1
|
Jung P, Briegel-Williams L, Werner L, Jost E, Schultz M, Nürnberg DJ, Grube M, Lakatos M. A direct PCR approach with low-biomass insert opens new horizons for molecular sciences on cryptogam communities. Appl Environ Microbiol 2024; 90:e0002424. [PMID: 38349146 PMCID: PMC10952543 DOI: 10.1128/aem.00024-24] [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: 01/11/2024] [Accepted: 01/19/2024] [Indexed: 03/21/2024] Open
Abstract
Molecular sequence data have transformed research on cryptogams (e.g., lichens, microalgae, fungi, and symbionts thereof) but methods are still strongly hampered by the small size and intermingled growth of the target organisms, poor cultivability and detrimental effects of their secondary metabolites. Here, we aim to showcase examples on which a modified direct PCR approach for diverse aspects of molecular work on environmental samples concerning biocrusts, biofilms, and cryptogams gives new options for the research community. Unlike traditional approaches, this methodology only requires biomass equivalent to colonies and fragments of 0.2 mm in diameter, which can be picked directly from the environmental sample, and includes a quick DNA lysis followed by a standardized PCR cycle that allows co-cycling of various organisms/target regions in the same run. We demonstrate that this modified method can (i) amplify the most widely used taxonomic gene regions and those used for applied and environmental sciences from single colonies and filaments of free-living cyanobacteria, bryophytes, fungi, and lichens, including their mycobionts, chlorobionts, and cyanobionts from both isolates and in situ material during co-cycling; (ii) act as a tool to confirm that the dominant lichen photobiont was isolated from the original sample; and (iii) optionally remove inhibitory secondary lichen substances. Our results represent examples which highlight the method's potential for future applications covering mycology, phycology, biocrusts, and lichenology, in particular.IMPORTANCECyanobacteria, green algae, lichens, and other cryptogams play crucial roles in complex microbial systems such as biological soil crusts of arid biomes or biofilms in caves. Molecular investigations on environmental samples or isolates of these microorganisms are often hampered by their dense aggregation, small size, or metabolism products which complicate DNA extraction and subsequent PCRs. Our work presents various examples of how a direct DNA extraction and PCR method relying on low biomass inserts can overcome these common problems and discusses additional applications of the workflow including adaptations.
Collapse
Affiliation(s)
- Patrick Jung
- Department of Integrative Biotechnology, University of Applied Sciences Kaiserslautern, Pirmasens, Germany
| | - Laura Briegel-Williams
- Department of Integrative Biotechnology, University of Applied Sciences Kaiserslautern, Pirmasens, Germany
| | - Lina Werner
- Department of Integrative Biotechnology, University of Applied Sciences Kaiserslautern, Pirmasens, Germany
| | - Emily Jost
- Department of Integrative Biotechnology, University of Applied Sciences Kaiserslautern, Pirmasens, Germany
| | - Matthias Schultz
- Institute for Plant Science and Microbiology, Herbarium Hamburgense, University of Hamburg, Hamburg, Germany
| | - Dennis J. Nürnberg
- Institute of Experimental Physics, Freie Universität Berlin, Berlin, Germany
- Dahlem Centre for Plant Sciences, Freie Universität Berlin, Berlin, Germany
| | - Martin Grube
- Institute of Biology, University of Graz, Graz, Austria
| | - Michael Lakatos
- Department of Integrative Biotechnology, University of Applied Sciences Kaiserslautern, Pirmasens, Germany
| |
Collapse
|
2
|
Moore RA, Azua-Bustos A, González-Silva C, Carr CE. Unveiling metabolic pathways involved in the extreme desiccation tolerance of an Atacama cyanobacterium. Sci Rep 2023; 13:15767. [PMID: 37737281 PMCID: PMC10516996 DOI: 10.1038/s41598-023-41879-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2023] [Accepted: 09/01/2023] [Indexed: 09/23/2023] Open
Abstract
Gloeocapsopsis dulcis strain AAB1 is an extremely xerotolerant cyanobacterium isolated from the Atacama Desert (i.e., the driest and oldest desert on Earth) that holds astrobiological significance due to its ability to biosynthesize compatible solutes at ultra-low water activities. We sequenced and assembled the G. dulcis genome de novo using a combination of long- and short-read sequencing, which resulted in high-quality consensus sequences of the chromosome and two plasmids. We leveraged the G. dulcis genome to generate a genome-scale metabolic model (iGd895) to simulate growth in silico. iGd895 represents, to our knowledge, the first genome-scale metabolic reconstruction developed for an extremely xerotolerant cyanobacterium. The model's predictive capability was assessed by comparing the in silico growth rate with in vitro growth rates of G. dulcis, in addition to the synthesis of trehalose. iGd895 allowed us to explore simulations of key metabolic processes such as essential pathways for water-stress tolerance, and significant alterations to reaction flux distribution and metabolic network reorganization resulting from water limitation. Our study provides insights into the potential metabolic strategies employed by G. dulcis, emphasizing the crucial roles of compatible solutes, metabolic water, energy conservation, and the precise regulation of reaction rates in their adaptation to water stress.
