Streptococcus agalactiaefrom pregnant women: antibiotic and heavy-metal resistance mechanisms and molecular typing

SUMMARYWe investigated the antibiotic and heavy-metal resistance mechanisms, virulence genes and clonal relationships of macrolide- and/or lincosamide-resistant (M+/−LR)Streptococcus agalactiae(group BStreptococcus, GBS) isolates from pregnant women in La Rioja in Northern Spain, a region with a significant immigrant population. In total 375 GBS isolates were recovered during 2011. About three-quarters of isolates were from European nationals and the remainder distributed among 23 other nationalities. Seventy-five (20%) were classified as M+/−LRstrains and 28 (37%) of these were resistant to ⩾3 classes of antibiotics. Capsular serotypes III (29·3%), V (21·3%) and II (12%) were the most frequent. A wide variety of antibiotic resistance genes were detected in M+/−LRstrains; notably, 5·3% harboured thelsa(C) gene associated with cross-resistance, andtet(W) was identified in a single strain. We report, for the first time, the detection of cadmium and copper resistance encoded bytcrB+cadA+cadCgenes in 20 M+/−LRstrains, which raises the possibility of co-selection of antibiotic and heavy-metal resistance disseminated through mobile genetic elements. The M+/−LRstrains were highly diverse by DNA macrorestriction profiles (65 patterns) and 16 multilocus sequence types (STs) distributed among six clonal complexes; the most frequent were ST1, ST19, and ST12, and two strains were novel (ST586 and ST601). In conclusion, a wide diversity of genetic lineages of macrolide, lincosamide and heavy-metal- resistant GBS strains was observed in an ethnically diverse maternal population.

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Heavy metal resistance mechanisms in actinobacteria for survival in AMD contaminated soils

Geochemistry ◽

10.1016/j.chemer.2005.06.006 ◽

2005 ◽

Vol 65 ◽

pp. 131-144 ◽

Cited By ~ 78

Author(s):

Andre Schmidt ◽

Götz Haferburg ◽

Manuel Sineriz ◽

Dirk Merten ◽

Georg Büchel ◽

...

Keyword(s):

Heavy Metal ◽

Contaminated Soils ◽

Heavy Metal Resistance ◽

Resistance Mechanisms ◽

Metal Resistance

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Co-selection of antibiotic and heavy metal resistance in freshwater bacteria

Journal of Limnology ◽

10.4081/jlimnol.2016.1198 ◽

2016 ◽

Vol 75 (s2) ◽

Cited By ~ 34

Author(s):

Andrea Di Cesare ◽

Ester Eckert ◽

Gianluca Corno

Keyword(s):

Heavy Metal ◽

Resistance Genes ◽

Heavy Metal Resistance ◽

Resistance Mechanisms ◽

Metal Resistance ◽

Resistant Bacteria ◽

Human Pathogens ◽

Antibiotic Resistant Bacteria ◽

Antibiotic Resistant ◽

Selection Of

Antibiotic resistant bacteria are found in most environments, especially in highly anthropized waters. A direct correlation between human activities (e.g., pollution) and spread and persistence of antibiotic resistant bacteria (ARB) and resistance genes (ARGs) within the resident bacterial communities appears more and more obvious. Furthermore, the threat posed for human health by the presence of ARB and ARGs in these environments is enhanced by the risk of horizontal gene transfer of resistance genes to human pathogens. Although the knowledge on the spread of antibiotic resistances in waters is increasing, the understanding of the driving factors determining the selection for antibiotic resistance in the environment is still scarce. Antibiotic pollution is generally coupled with contamination by heavy metals (HMs) and other chemicals, which can also promote the development of resistance mechanisms, often through co-selecting for multiple resistances. The co-selection of heavy metal resistance genes and ARGs in waters, sediments, and soils, increases the complexity of the ecological role of ARGs, and reduces the effectiveness of control actions. In this mini-review we present the state-of-the-art of the research on antibiotic- and HM-resistance and their connection in the environment, with a focus on HM pollution and aquatic environments. We review the spread and the persistence of HMs and/or ARB, and how it influences their respective gene co-selection. In the last chapter, we propose Lake Orta, a system characterized by an intensive HM pollution followed by a successful restoration of the chemistry of the water column, as a study-site to evaluate the spread and selection of HMs and antibiotic resistances in heavily disturbed environments.

