1
|
Lopes JC, Veiga VP, Seminiuk B, Santos LOF, Luiz AMC, Fernandes CA, Kinasz CT, Pellizari VH, Duarte RTD. Freezing and thawing in Antarctica: characterization of antifreeze protein (AFP) producing microorganisms isolated from King George Island, Antarctica. Braz J Microbiol 2024; 55:1451-1463. [PMID: 38656427 PMCID: PMC11153389 DOI: 10.1007/s42770-024-01345-7] [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: 12/31/2023] [Accepted: 04/12/2024] [Indexed: 04/26/2024] Open
Abstract
Antarctic temperature variations and long periods of freezing shaped the evolution of microorganisms with unique survival mechanisms. These resilient organisms exhibit several adaptations for life in extreme cold. In such ecosystems, microorganisms endure the absence of liquid water and exhibit resistance to freezing by producing water-binding molecules such as antifreeze proteins (AFP). AFPs modify the ice structure, lower the freezing point, and inhibit recrystallization. The objective of this study was to select and identify microorganisms isolated from different Antarctic ecosystems based on their resistance to temperatures below 0 °C. Furthermore, the study sought to characterize these microorganisms regarding their potential antifreeze adaptive mechanisms. Samples of soil, moss, permafrost, and marine sediment were collected on King George Island, located in the South Shetland archipelago, Antarctica. Bacteria and yeasts were isolated and subjected to freezing-resistance and ice recrystallization inhibition (IR) tests. A total of 215 microorganisms were isolated, out of which 118 were molecularly identified through molecular analysis using the 16S rRNA and ITS regions. Furthermore, our study identified 24 freezing-resistant isolates, including two yeasts and 22 bacteria. A total of 131 protein extracts were subjected to the IR test, revealing 14 isolates positive for AFP production. Finally, four isolates showed both freeze-resistance and IR activity (Arthrobacter sp. BGS04, Pseudomonas sp. BGS05, Cryobacterium sp. P64, and Acinetobacter sp. M1_25C). This study emphasizes the diversity of Antarctic microorganisms with the ability to tolerate freezing conditions. These microorganisms warrant further investigation to conduct a comprehensive analysis of their antifreeze capabilities, with the goal of exploring their potential for future biotechnological applications.
Collapse
Affiliation(s)
- J C Lopes
- Laboratory of Molecular Ecology and Extremophiles, Department of Microbiology, Immunology and Parasitology, Federal University of Santa Catarina, Campus Reitor João David Ferreira Lima, s/n Trindade, 88040-900, Florianópolis, SC, Brazil
- Postgraduate Program in Biotechnology and Biosciences, Federal University of Santa Catarina, Florianópolis, Brazil
| | - V P Veiga
- Laboratory of Molecular Ecology and Extremophiles, Department of Microbiology, Immunology and Parasitology, Federal University of Santa Catarina, Campus Reitor João David Ferreira Lima, s/n Trindade, 88040-900, Florianópolis, SC, Brazil
| | - B Seminiuk
- Laboratory of Molecular Ecology and Extremophiles, Department of Microbiology, Immunology and Parasitology, Federal University of Santa Catarina, Campus Reitor João David Ferreira Lima, s/n Trindade, 88040-900, Florianópolis, SC, Brazil
| | - L O F Santos
- Laboratory of Molecular Ecology and Extremophiles, Department of Microbiology, Immunology and Parasitology, Federal University of Santa Catarina, Campus Reitor João David Ferreira Lima, s/n Trindade, 88040-900, Florianópolis, SC, Brazil
| | - A M C Luiz
- Laboratory of Molecular Ecology and Extremophiles, Department of Microbiology, Immunology and Parasitology, Federal University of Santa Catarina, Campus Reitor João David Ferreira Lima, s/n Trindade, 88040-900, Florianópolis, SC, Brazil
- Postgraduate Program in Biotechnology and Biosciences, Federal University of Santa Catarina, Florianópolis, Brazil
| | - C A Fernandes
- Laboratory of Molecular Ecology and Extremophiles, Department of Microbiology, Immunology and Parasitology, Federal University of Santa Catarina, Campus Reitor João David Ferreira Lima, s/n Trindade, 88040-900, Florianópolis, SC, Brazil
| | - C T Kinasz
- Laboratory of Molecular Ecology and Extremophiles, Department of Microbiology, Immunology and Parasitology, Federal University of Santa Catarina, Campus Reitor João David Ferreira Lima, s/n Trindade, 88040-900, Florianópolis, SC, Brazil
- Postgraduate Program in Biotechnology and Biosciences, Federal University of Santa Catarina, Florianópolis, Brazil
| | - V H Pellizari
- Oceanographic Institute, Department of Biological Oceanography, University of São Paulo, 05508-120, São Paulo, SP, Brazil
| | - R T D Duarte
- Laboratory of Molecular Ecology and Extremophiles, Department of Microbiology, Immunology and Parasitology, Federal University of Santa Catarina, Campus Reitor João David Ferreira Lima, s/n Trindade, 88040-900, Florianópolis, SC, Brazil.