Collapse
Affiliation(s)
- Rachel A Moore
- School of Earth and Atmospheric Sciences, Georgia Institute of Technology, 275 Ferst Dr. NW, Atlanta, GA, 30332, USA.
| | - Armando Azua-Bustos
- Centro de Astrobiología (CSIC-INTA), Madrid, Spain
- Instituto de Ciencias Biomédicas, Facultad de Ciencias de la Salud, Universidad Autónoma de Chile, Santiago, Chile
| | | | - Christopher E Carr
- School of Earth and Atmospheric Sciences, Georgia Institute of Technology, 275 Ferst Dr. NW, Atlanta, GA, 30332, USA
- Daniel Guggenheim School of Aerospace Engineering, Georgia Institute of Technology, Atlanta, GA, 30332, USA
| |
Collapse
|
3
|
Strunecký O, Ivanova AP, Mareš J. An updated classification of cyanobacterial orders and families based on phylogenomic and polyphasic analysis. JOURNAL OF PHYCOLOGY 2023; 59:12-51. [PMID: 36443823 DOI: 10.1111/jpy.13304] [Citation(s) in RCA: 36] [Impact Index Per Article: 36.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Accepted: 11/16/2022] [Indexed: 06/15/2023]
Abstract
Cyanobacterial taxonomy is facing a period of rapid changes thanks to the ease of 16S rRNA gene sequencing and established workflows for description of new taxa. Since the last comprehensive review of the cyanobacterial system in 2014 until 2021, at least 273 species in 140 genera were newly described. These taxa were mainly placed into previously defined orders and families although several new families were proposed. However, the classification of most taxa still relied on hierarchical relationships inherited from the classical morphological taxonomy. Similarly, the obviously polyphyletic orders such as Synechococcales and Oscillatoriales were left unchanged. In this study, the rising number of genomic sequences of cyanobacteria and well-described reference strains allowed us to reconstruct a robust phylogenomic tree for taxonomic purposes. A less robust but better sampled 16S rRNA gene phylogeny was mapped to the phylogenomic backbone. Based on both these phylogenies, a polyphasic classification throughout the whole phylum of Cyanobacteria was created, with ten new orders and fifteen new families. The proposed system of cyanobacterial orders and families relied on a phylogenomic tree but still employed phenotypic apomorphies where possible to make it useful for professionals in the field. It was, however, confirmed that morphological convergence of phylogenetically distant taxa was a frequent phenomenon in cyanobacteria. Moreover, the limited phylogenetic informativeness of the 16S rRNA gene, resulting in ambiguous phylogenies above the genus level, emphasized the integration of genomic data as a prerequisite for the conclusive taxonomic placement of a vast number of cyanobacterial genera in the future.
Collapse
Affiliation(s)
- Otakar Strunecký
- Faculty of Fisheries and Protection of Waters, CENAKVA, Institute of Aquaculture and Protection of Waters, University of South Bohemia in České Budějovice, Na Sádkách 1780, 370 05, České Budějovice, Czech Republic
| | - Anna Pavlovna Ivanova
- Faculty of Fisheries and Protection of Waters, CENAKVA, Institute of Aquaculture and Protection of Waters, University of South Bohemia in České Budějovice, Na Sádkách 1780, 370 05, České Budějovice, Czech Republic
| | - Jan Mareš
- Biology Centre of the CAS, Institute of Hydrobiology, Na Sádkách 702/7, 370 05, České Budějovice, Czech Republic
- Faculty of Science, Department of Botany, University of South Bohemia, Branišovská 1760, 370 05, České Budějovice, Czech Republic
| |
Collapse
|
4
|
Jung P, Brust K, Schultz M, Büdel B, Donner A, Lakatos M. Opening the Gap: Rare Lichens With Rare Cyanobionts - Unexpected Cyanobiont Diversity in Cyanobacterial Lichens of the Order Lichinales. Front Microbiol 2021; 12:728378. [PMID: 34690969 PMCID: PMC8527099 DOI: 10.3389/fmicb.2021.728378] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2021] [Accepted: 08/25/2021] [Indexed: 11/13/2022] Open
Abstract
The last decades of research led to a change in understanding of lichens that are now seen as self-sustaining micro-ecosystems, harboring diverse microbial organisms in tight but yet not fully understood relationships. Among the diverse interdependencies, the relationship between the myco- and photobiont is the most crucial, determining the shape, and ecophysiological properties of the symbiotic consortium. Roughly 10% of lichens associate with cyanobacteria as their primary photobiont, termed cyanolichens. Up to now, the diversity of cyanobionts of bipartite lichens resolved by modern phylogenetic approaches is restricted to the filamentous and heterocytous genera of the order Nostocales. Unicellular photobionts were placed in the orders Chroococcales, Pleurocapsales, and Chroococcidiopsidales. However, especially the phylogeny and taxonomy of the Chroococcidiopsidales genera remained rather unclear. Here we present new data on the identity and phylogeny of photobionts from cyanolichens of the genera Gonohymenia, Lichinella, Peccania, and Peltula from a broad geographical range. A polyphasic approach was used, combining morphological and cultivation-depending characteristics (microscopy, staining techniques, life cycle observation, baeocyte motility, and nitrogen fixation test) with phylogenetic analyses of the 16S rRNA and 16S–23S ITS gene region. We found an unexpectedly high cyanobiont diversity in the cyanobacterial lichens of the order Lichinales, including two new genera and seven new species, all of which were not previously perceived as lichen symbionts. As a result, we describe the novel unicellular Chroococcidiopsidales genera Pseudocyanosarcina gen. nov. with the species Pseudocyanosarcina phycocyania sp. nov. (from Peltula clavata, Australia) and Compactococcus gen. nov. with the species Compactococcus sarcinoides sp. nov. (from Gonohymenia sp., Australia) and the new Chroococcidiopsidales species Aliterella compacta sp. nov. (from Peltula clavata, Australia), Aliterella gigantea sp. nov. (from Peltula capensis; South Africa), Sinocapsa ellipsoidea sp. nov. (from Peccania cerebriformis, Austria), as well as the two new Nostocales species Komarekiella gloeocapsoidea sp. nov. (from Gonohymenia sp., Czechia) and Komarekiella globosa sp. nov. (from Lichinella cribellifera, Canary Islands, Spain). Our study highlights the role of cyanolichens acting as a key in untangling cyanobacterial taxonomy and diversity. With this study, we hope to stimulate further research on photobionts, especially of rare cyanolichens.
