1
|
Liu K, Huang S, Zhang L, Xiong Y, Wang X, Bao Y, Li D, Li J. Efficient production of single cell protein from biogas slurry using screened alkali-salt-tolerant Debaryomyces hansenii. BIORESOURCE TECHNOLOGY 2024; 393:130119. [PMID: 38040306 DOI: 10.1016/j.biortech.2023.130119] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2023] [Revised: 11/25/2023] [Accepted: 11/26/2023] [Indexed: 12/03/2023]
Abstract
Production of single cell protein (SCP) by recovering ammonia nitrogen from biogas slurry shows great potential against protein scarcity and unsustainable production of plant and animal proteins. Herein, a high-alkali-salt-tolerant yeast strain, Debaryomyces hansenii JL8-0, was isolated and demonstrated for high-efficient SCP production. This strain grew optimally at pH 8.50 and 2500 mg/L NH4+-N, and it could efficiently utilize acetate as the additional carbon source. Under optimal conditions, SCP biomass of 32.21 g/L and productivity of 0.32 g/L·h-1 were obtained in fed-batch fermentation. Remarkably, nearly complete (97.40 %) ammonia nitrogen from biogas slurry was recovered, probably due to its high affinity for NH4+-N. Altogether, this strain showed advantages in terms of cell biomass titer, productivity, and yield. A cultivation strategy was proposed by co-culturing D. hansenii with other compatible yeast strains to achieve high-efficient SCP production from biogas slurry, which could be a promising alternative technology for biogas slurry treatment.
Collapse
Affiliation(s)
- Keyun Liu
- CAS Key Laboratory of Environmental and Applied Microbiology, Environmental Microbiology Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Siyuan Huang
- CAS Key Laboratory of Environmental and Applied Microbiology, Environmental Microbiology Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Lu Zhang
- CAS Key Laboratory of Environmental and Applied Microbiology, Environmental Microbiology Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041, China
| | - Yingjie Xiong
- CAS Key Laboratory of Environmental and Applied Microbiology, Environmental Microbiology Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041, China
| | - Xiaoyan Wang
- Chemical Engineering College, Inner Mongolia University of Technology, Hohhot 010050, China
| | - Yali Bao
- Chemical Engineering College, Inner Mongolia University of Technology, Hohhot 010050, China
| | - Dong Li
- CAS Key Laboratory of Environmental and Applied Microbiology, Environmental Microbiology Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jiabao Li
- CAS Key Laboratory of Environmental and Applied Microbiology, Environmental Microbiology Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041, China; University of Chinese Academy of Sciences, Beijing 100049, China.
| |
Collapse
|
2
|
Albacar M, Zekhnini A, Pérez-Valle J, Martínez JL, Casamayor A, Ariño J. Transcriptomic profiling of the yeast Komagataella phaffii in response to environmental alkalinization. Microb Cell Fact 2023; 22:63. [PMID: 37013612 PMCID: PMC10071690 DOI: 10.1186/s12934-023-02074-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2023] [Accepted: 03/27/2023] [Indexed: 04/05/2023] Open
Abstract
BACKGROUND Adaptation to alkalinization of the medium in fungi involves an extensive remodeling of gene expression. Komagataella phaffii is an ascomycetous yeast that has become an organism widely used for heterologous protein expression. We explore here the transcriptional impact of moderate alkalinization in this yeast, in search of suitable novel promoters able to drive transcription in response to the pH signal. RESULTS In spite of a minor effect on growth, shifting the cultures from pH 5.5 to 8.0 or 8.2 provokes significant changes in the mRNA levels of over 700 genes. Functional categories such as arginine and methionine biosynthesis, non-reductive iron uptake and phosphate metabolism are enriched in induced genes, whereas many genes encoding iron-sulfur proteins or members of the respirasome were repressed. We also show that alkalinization is accompanied by oxidative stress and we propose this circumstance as a common trigger of a subset of the observed changes. PHO89, encoding a Na+/Pi cotransporter, appears among the most potently induced genes by high pH. We demonstrate that this response is mainly based on two calcineurin-dependent response elements located in its promoter, thus indicating that alkalinization triggers a calcium-mediated signal in K. phaffii. CONCLUSIONS This work defines in K. phaffii a subset of genes and diverse cellular pathways that are altered in response to moderate alkalinization of the medium, thus setting the basis for developing novel pH-controlled systems for heterologous protein expression in this fungus.
