ijms-logo

Journal Browser

Journal Browser

Molecular and Ecological Genetics of Microbial Metal Resistance

A special issue of International Journal of Molecular Sciences (ISSN 1422-0067). This special issue belongs to the section "Molecular Microbiology".

Deadline for manuscript submissions: closed (31 October 2020) | Viewed by 8906

Special Issue Editors


E-Mail Website
Guest Editor
Department of Biology, University of Florence, Via Madonna del Piano 6, 50019 Sesto Fiorentino, Italy
Interests: rhizospheric and endophytic microbiomes; microbial evolution; bacterial genetics and ecology
Special Issues, Collections and Topics in MDPI journals

E-Mail Website
Guest Editor
Department of Biology, University of Florence, Via Madonna del Piano 6, 50019 Sesto Fiorentino, Italy
Interests: plant–rhizobium symbiosis; systems biology; multipartite genomes; metagenomics; bacterial epigenomics
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

Microbes (bacteria, archaea, and eukaryotic microorganisms) develop metal resistance in a variety of environments, both natural and anthropogenic. Metal resistance microbial strains are routinely isolated from natural metal ion rich environments on the planet, as well as metal polluted sites from mining/refining/manufacturing operations. Studies on metal resistant microbes have constituted models for understanding the processes of the adaptation and evolution of microbial populations and communities. Moreover, metals constitute the basis of various antimicrobial agents, as well as one of the most important polluting agents in urbanized areas and in some agricultural areas. The molecular aspects of metal ion resistance span from single gene to integrated genome-wide (cellular) response, which give rise to possibly unique physiologies and multimetal resistance. Biotechnological applications of the findings derived from ecological and molecular investigations are also relevant, especially in the field of bioremediation.

This Special Issue is aimed at promoting research showing novel findings, and addressing the challenges along the interface between the molecular and ecological aspects of metal resistance in microorganisms.

Prof. Dr. Alessio Mengoni
Dr. Camilla Fagorzi
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. International Journal of Molecular Sciences is an international peer-reviewed open access semimonthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. There is an Article Processing Charge (APC) for publication in this open access journal. For details about the APC please see here. Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • bacteria
  • archaea
  • microorganisms
  • heavy metals
  • metalloids
  • metal resistance genes
  • metal resistance determinants
  • adaptation
  • evolution
  • microbiome
  • microbiota

Published Papers (3 papers)

Order results
Result details
Select all
Export citation of selected articles as:

Research

16 pages, 844 KiB  
Article
Genetic Carriers and Genomic Distribution of cadA6—A Novel Variant of a Cadmium Resistance Determinant Identified in Listeria spp.
by Cora Chmielowska, Dorota Korsak, Barbara Szmulkowska, Alicja Krop, Kinga Lipka, Martyna Krupińska and Dariusz Bartosik
Int. J. Mol. Sci. 2020, 21(22), 8713; https://0-doi-org.brum.beds.ac.uk/10.3390/ijms21228713 - 18 Nov 2020
Cited by 5 | Viewed by 2504
Abstract
Listeria monocytogenes is a pathogen responsible for severe cases of food poisoning. Listeria spp. strains occurring in soil and water environments may serve as a reservoir of resistance determinants for pathogenic L. monocytogenes strains. A large collection of Listeria spp. strains (155) isolated [...] Read more.
Listeria monocytogenes is a pathogen responsible for severe cases of food poisoning. Listeria spp. strains occurring in soil and water environments may serve as a reservoir of resistance determinants for pathogenic L. monocytogenes strains. A large collection of Listeria spp. strains (155) isolated from natural, agricultural, and urban areas was screened for resistance to heavy metals and metalloids, and the presence of resistance determinants and extrachromosomal replicons. Of the tested strains, 35% were resistant to cadmium and 17% to arsenic. Sequence analysis of resistance plasmids isolated from strains of Listeria seeligeri and Listeria ivanovii, and the chromosome of L. seeligeri strain Sr73, identified a novel variant of the cadAC cadmium resistance efflux system, cadA6, that was functional in L. monocytogenes cells. The cadA6 cassette was detected in four Listeria species, including strains of L. monocytogenes, isolated from various countries and sources—environmental, food-associated, and clinical samples. This resistance cassette is harbored by four novel composite or non-composite transposons, which increases its potential for horizontal transmission. Since some cadAC cassettes may influence virulence and biofilm formation, it is important to monitor their presence in Listeria spp. strains inhabiting different environments. Full article
(This article belongs to the Special Issue Molecular and Ecological Genetics of Microbial Metal Resistance)
Show Figures