Collapse
Affiliation(s)
- Patrick Jung
- Department of Integrative Biotechnology, University of Applied Sciences Kaiserslautern, Pirmasens, Germany
| | - Katharina Brust
- Ecology Group, Faculty of Biology, University of Kaiserslautern, Kaiserslautern, Germany
| | - Matthias Schultz
- Institute for Plant Science and Microbiology, Herbarium Hamburgense, University of Hamburg, Hamburg, Germany
| | - Burkhard Büdel
- Faculty of Biology, University of Kaiserslautern, Kaiserslautern, Germany
| | - Antje Donner
- Faculty of Biology, University of Kaiserslautern, Kaiserslautern, Germany
| | - Michael Lakatos
- Department of Integrative Biotechnology, University of Applied Sciences Kaiserslautern, Pirmasens, Germany
| |
Collapse
|
5
|
Jung P, D’Agostino PM, Brust K, Büdel B, Lakatos M. Final Destination? Pinpointing Hyella disjuncta sp. nov. PCC 6712 (Cyanobacteria) Based on Taxonomic Aspects, Multicellularity, Nitrogen Fixation and Biosynthetic Gene Clusters. Life (Basel) 2021; 11:916. [PMID: 34575065 PMCID: PMC8472315 DOI: 10.3390/life11090916] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Revised: 08/25/2021] [Accepted: 08/30/2021] [Indexed: 11/16/2022] Open
Abstract
Unicellular cyanobacteria inhabit a wide range of ecosytems and can be found throughout the phylum offering space for taxonomic confusion. One example is strain PCC 6712 that was described as Chlorogloea sp. (Nostocales) and later assigned to the genus Chroococcidiopsis (Chroococcidiopsidales). We now show that this strain belongs to the order Pleurocapsales and term it Hyella disjuncta based on morphology, genome analyses and 16S-23S ITS rRNA phylogeny. Genomic analysis indicated that H. disjuncta PCC 6712 shared about 44.7% orthologue genes with its closest relative H. patelloides. Furthermore, 12 cryptic biosynthetic gene clusters (BGCs) with potential bioactivity, such as a mycosporine-like amino acid BGC, were detected. Interestingly, the full set of nitrogen fixation genes was found in H. disjuncta PCC 6712 despite its inability to grow on nitrogen-free medium. A comparison of genes responsible for multicellularity was performed, indicating that most of these genes were present and related to those found in other cyanobacterial orders. This is in contrast to the formation of pseudofilaments-a main feature of the genus Hyella-which is weakly expressed in H. disjuncta PCC 6712 but prominent in Hyella patelloides LEGE 07179. Thus, our study pinpoints crucial but hidden aspects of polyphasic cyanobacterial taxonomy.
Collapse
Affiliation(s)
- Patrick Jung
- Department of Integrative Biotechnology, University of Applied Sciences Kaiserslautern, Carl-Schurz-Str. 10–16, 66953 Pirmasens, Germany;
| | - Paul M. D’Agostino
- Department of Technical Biochemistry, Technical University of Dresden, Bergstr. 66, 01069 Dresden, Germany;
| | - Katharina Brust
- Department of Ecology, University of Kaiserslautern, Erwin Schrödinger Str. 14, 67663 Kaiserslautern, Germany;
| | - Burkhard Büdel
- Department of Plant Ecology and Systematics, University of Kaiserslautern, Erwin-Schrödinger Str. 52, 67663 Kaiserslautern, Germany;
| | - Michael Lakatos
- Department of Integrative Biotechnology, University of Applied Sciences Kaiserslautern, Carl-Schurz-Str. 10–16, 66953 Pirmasens, Germany;
| |
Collapse
|