Collapse
Affiliation(s)
- Marcel Albacar
- Institut de Biotecnologia i Biomedicina & Departament de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, Cerdanyola del Vallès, 08193, Spain
| | - Abdelghani Zekhnini
- Institut de Biotecnologia i Biomedicina & Departament de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, Cerdanyola del Vallès, 08193, Spain
| | - Jorge Pérez-Valle
- Institut de Biotecnologia i Biomedicina & Departament de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, Cerdanyola del Vallès, 08193, Spain
| | - José L Martínez
- Department of Biotechnology and Biomedicine, Section for Synthetic Biology, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Antonio Casamayor
- Institut de Biotecnologia i Biomedicina & Departament de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, Cerdanyola del Vallès, 08193, Spain
| | - Joaquín Ariño
- Institut de Biotecnologia i Biomedicina & Departament de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, Cerdanyola del Vallès, 08193, Spain.
| |
Collapse
|
3
|
Ochoa-Gutiérrez D, Reyes-Torres AM, de la Fuente-Colmenares I, Escobar-Sánchez V, González J, Ortiz-Hernández R, Torres-Ramírez N, Segal-Kischinevzky C. Alternative CUG Codon Usage in the Halotolerant Yeast Debaryomyces hansenii: Gene Expression Profiles Provide New Insights into Ambiguous Translation. J Fungi (Basel) 2022; 8:jof8090970. [PMID: 36135695 PMCID: PMC9502446 DOI: 10.3390/jof8090970] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2022] [Revised: 09/10/2022] [Accepted: 09/12/2022] [Indexed: 12/04/2022] Open
Abstract
The halotolerant yeast Debaryomyces hansenii belongs to the CTG-Ser1 clade of fungal species that use the CUG codon to translate as leucine or serine. The ambiguous decoding of the CUG codon is relevant for expanding protein diversity, but little is known about the role of leucine–serine ambiguity in cellular adaptations to extreme environments. Here, we examine sequences and structures of tRNACAG from the CTG-Ser1 clade yeasts, finding that D. hansenii conserves the elements to translate ambiguously. Then, we show that D. hansenii has tolerance to conditions of salinity, acidity, alkalinity, and oxidative stress associated with phenotypic and ultrastructural changes. In these conditions, we found differential expression in both the logarithmic and stationary growth phases of tRNASer, tRNALeu, tRNACAG, LeuRS, and SerRS genes that could be involved in the adaptive process of this yeast. Finally, we compare the proteomic isoelectric points and hydropathy profiles, detecting that the most important variations among the physicochemical characteristics of D. hansenii proteins are in their hydrophobic and hydrophilic interactions with the medium. We propose that the ambiguous translation, i.e., leucylation or serynation, on translation of the CUG-encoded residues, could be linked to adaptation processes in extreme environments.
Collapse
Affiliation(s)
- Daniel Ochoa-Gutiérrez
- Laboratorio de Biología Molecular y Genómica, Departamento de Biología Celular, Facultad de Ciencias, Universidad Nacional Autónoma de México, Avenida Universidad # 3000, Cd. Universitaria, Coyoacán, Mexico City 04510, Mexico
- Posgrado en Ciencias Biológicas, Universidad Nacional Autónoma de México, Avenida Universidad # 3000, Cd. Universitaria, Coyoacán, Mexico City 04510, Mexico
| | - Anya M. Reyes-Torres
- Laboratorio de Biología Molecular y Genómica, Departamento de Biología Celular, Facultad de Ciencias, Universidad Nacional Autónoma de México, Avenida Universidad # 3000, Cd. Universitaria, Coyoacán, Mexico City 04510, Mexico
| | - Ileana de la Fuente-Colmenares
- Laboratorio de Biología Molecular y Genómica, Departamento de Biología Celular, Facultad de Ciencias, Universidad Nacional Autónoma de México, Avenida Universidad # 3000, Cd. Universitaria, Coyoacán, Mexico City 04510, Mexico
| | - Viviana Escobar-Sánchez
- Laboratorio de Biología Molecular y Genómica, Departamento de Biología Celular, Facultad de Ciencias, Universidad Nacional Autónoma de México, Avenida Universidad # 3000, Cd. Universitaria, Coyoacán, Mexico City 04510, Mexico