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Microbial bioremediation of heavy metals

Hemijska industrija ◽

10.2298/hemind200915010v ◽

2021 ◽

Vol 75 (2) ◽

pp. 103-115

Author(s):

Ana Volaric ◽

Zorica Svircev ◽

Dragana Tamindzija ◽

Dragan Radnovic

Keyword(s):

Heavy Metals ◽

Heavy Metal ◽

Heavy Metal Resistance ◽

Pilot Scale ◽

Resistance Mechanisms ◽

Metal Resistance ◽

Novel Technologies ◽

Living Organisms ◽

Microbial Bioremediation ◽

Physical And Chemical

Heavy metal pollution is one of the most serious environmental problems, due to metal ions persistence, bioavailability, and toxicity. There are many conventional physical and chemical techniques traditionally used for environmental clean-up. Due to several drawbacks regarding these methods, the use of living organisms, or bioremediation, is becoming more prevalent. Biotechnological application of microorganisms is already successfully implemented and is in constant development, with many microbial strains successfully removing heavy metals. This paper provides an overview of the main heavy metal characteristics and describes the interactions with microorganisms. Key heavy metal resistance mechanisms in microorganisms are described, as well as the main principles and types of heavy metal bioremediation methods, with details on successful pilot scale bioreactor studies. Special attention should be given to indigenous bacteria isolated from the polluted environments since such species are already adapted to contamination and possess resistance mechanisms. Utilization of bacterial biofilms or consortia could be advantageous due to higher resistance and a combination of several metabolic pathways, and thus, the possibility to remove several heavy metals simultaneously. Novel technologies covered in this review, such as nanotechnology, genetic engineering, and metagenomics, are being introduced to the field of bioremediation in order to improve the process. To conclude, bioremediation is a potentially powerful solution for cleaning the environment.

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Heavy-metal resistance mechanisms developed by bacteria from Lerma–Chapala basin

Archives of Microbiology ◽

10.1007/s00203-020-02140-2 ◽

2021 ◽

Author(s):

Ivan Arroyo-Herrera ◽

Brenda Román-Ponce ◽

Ana Laura Reséndiz-Martínez ◽

Paulina Estrada-de los Santos ◽

En Tao Wang ◽

...

Keyword(s):

Heavy Metal ◽

Heavy Metal Resistance ◽

Resistance Mechanisms ◽

Metal Resistance

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Genomic analysis for heavy metal resistance in S. maltophilia

10.1101/404954 ◽

2018 ◽

Cited By ~ 2

Author(s):

Wenbang Yu ◽

Xiaoxiao Chen ◽

Yilin Sheng ◽

Qinghong Hong

Keyword(s):

Heavy Metal ◽

Gc Content ◽

Genomic Analysis ◽

Heavy Metal Resistance ◽

Resistance Mechanisms ◽

Metal Resistance ◽

Single Chromosome ◽

Ion Transporter ◽

Protein Encoding ◽

Mercury Detoxification

AbstractStenotrophomonas maltophilia is highly resistant to heavy metals, but the genetic knowledge of metal resistance in S. maltophilia is poorly understood. In this study, the genome of S.maltophilia Pho isolated from the contaminated soil near a metalwork factory was sequenced using PacBio RS II. Its genome is composed of a single chromosome with a GC content of 66.4% and 4434 protein-encoding genes. Comparative analysis revealed high syntney between S.maltophilia Pho and the model strain, S.maltophilia K279a. Then, the type and number of mechanisms for heavy metal uptake were analyzed firstly. Results revealed 7 unspecific ion transporter genes and 13 specific ion transporter genes, most of which were involved in iron transport. But the sulfate permeases belonging to the family of SulT/CysP that can uptake chromate and the high affinity ZnuABC/SitABCD were absent. Secondly, the putative genes controlling metal efflux were identified. Results showed that this bacterium encoded 5 CDFs, 1 copper exporting ATPase and 4 RND systems, including 2 CzcABC efflux pumps. Moreover, the putative metal transformation genes including arsenate and mercury detoxification genes were also identified. This study may provide useful information on the metal resistance mechanisms of S.maltophilia.

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Composition and Niche-Specific Characteristics of Microbial Consortia Colonizing Marsberg Copper Mine in the Rhenish Massif

10.5194/bg-2021-165 ◽

2021 ◽

Author(s):

Sania Arif ◽

Heiko Nacke ◽

Elias Schliekmann ◽

Andreas Reimer ◽

Gernot Arp ◽

...

