inhibitors that can obstruct the mechanism of DSPI by targeting both the normal and proposed allosteric binding sites. MD simulations further revealed the disruption of the normal binding site due to the displacement of critical residues Cys146 and Glu118. The rearrangement of H-bond pattern, pi-pi interactions, and strong hydrophobic interactions were observed at both the binding sites. The allosteric pocket inhibitor exhibited improved binding energy than the normal site inhibitor based on MMGBSA and MMPBSA analysis. With subsequent characterization, the current study reveals the allosteric binding site and provides insights into the drug binding mechanism of DSPI.Communicated by Ramaswamy H. Sarma.
Collapse
Affiliation(s)
- Naila Zaman
- Computational Biology Lab, National Center for Bioinformatics, Quaid-i-Azam University, Islamabad, Pakistan
| | - Syed Sikander Azam
- Computational Biology Lab, National Center for Bioinformatics, Quaid-i-Azam University, Islamabad, Pakistan
| |
Collapse
|
10
|
Tang H, Zhang Y, Hu J, Li Y, Li N, Wang M. Mixture of different Pseudomonas aeruginosa SD-1 strains in the efficient bioaugmentation for synthetic livestock wastewater treatment. CHEMOSPHERE 2019; 237:124455. [PMID: 31376694 DOI: 10.1016/j.chemosphere.2019.124455] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Revised: 05/30/2019] [Accepted: 07/24/2019] [Indexed: 06/10/2023]
Abstract
Strains selection for inoculation is the key to the successful construction of a bioaugmentation system, a promising strategy for specific pollutant removal. Pseudomonas aeruginosa SD-1 wild-type (WT) strain exhibited high capacity for biofilm formation but low efficiency for nitrate (NO3-) removal. Meanwhile, quorum sensing deficient strain ΔlasR showed excellent efficiency for NO3- removal but poor capability for colonization in activated sludge. The opposite effect of biofilm formation and NO3- removal exist in WT or ΔlasR, which limits the construction of bioaugmentation system of strain SD-1 and its application. To solve this issue, a mixture of WT and ΔlasR (v/v = 1:1) was used to construct a bioaugmentation system. Compared with the inoculation of WT or ΔlasR alone, the mixed inoculation not only was beneficial for activated sludge development but also for pollutant removal. The indicators for activated sludge including the abundance of P. aeruginosa, the sludge volume index and the average particle size in mixed inoculated reactors were close to those of reactors with single and repeated inoculation of WT. The effluent of chemical oxygen demand (COD) and NO3--N were stable at 3.9-22.6 mg L-1 and 0-5.53 mg L-1 after d 3, respectively. This study presents a detailed case on the ecological tradeoff of colonization and pollutant removal of inoculated strains during bioaugmentation. The results provide information on the appropriate conditions for application of P. aeruginosa SD-1 for livestock wastewater treatment and further enrich our ecological understanding of bioaugmentation.
Collapse
Affiliation(s)
- Huiming Tang
- School of Environmental Science and Engineering, Zhejiang Gongshang University, Hangzhou, 310012, PR China
| | - Yunyun Zhang
- School of Environmental Science and Engineering, Zhejiang Gongshang University, Hangzhou, 310012, PR China
| | - Jingming Hu
- School of Environmental Science and Engineering, Zhejiang Gongshang University, Hangzhou, 310012, PR China
| | - Yue Li
- School of Environmental Science and Engineering, Zhejiang Gongshang University, Hangzhou, 310012, PR China
| | - Na Li
- School of Environmental Science and Engineering, Zhejiang Gongshang University, Hangzhou, 310012, PR China; Zhejiang Provincial Key Laboratory of Solid Waste Treatment and Recycling, Hangzhou, 310012, PR China
| | - Meizhen Wang
- School of Environmental Science and Engineering, Zhejiang Gongshang University, Hangzhou, 310012, PR China; Zhejiang Provincial Key Laboratory of Solid Waste Treatment and Recycling, Hangzhou, 310012, PR China.
| |
Collapse
|