| | - James González
- Laboratorio de Biología Molecular y Genómica, Departamento de Biología Celular, Facultad de Ciencias, Universidad Nacional Autónoma de México, Avenida Universidad # 3000, Cd. Universitaria, Coyoacán, Mexico City 04510, Mexico
| | - Rosario Ortiz-Hernández
- Laboratorio de Microscopía Electrónica, Departamento de Biología Celular, Facultad de Ciencias, Universidad Nacional Autónoma de México, Avenida Universidad # 3000, Cd. Universitaria, Coyoacán, Mexico City 04510, Mexico
| | - Nayeli Torres-Ramírez
- Laboratorio de Microscopía Electrónica, Departamento de Biología Celular, Facultad de Ciencias, Universidad Nacional Autónoma de México, Avenida Universidad # 3000, Cd. Universitaria, Coyoacán, Mexico City 04510, Mexico
| | - Claudia Segal-Kischinevzky
- Laboratorio de Biología Molecular y Genómica, Departamento de Biología Celular, Facultad de Ciencias, Universidad Nacional Autónoma de México, Avenida Universidad # 3000, Cd. Universitaria, Coyoacán, Mexico City 04510, Mexico
- Correspondence:
| |
Collapse
|
4
|
Estrada-Ávila AK, González-Hernández JC, Calahorra M, Sánchez NS, Peña A. Xylose and yeasts: A story beyond xylitol production. Biochim Biophys Acta Gen Subj 2022; 1866:130154. [PMID: 35461922 DOI: 10.1016/j.bbagen.2022.130154] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2021] [Revised: 03/30/2022] [Accepted: 04/13/2022] [Indexed: 11/16/2022]
Abstract
Six different yeasts were used to study their metabolism of glucose and xylose, and mainly their capacity to produce ethanol and xylitol. The strains used were Candida guilliermondii, Debaryomyces hansenii, Saccharomyces cerevisiae, Kluyveromyces marxianus, Meyerozyma guilliermondii and Clavispora lusitaniae, four isolated from a rural mezcal fermentation facility. All of them produced ethanol when the substrate was glucose. When incubated in a medium containing xylose instead of glucose, only K. marxianus and M. guilliermondii were able to produce ethanol from xylose. On the other hand, all of them could produce some xylitol from xylose, but the most active in this regard were K. marxianus, M. guilliermondii, Candida lusitaniae, and C. guilliermondii with the highest amount of xylitol produced. The capacity of all strains to take up glucose and xylose was also studied. Xylose, in different degrees, produced a redox imbalance in all yeasts. Respiration capacity was also studied with glucose or xylose, where C. guilliermondii, D. hansenii, K. marxianus and M. guilliermondii showed higher cyanide resistant respiration when grown in xylose. Neither xylose transport nor xylitol production were enhanced by an acidic environment (pH 4), which can be interpreted as the absence of a proton/sugar symporter mechanism for xylose transport, except for C. lusitaniae. The effects produced by xylose and their magnitude depend on the background of the studied yeast and the conditions in which these are studied.
Collapse
Affiliation(s)
- Alejandra Karina Estrada-Ávila
- Departamento de Genética Molecular, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Circuito Exterior s/n, Ciudad Universitaria, 04510, México City (+5255)56225633, Mexico
| | - Juan Carlos González-Hernández
- Tecnológico Nacional de México / Instituto Tecnológico de Morelia, Departamento de Ingeniería Química y Bioquímica, Av. Tecnológico # 1500. Colonia Lomas de Santiaguito, 58120 Morelia, Michoacán, Mexico
| | - Martha Calahorra
- Departamento de Genética Molecular, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Circuito Exterior s/n, Ciudad Universitaria, 04510, México City (+5255)56225633, Mexico
| | - Norma Silvia Sánchez
- Departamento de Genética Molecular, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Circuito Exterior s/n, Ciudad Universitaria, 04510, México City (+5255)56225633, Mexico
| | - Antonio Peña
- Departamento de Genética Molecular, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Circuito Exterior s/n, Ciudad Universitaria, 04510, México City (+5255)56225633, Mexico.