Keyword(s):

Heavy Metal ◽

Heavy Metal Resistance ◽

Resistance Mechanisms ◽

Metal Resistance ◽

Microbial Consortia ◽

Rhenish Massif ◽

Copper Mine ◽

Alum Shale ◽

Heavy Metal Resistant ◽

Detoxification Pathways

Abstract. The Kilianstollen Marsberg (Rhenish Massif, Germany) has been extensively mined for copper ores, dating from Early Medieval Period till 1945. The exposed organic-rich alum shale rocks influenced by the diverse mine drainages at an ambient temperature of 10 °C could naturally enrich biogeochemically distinct heavy metal resistant microbiota. This metagenomic study evaluates the microbially colonized subterranean rocks of the abandoned copper mine Kilianstollen to characterize the colonization patterns and biogeochemical pathways of individual microbial groups. Under the selective pressure of the heavy metal contaminated environment at illuminated sites, Chloroflexi (Ktedonobacteria) and Cyanobacteria (Oxyphotobacteria) build up whitish-greenish biofilms. In contrast, Proteobacteria, Firmicutes and Actinobacteria dominate rocks around the uncontaminated spring water streams. The metagenomic analysis revealed that the heavy metal resistant microbiome was evidently involved in redox cycling of transition metals (Cu, Zn, Co, Ni, Mn, Fe, Cd, Hg). No deposition of metals or minerals, though, was observed by transmission electron microscopy in Ktedonobacteria biofilms which may be indicative for the presence of different detoxification pathways. The underlying heavy metal resistance mechanisms, as revealed by analysis of metagenome-assembled genomes, were mainly attributed to transition metal efflux pumps, redox enzymes, volatilization of Hg0, methylated intermediates of As(III) and reactive oxygen species detoxification pathways.

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Revealing taxon-specific heavy metal-resistance mechanisms in denitrifying phosphorus removal sludge using genome-centric metaproteomics

Microbiome ◽

10.1186/s40168-021-01016-x ◽

2021 ◽

Vol 9 (1) ◽

Author(s):

Yuan Lin ◽

Liye Wang ◽

Ke Xu ◽

Kan Li ◽

Hongqiang Ren

Keyword(s):

Heavy Metals ◽

Heavy Metal ◽

Phosphorus Removal ◽

Heavy Metal Resistance ◽

Resistance Mechanisms ◽

Metal Resistance ◽

Energy Utilization ◽

Nitrogen And Phosphorus ◽

Denitrifying Phosphorus Removal ◽

Metabolic Versatility

Abstract Background Denitrifying phosphorus removal sludge (DPRS) is widely adopted for nitrogen and phosphorus removal in wastewater treatment but faces threats from heavy metals. However, a lack of understanding of the taxon-specific heavy metal-resistance mechanisms hinders the targeted optimization of DPRS’s robustness in nutrient removal. Results We obtained 403 high- or medium-quality metagenome-assembled genomes from DPRS treated by elevating cadmium, nickel, and chromium pressure. Then, the proteomic responses of individual taxa under heavy metal pressures were characterized, with an emphasis on functions involving heavy metal resistance and maintenance of nutrient metabolism. When oxygen availability was constrained by high-concentration heavy metals, comammox Nitrospira overproduced highly oxygen-affinitive hemoglobin and electron-transporting cytochrome c-like proteins, underpinning its ability to enhance oxygen acquisition and utilization. In contrast, Nitrosomonas overexpressed ammonia monooxygenase and nitrite reductase to facilitate the partial nitrification and denitrification process for maintaining nitrogen removal. Comparisons between phosphorus-accumulating organisms (PAOs) demonstrated different heavy metal-resistance mechanisms adopted by Dechloromonas and Candidatus Accumulibacter, despite their high genomic similarities. In particular, Dechloromonas outcompeted the canonical PAO Candidatus Accumulibacter in synthesizing polyphosphate, a potential public good for heavy metal detoxification. The superiority of Dechloromonas in energy utilization, radical elimination, and damaged cell component repair also contributed to its dominance under heavy metal pressures. Moreover, the enrichment analysis revealed that functions involved in extracellular polymeric substance formation, siderophore activity, and heavy metal efflux were significantly overexpressed due to the related activities of specific taxa. Conclusions Our study demonstrates that heavy metal-resistance mechanisms within a multipartite community are highly heterogeneous between different taxa. These findings provide a fundamental understanding of how the heterogeneity of individual microorganisms contributes to the metabolic versatility and robustness of microbiomes inhabiting dynamic environments, which is vital for manipulating the adaptation of microbial assemblages under adverse environmental stimuli.