Figure 1

21 pages, 6351 KiB  
Article
Multifunctional Periphytic Biofilms: Polyethylene Degradation and Cd2+ and Pb2+ Bioremediation under High Methane Scenario
by Muhammad Faheem, Sadaf Shabbir, Jun Zhao, Philip G. Kerr, Shafaqat Ali, Nasrin Sultana and Zhongjun Jia
Int. J. Mol. Sci. 2020, 21(15), 5331; https://0-doi-org.brum.beds.ac.uk/10.3390/ijms21155331 - 27 Jul 2020
Cited by 18 | Viewed by 2951
Abstract
Priority pollutants such as polyethylene (PE) microplastic, lead (Pb2+), and cadmium (Cd2+) have attracted the interest of environmentalists due to their ubiquitous nature and toxicity to all forms of life. In this study, periphytic biofilms (epiphyton and epixylon) were [...] Read more.
Priority pollutants such as polyethylene (PE) microplastic, lead (Pb2+), and cadmium (Cd2+) have attracted the interest of environmentalists due to their ubiquitous nature and toxicity to all forms of life. In this study, periphytic biofilms (epiphyton and epixylon) were used to bioremediate heavy metals (HMs) and to biodegrade PE under high (120,000 ppm) methane (CH4) doses. Both periphytic biofilms were actively involved in methane oxidation, HMs accumulation and PE degradation. Epiphyton and epixylon both completely removed Pb2+ and Cd2+ at concentrations of 2 mg L−1 and 50 mg L−1, respectively, but only partially removed these HMs at a relatively higher concentration (100 mg L−1). Treatment containing 12% 13CH4 proved to be most effective for biodegradation of PE. A synergistic effect of HMs and PE drastically changed microbial biota and methanotrophic communities. High-throughput 16S rRNA gene sequencing revealed that Cyanobacteria was the most abundant class, followed by Gammaproteobacteria and Alphaproteobacteria in all high-methane-dose treatments. DNA stable-isotope probing was used to label 13C in a methanotrophic community. A biomarker for methane-oxidizing bacteria, pmoA gene sequence of a 13C-labeled fraction, revealed that Methylobacter was most abundant in all high-methane-dose treatments compared to near atmospheric methane (NAM) treatment, followed by Methylococcus. Methylomonas, Methylocystis, Methylosinus, and Methylocella were also found to be increased by high doses of methane compared to NAM treatment. Overall, Cd+2 had a more determinantal effect on methanotrophic activity than Pb2+. Epiphyton proved to be more effective than epixylon in HMs removal and PE biodegradation. The findings proved that both epiphyton and epixylon can be used to bioremediate HMs and biodegrade PE as an efficient ecofriendly technique under high methane concentrations. Full article
(This article belongs to the Special Issue Molecular and Ecological Genetics of Microbial Metal Resistance)
Show Figures

Graphical abstract

22 pages, 3148 KiB  
Article
The Role of Zinc in Gliotoxin Biosynthesis of Aspergillus fumigatus
by Hyewon Seo, Suzie Kang, Yong-Sung Park and Cheol-Won Yun
Int. J. Mol. Sci. 2019, 20(24), 6192; https://0-doi-org.brum.beds.ac.uk/10.3390/ijms20246192 - 08 Dec 2019
Cited by 27 | Viewed by 2972
Abstract
Zinc performs diverse physiological functions, and virtually all living organisms require zinc as an essential trace element. To identify the detailed function of zinc in fungal pathogenicity, we carried out cDNA microarray analysis using the model system of Aspergillus fumigatus, a fungal [...] Read more.
Zinc performs diverse physiological functions, and virtually all living organisms require zinc as an essential trace element. To identify the detailed function of zinc in fungal pathogenicity, we carried out cDNA microarray analysis using the model system of Aspergillus fumigatus, a fungal pathogen. From microarray analysis, we found that the genes involved in gliotoxin biosynthesis were upregulated when zinc was depleted, and the microarray data were confirmed by northern blot analysis. In particular, zinc deficiency upregulated the expression of GliZ, which encodes a Zn2-Cys6 binuclear transcription factor that regulates the expression of the genes required for gliotoxin biosynthesis. The production of gliotoxin was decreased in a manner inversely proportional to the zinc concentration, and the same result was investigated in the absence of ZafA, which is a zinc-dependent transcription activator. Interestingly, we found two conserved ZafA-binding motifs, 5′-CAAGGT-3′, in the upstream region of GliZ on the genome and discovered that deletion of the ZafA-binding motifs resulted in loss of ZafA-binding activity; gliotoxin production was decreased dramatically, as demonstrated with a GliZ deletion mutant. Furthermore, mutation of the ZafA-binding motifs resulted in an increase in the conidial killing activity of human macrophage and neutrophil cells, and virulence was decreased in a murine model. Finally, transcriptomic analysis revealed that the expression of ZafA and GliZ was upregulated during phagocytosis by macrophages. Taken together, these results suggest that zinc plays an important role in the pathogenicity of A. fumigatus by regulating gliotoxin production during the phagocytosis pathway to overcome the host defense system. Full article
(This article belongs to the Special Issue Molecular and Ecological Genetics of Microbial Metal Resistance)
Show Figures

Figure 1

Back to TopTop