| |
Collapse
|
5
|
Yeasts Inhabiting Extreme Environments and Their Biotechnological Applications. Microorganisms 2022; 10:microorganisms10040794. [PMID: 35456844 PMCID: PMC9028089 DOI: 10.3390/microorganisms10040794] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2022] [Revised: 04/06/2022] [Accepted: 04/06/2022] [Indexed: 11/17/2022] Open
Abstract
Yeasts are microscopic fungi inhabiting all Earth environments, including those inhospitable for most life forms, considered extreme environments. According to their habitats, yeasts could be extremotolerant or extremophiles. Some are polyextremophiles, depending on their growth capacity, tolerance, and survival in the face of their habitat’s physical and chemical constitution. The extreme yeasts are relevant for the industrial production of value-added compounds, such as biofuels, lipids, carotenoids, recombinant proteins, enzymes, among others. This review calls attention to the importance of yeasts inhabiting extreme environments, including metabolic and adaptive aspects to tolerate conditions of cold, heat, water availability, pH, salinity, osmolarity, UV radiation, and metal toxicity, which are relevant for biotechnological applications. We explore the habitats of extreme yeasts, highlighting key species, physiology, adaptations, and molecular identification. Finally, we summarize several findings related to the industrially-important extremophilic yeasts and describe current trends in biotechnological applications that will impact the bioeconomy.
Collapse
|
6
|
Molaei S, Moussavi G, Talebbeydokhti N, Shekoohiyan S. Biodegradation of the petroleum hydrocarbons using an anoxic packed-bed biofilm reactor with in-situ biosurfactant-producing bacteria. JOURNAL OF HAZARDOUS MATERIALS 2022; 421:126699. [PMID: 34330075 DOI: 10.1016/j.jhazmat.2021.126699] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2021] [Revised: 07/16/2021] [Accepted: 07/18/2021] [Indexed: 06/13/2023]
Abstract
The present study employed an anoxic packed bed biofilm reactor (AnPBR) inoculated with in-situ biosurfactant-producing bacteria for the biodegradation of petroleum wastewater. Highly acclimated biomass decreased the start-up phase period and with increasing the initial total petroleum hydrocarbon (TPH) concentration from 1.5 to 4 g/L was accompanied by TPH and chemical oxygen demand (COD) removal efficiencies of above 99% and 96%, respectively. Decreasing hydraulic retention time (HRT) from 24 to 6 h caused an increase in the specific hydrocarbon utilization rate value from 0.45 to 1.66 gTPH/gbiomass.d. Moreover, dehydrogenase activity, surfactin, and rhamnolipid reached 31.8 μgTF/gbiomass.d, 95.1, and 27.1 mg/L, respectively. The biodegradation kinetic coefficients such as K, Ks, Kd, Y and µmax were 0.784 (d-1), 0.005 (g/L), 0.138 (d-1), 0.569 (gVSS/gCOD), and 0.446 (d-1), respectively. Dropping of bioreactor performance, especially TPH removal efficiency from 99% to 37.6% in the absence of nitrate after 10 days, indicates anoxic metabolism has been the dominant biodegradation pathway. The effluent chromatogram of gas chromatography/flame ionization detector (GC/FID) showed aliphatic, cyclic aliphatic, and aromatic hydrocarbons efficiently degraded. According to the high degradation rate of AnPBR in different operational parameters, it can be recommended for the treatment of oil-contaminated wastewater.
Collapse
Affiliation(s)
- Saeed Molaei
- Department of Environmental Health Engineering, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran; Department of Civil and Environmental Engineering, Shiraz University, Shiraz, Iran
| | - Gholamreza Moussavi
- Department of Environmental Health Engineering, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran.
| | | | - Sakine Shekoohiyan
- Department of Environmental Health Engineering, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran.
| |
Collapse
|
7
|
Donzella S, Capusoni C, Pellegrino L, Compagno C. Bioprocesses with Reduced Ecological Footprint by Marine Debaryomyces hansenii Strain for Potential Applications in Circular Economy. J Fungi (Basel) 2021; 7:jof7121028. [PMID: 34947010 PMCID: PMC8706832 DOI: 10.3390/jof7121028] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Revised: 11/25/2021] [Accepted: 11/29/2021] [Indexed: 11/16/2022] Open
Abstract
The possibility to perform bioprocesses with reduced ecological footprint to produce natural compounds and catalyzers of industrial interest is pushing the research for salt tolerant microorganisms able to grow on seawater-based media and able to use a wide range of nutrients coming from waste. In this study we focused our attention on a Debaryomyces hansenii marine strain (Mo40). We optimized cultivation in a bioreactor at low pH on seawater-based media containing a mixture of sugars (glucose and xylose) and urea. Under these conditions the strain exhibited high growth rate and biomass yield. In addition, we characterized potential applications of this yeast biomass in food/feed industry. We show that Mo40 can produce a biomass containing 45% proteins and 20% lipids. This strain is also able to degrade phytic acid by a cell-bound phytase activity. These features represent an appealing starting point for obtaining D. hansenii biomass in a cheap and environmentally friendly way, and for potential use as an additive or to replace unsustainable ingredients in the feed or food industries, as this species is included in the QPS EFSA list (Quality Presumption as Safe-European Food Safety Authority).