- Postgraduate Program in Biotechnology and Biosciences, Federal University of Santa Catarina, Florianópolis, Brazil.
| |
Collapse
|
2
|
Insight into the Cold Adaptation Mechanism of an Aerobic Denitrifying Bacterium: Bacillus simplex H-b. Appl Environ Microbiol 2023; 89:e0192822. [PMID: 36656033 PMCID: PMC9972999 DOI: 10.1128/aem.01928-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Psychrophilic bacteria with aerobic denitrification ability have promising potential for application in nitrogen-contaminated wastewater treatment, especially under cold conditions. A better understanding of the cold adaptation mechanism during aerobic denitrification would be beneficial for the practical application of this type of functional bacterium. In this study, Bacillus simplex H-b with good denitrification performance at 5°C was used to investigate the corresponding cold tolerance mechanism. Transcriptomics and nitrogen removal characterization experiments were conducted at different temperatures (5°C, 20°C, and 30°C). At low temperatures, more nitrogen was utilized for assimilation, accompanied by the accumulation of ATP and extracellular polymeric substances (EPS), rather than transforming inorganic nitrogen in the dissimilation pathway. In addition, the proportion of unsaturated fatty acids was higher in strains cultured at low temperatures. At the molecular level, the adjustment of membrane transport, synthesis of cofactors and vitamins, and transcriptional regulators might contribute to the survival of the strain under cold conditions. Moreover, nucleotide precursor synthesis, translation, and oxidative and temperature stress response mechanisms also enhanced the resistance of strain H-b to low temperatures. The results suggest that combining multiple regulatory mechanisms and synergistic adaptation to cold stress enabled the growth and relatively high nitrogen removal rate (27.22%) of strain H-b at 5°C. By clarifying the mechanism of regulation and cold resistance of strain H-b, a theoretical foundation for enhancing the application potential of this functional bacterium for nitrogen-contaminated wastewater treatment was provided. IMPORTANCE The newly isolated aerobic denitrifying bacterium Bacillus simplex H-b removed various forms of inorganic nitrogen (nitrate, nitrite, and ammonium) from wastewater, even when the temperature was as low as 5°C. Although this environmentally functional bacterium has been suggested as a promising candidate for nitrogen-contaminated water treatment at low temperatures, understanding its cold adaptation mechanism during aerobic denitrification is limited. In this study, the cold tolerance mechanism of this strain was comprehensively explained. Furthermore, a theoretical basis for the practical application of this type of functional bacterium for nitrogen removal in cold regions is provided. The study expands our understanding of the survival strategy of psychrophilic bacteria and hence supports their further utilization in wastewater treatment applications.
Collapse
|
5
|
Zakaria NN, Convey P, Gomez-Fuentes C, Zulkharnain A, Sabri S, Shaharuddin NA, Ahmad SA. Oil Bioremediation in the Marine Environment of Antarctica: A Review and Bibliometric Keyword Cluster Analysis. Microorganisms 2021; 9:microorganisms9020419. [PMID: 33671443 PMCID: PMC7922015 DOI: 10.3390/microorganisms9020419] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Revised: 01/22/2021] [Accepted: 01/25/2021] [Indexed: 02/07/2023] Open
Abstract
Bioremediation of hydrocarbons has received much attention in recent decades, particularly relating to fuel and other oils. While of great relevance globally, there has recently been increasing interest in hydrocarbon bioremediation in the marine environments of Antarctica. To provide an objective assessment of the research interest in this field we used VOSviewer software to analyze publication data obtained from the ScienceDirect database covering the period 1970 to the present, but with a primary focus on the years 2000–2020. A bibliometric analysis of the database allowed identification of the co-occurrence of keywords. There was an increasing trend over time for publications relating to oil bioremediation in maritime Antarctica, including both studies on marine bioremediation and of the metabolic pathways of hydrocarbon degradation. Studies of marine anaerobic degradation remain under-represented compared to those of aerobic degradation. Emerging keywords in recent years included bioprospecting, metagenomic, bioindicator, and giving insight into changing research foci, such as increasing attention to microbial diversity. The study of microbial genomes using metagenomic approaches or whole genome studies is increasing rapidly and is likely to drive emerging fields in future, including rapid expansion of bioprospecting in diverse fields of biotechnology.
Collapse
Affiliation(s)
- Nur Nadhirah Zakaria
- Department of Biochemistry, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, Serdang 43400, Selangor, Malaysia; (N.N.Z.); (N.A.S.)
| | - Peter Convey
- British Antarctic Survey, NERC, High Cross, Madingley Road, Cambridge CB3 0ET, UK;
| | - Claudio Gomez-Fuentes
- Department of Chemical Engineering, Universidad de Magallanes, Avda, Bulnes 01855, Chile;
- Center for Research and Antarctic Environmental Monitoring (CIMAA), Universidad de Magallanes, Avda, Bulnes 01855, Chile
| | - Azham Zulkharnain
- Department of Bioscience and Engineering, College of Systems Engineering and Science, Shibaura Institute of Technology, 307 Fukasaku, Minuma-ku, Saitama 337-8570, Japan;
| | - Suriana Sabri
- Department of Microbiology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, Serdang 43400, Selangor, Malaysia;
| | - Noor Azmi Shaharuddin
- Department of Biochemistry, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, Serdang 43400, Selangor, Malaysia; (N.N.Z.); (N.A.S.)
| | - Siti Aqlima Ahmad
- Department of Biochemistry, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, Serdang 43400, Selangor, Malaysia; (N.N.Z.); (N.A.S.)
- Center for Research and Antarctic Environmental Monitoring (CIMAA), Universidad de Magallanes, Avda, Bulnes 01855, Chile
- National Antarctic Research Centre, B303 Level 3, Block B, IPS Building, Universiti Malaya, Kuala Lumpur 50603, Malaysia
- Correspondence:
| |
Collapse
|