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Heavy Metal Tolerance Trend in Extended-Spectrum β-Lactamase Encoding Strains Recovered from Food Samples

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph18094718 ◽

2021 ◽

Vol 18 (9) ◽

pp. 4718

Author(s):

Kashaf Junaid ◽

Hasan Ejaz ◽

Iram Asim ◽

Sonia Younas ◽

Humaira Yasmeen ◽

...

Keyword(s):

Heavy Metal ◽

Metal Tolerance ◽

Heavy Metal Tolerance ◽

Heavy Metal Resistance ◽

Metal Resistance ◽

Food Samples ◽

Esbl Production ◽

Extended Spectrum ◽

Retail Food ◽

Esbl Producers

This study evaluates bacteriological profiles in ready-to-eat (RTE) foods and assesses antibiotic resistance, extended-spectrum β-lactamase (ESBL) production by gram-negative bacteria, and heavy metal tolerance. In total, 436 retail food samples were collected and cultured. The isolates were screened for ESBL production and molecular detection of ESBL-encoding genes. Furthermore, all isolates were evaluated for heavy metal tolerance. From 352 culture-positive samples, 406 g-negative bacteria were identified. Raw food samples were more often contaminated than refined food (84.71% vs. 76.32%). The predominant isolates were Klebsiella pneumoniae (n = 76), Enterobacter cloacae (n = 58), and Escherichia coli (n = 56). Overall, the percentage of ESBL producers was higher in raw food samples, although higher occurrences of ESBL-producing E. coli (p = 0.01) and Pseudomonas aeruginosa (p = 0.02) were observed in processed food samples. However, the prevalence of ESBL-producing Citrobacter freundii in raw food samples was high (p = 0.03). Among the isolates, 55% were blaCTX-M, 26% were blaSHV, and 19% were blaTEM. Notably, heavy metal resistance was highly prevalent in ESBL producers. These findings demonstrate that retail food samples are exposed to contaminants including antibiotics and heavy metals, endangering consumers.

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Genome-Driven Discovery of Enzymes with Industrial Implications from the Genus Aneurinibacillus

Microorganisms ◽

10.3390/microorganisms9030499 ◽

2021 ◽

Vol 9 (3) ◽

pp. 499

Author(s):

Majid Rasool Kamli ◽

Nada A. Y. Alzahrani ◽

Nahid H. Hajrah ◽

Jamal S. M. Sabir ◽

Adeel Malik

Keyword(s):

Heavy Metal ◽

Enzyme Activities ◽

Heavy Metal Resistance ◽

Industrial Applications ◽

Metal Resistance ◽

The Family ◽

Antiviral Activities ◽

Genome Level ◽

Genome Analyses ◽

Unique Species

Bacteria belonging to the genus Aneurinibacillus within the family Paenibacillaceae are Gram-positive, endospore-forming, and rod-shaped bacteria inhabiting diverse environments. Currently, there are eight validly described species of Aneurinibacillus; however, several unclassified species have also been reported. Aneurinibacillus spp. have shown the potential for producing secondary metabolites (SMs) and demonstrated diverse types of enzyme activities. These features make them promising candidates with industrial implications. At present, genomes of 9 unique species from the genus Aneurinibacillus are available, which can be utilized to decipher invaluable information on their biosynthetic potential as well as enzyme activities. In this work, we performed the comparative genome analyses of nine Aneurinibacillus species representing the first such comprehensive study of this genus at the genome level. We focused on discovering the biosynthetic, biodegradation, and heavy metal resistance potential of this under-investigated genus. The results indicate that the genomes of Aneurinibacillus contain SM-producing regions with diverse bioactivities, including antimicrobial and antiviral activities. Several carbohydrate-active enzymes (CAZymes) and genes involved in heavy metal resistance were also identified. Additionally, a broad range of enzyme classes were also identified in the Aneurinibacillus pan-genomes, making this group of bacteria potential candidates for future investigations with industrial applications.

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