Collapse
|
8
|
Navarrete C, Frost AT, Ramos-Moreno L, Krum MR, Martínez JL. A physiological characterization in controlled bioreactors reveals a novel survival strategy for Debaryomyces hansenii at high salinity. Yeast 2021; 38:302-315. [PMID: 33305394 DOI: 10.1002/yea.3544] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2020] [Revised: 11/25/2020] [Accepted: 12/09/2020] [Indexed: 12/13/2022] Open
Abstract
Debaryomyces hansenii is traditionally described as a halotolerant non-conventional yeast and has served as a model organism for the study of osmotolerance and salt tolerance mechanisms in eukaryotic systems for the past 30 years. However, unraveling of D. hansenii's biotechnological potential has always been difficult due to the persistent limitations in the availability of efficient molecular tools described for this yeast. Additionally, there is a lack of consensus and contradictory information along the recent years that limits a comprehensive understanding of its central carbon metabolism, mainly due to a lack of physiological studies in controlled and monitored environments. Moreover, there is little consistency in the culture conditions (media composition, temperature, and pH among others) used by different groups, which makes it complicated when trying to get prevalent conclusions on behavioral patterns. In this work, we present for the first time a characterization of D. hansenii in batch cultivations using highly controlled lab-scale bioreactors. Our findings contribute to a more complete picture of the central carbon metabolism and the external pH influence on the yeast's ability to tolerate high Na+ and K+ concentrations, pointing to a differential effect of both salts, as well as a positive effect in cell performance when low environmental pH values are combined with a high sodium concentration in the media. Finally, a novel survival strategy at very high salinity (2 M) is proposed for this yeast, as well as potential outcomes for its use in industrial biotechnology applications. TAKE AWAY: High salt concentrations stimulate respiration in Debaryomyces hansenii. Sodium exerts a stronger positive impact on cell performance than potassium. μmax is higher at a combination of low pH, high salt, and high temperature. Concentrations of 2 M salt result in slower growth but increased biomass yield. The positive effect of salts is enhanced at low glucose concentration.
Collapse
Affiliation(s)
- Clara Navarrete
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Kongens Lyngby, Denmark
| | - August T Frost
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Laura Ramos-Moreno
- Department of Microbiology, Campus de Rabanales, University of Córdoba, Córdoba, Spain
| | - Mette R Krum
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Kongens Lyngby, Denmark
| | - José L Martínez
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Kongens Lyngby, Denmark
| |
Collapse
|
9
|
Prospective production of fructose and single cell protein from date palm waste. ELECTRON J BIOTECHN 2020. [DOI: 10.1016/j.ejbt.2020.09.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
|
10
|
Contribution of the mitogen-activated protein kinase Hog1 to the halotolerance of the marine yeast Debaryomyces hansenii. Curr Genet 2020; 66:1135-1153. [PMID: 32719935 DOI: 10.1007/s00294-020-01099-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Revised: 07/10/2020] [Accepted: 07/17/2020] [Indexed: 10/23/2022]
Abstract
Halotolerant species are adapted to dealing continually with hyperosmotic environments, having evolved strategies that are uncommon in other organisms. The HOG pathway is the master system that regulates the cellular adaptation under these conditions; nevertheless, apart from the importance of Debaryomyces hansenii as an organism representative of the halotolerant class, its HOG1 pathway has been poorly studied, due to the difficulty of applying conventional recombinant DNA technology. Here we describe for the first time the phenotypic characterisation of a null HOG1 mutant of D. hansenii. Dhhog1Δ strain was found moderately resistant to 1 M NaCl and sensitive to higher concentrations. Under hyperosmotic shock, DhHog1 fully upregulated transcription of DhSTL1 and partially upregulated that of DhGPD1. High osmotic stress lead to long-term inner glycerol accumulation that was partially dependent on DhHog1. These observations indicated that the HOG pathway is required for survival under high external osmolarity but dispensable under low and mid-osmotic conditions. It was also found that DhHog1 can regulate response to alkali stress during hyperosmotic conditions and that it plays a role in oxidative and endoplasmic reticulum stress. Taken together, these results provide new insight into the contribution of this MAPK in halotolerance of this yeast.
Collapse
|
11
|
Kaur J, Anand V, Srivastava S, Bist V, Tripathi P, Naseem M, Nand S, Khare P, Srivastava PK, Bisht S, Srivastava S. Yeast strain Debaryomyces hansenii for amelioration of arsenic stress in rice. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2020; 195:110480. [PMID: 32203774 DOI: 10.1016/j.ecoenv.2020.110480] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2019] [Revised: 03/11/2020] [Accepted: 03/13/2020] [Indexed: 06/10/2023]
Abstract
Arsenic (As) is a serious threat for environment and human health. Rice, the main staple crop is more prone to As uptake. Bioremediation strategies with heavy metal tolerant rhizobacteria are well known. The main objective of the study was to characterize arsenic-resistant yeast strains, capable of mitigating arsenic stress in rice. Three yeast strains identified as Debaryomyces hansenii (NBRI-Sh2.11), Candida tropicalis (NBRI-B3.4) and Candida dubliniensis (NBRI-3.5) were found to have As reductase activity. D. hansenii with higher As tolerance has As expulsion ability as compared to other two strains. Inoculation of D. hansenii showed improved detoxification through scavenging of reactive oxygen species (ROS) by the modulation of SOD and APX activity under As stress condition in rice. Modulation of defense responsive gene (NADPH, GST, GR) along with arsR and metal cation transporter are the probable mechanism of As detoxification as evident with improved membrane (electrolyte leakage) stability. Reduced grain As (~40% reduction) due to interaction with D. hansenii (NBRI-Sh2.11) further validated it's As mitigation property in rice. To the best of our knowledge D. hansenii has been reported for the first time for arsenic stress mitigation in rice with improved growth and nutrient status of the plant.
Collapse
Affiliation(s)
- Jasvinder Kaur
- Division of Microbial Technology, CSIR-National Botanical Research Institute, Rana Pratap Marg, Lucknow, 226 001, India
| | - Vandana Anand
- Division of Microbial Technology, CSIR-National Botanical Research Institute, Rana Pratap Marg, Lucknow, 226 001, India; Academy of Scientific and Innovative Research, AcSIR, Ghaziabad, 201002, India
| | - Sonal Srivastava
- Division of Microbial Technology, CSIR-National Botanical Research Institute, Rana Pratap Marg, Lucknow, 226 001, India; Academy of Scientific and Innovative Research, AcSIR, Ghaziabad, 201002, India
| | - Vidisha Bist
- Division of Microbial Technology, CSIR-National Botanical Research Institute, Rana Pratap Marg, Lucknow, 226 001, India; Academy of Scientific and Innovative Research, AcSIR, Ghaziabad, 201002, India
| | | | - Mariya Naseem
- Environmental Technology Division, CSIR-National Botanical Research Institute, Rana Pratap Marg, Lucknow, 226 001, India
| | - Sampurna Nand
- Environmental Technology Division, CSIR-National Botanical Research Institute, Rana Pratap Marg, Lucknow, 226 001, India
| | - Puja Khare
- Chemistry Division, CSIR-CIMAP, Lucknow, India
| | | | - Saraswati Bisht
- Department of Botany, Kumaun University, Nainital, 263002, India
| | - Suchi Srivastava
- Academy of Scientific and Innovative Research, AcSIR, Ghaziabad, 201002, India.
| |
Collapse
|
12
|
CgCmk1 Activates CgRds2 To Resist Low-pH Stress in Candida glabrata. Appl Environ Microbiol 2020; 86:AEM.00302-20. [PMID: 32245757 DOI: 10.1128/aem.00302-20] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2020] [Accepted: 03/27/2020] [Indexed: 02/07/2023] Open
Abstract
In Candida glabrata, the transcription factor CgRds2 has been previously characterized as a regulator of glycerophospholipid metabolism, playing a crucial role in the response to osmotic stress. Here, we report that CgRds2 is also involved in the response to pH 2.0 stress. At pH 2.0, the deletion of CgRDS2 led to reduced cell growth and survival, by 33% and 57%, respectively, compared with those of the wild-type strain. These adverse phenotypes resulted from the downregulation of genes related to energy metabolism in the Cgrds2Δ strain at pH 2.0, which led to a 34% reduction of the intracellular ATP content and a 24% decrease in membrane permeability. In contrast, the overexpression of CgRDS2 rescued the growth defect of the Cgrds2Δ strain and increased cell survival at pH 2.0 by 17% compared with that of the wild-type strain, and this effect was accompanied by significant increases in ATP content and membrane permeability, by 42% and 19%, respectively. Furthermore, we found that the calcium/calmodulin-dependent protein kinase (CaMK) CgCmk1 physically interacts with the PAS domain of CgRds2, and CgCmk1 is required for CgRds2 activation and translocation from the cytoplasm to the nucleus under pH 2.0 stress. Moreover, CgCmk1 is critical for CgRds2 function in resistance to pH 2.0 stress, because cells of the Cgrds2-pas strain with a disrupted CgCmk1-CgRds2 interaction exhibited impaired energy metabolism and membrane permeability at pH 2.0. Therefore, our results indicate that CgCmk1 positively regulates CgRds2 and suggest that they promote resistance to low-pH stress by enhancing energy metabolism and membrane permeability in C. glabrata IMPORTANCE An acidic environment is the main problem in the production of organic acids in C. glabrata The present study reports that the calcium/calmodulin-dependent protein kinase CgCmk1 positively regulates CgRds2 to increase intracellular ATP content, membrane permeability, and resistance to low-pH stress. Hence, the transcription factor CgRds2 may be a potential target for improving the acid stress tolerance of C. glabrata during the fermentation of organic acids. The present study also establishes a new link between the calcium signaling pathway and energy metabolism.
Collapse
|
13
|
Leoncio L, de Almeida M, Silva M, Oliveira OMC, Moreira ÍTA, Lima DF. Evaluation of accelerated biodegradation of oil-SPM aggregates (OSAs). MARINE POLLUTION BULLETIN 2020; 152:110893. [PMID: 32479280 DOI: 10.1016/j.marpolbul.2020.110893] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Revised: 12/18/2019] [Accepted: 01/07/2020] [Indexed: 06/11/2023]
Abstract
The studies of the formation of oil-Suspended Particulate Matter (SPM) aggregates (OSAs) have advanced significantly in the scientific community, however there is a need to accelerate oil biodegradation that was dispersed by the formation of OSAs. The present research presents a pioneering character regarding the addition of nutrients as biostimulus for autochthonous hydrocarboclastic bacteria in the biodegradation of Total Petroleum Hydrocarbons (TPH) dispersed by the formation of OSAs. Water aliquots were taken over 60 days from eight bioreactors to perform ionic species analysis, pH, salinity and temperature monitoring, liquid/liquid extraction, serial dilution methodology and filter membrane. TPH quantification was performed on the gas chromatograph with a flame ionisation detector (GC-FID). The addition of nutrients contributed positively to the rate and extent of biodegradation of TPH in association with field-collected SPM. The best result found was with the lowest nutrient concentration (Bio 1) with an average of 98.65% of TPH reduction.
Collapse
Affiliation(s)
- Lua Leoncio
- Nucleo de Estudos Ambientais - NEA, Institute of Geosciences, Federal University of Bahia, Campus Ondina, R. Barão de Jeremoabo, s.n., 40170-290 Salvador, BA, Brazil.
| | - Marcos de Almeida
- Federal University of Pernambuco, Av. da Arquitetura, s.n., 50740-540 Recife, PE, Brazil
| | - Marcio Silva
- Nucleo de Estudos Ambientais - NEA, Institute of Geosciences, Federal University of Bahia, Campus Ondina, R. Barão de Jeremoabo, s.n., 40170-290 Salvador, BA, Brazil
| | - Olívia M C Oliveira
- Nucleo de Estudos Ambientais - NEA, Institute of Geosciences, Federal University of Bahia, Campus Ondina, R. Barão de Jeremoabo, s.n., 40170-290 Salvador, BA, Brazil.
| | - Ícaro T A Moreira
- Department of Environmental Engineering, Polytechnic School, Federal University of Bahia, R. Prof. Aristídes Novis, s.n., 40210-630 Salvador, BA, Brazil
| | - Danúsia Ferreira Lima
- LEPETRO, Institute of Geosciences, Federal University of Bahia, Campus Ondina, R. Barão de Jeremoabo, s.n., 40170-290 Salvador, BA, Brazil
| |
Collapse
|