Crystal Structure and Metal-Binding Specificity of ZneB, the Periplasmic Adaptor Protein of A Heavy Metal Resistance System from Cupriavidus Metallidurans CH34

Cadmium is a highly toxic heavy metal for biological systems. Cupriavidus metallidurans CH34 is a model strain for heavy metal resistance and bioremediation. The aim of this study was to determine the role of the c-di-GMP pathway in the C. metallidurans CH34 response to cadmium in both planktonic and biofilm cells. Increasing cadmium concentrations correlates with an inhibition of biofilm formation and EPS production in C. metallidurans cells. Planktonic and biofilm cells showed similar tolerance to cadmium. During exposure to cadmium an acute decrease of c-di-GMP levels in planktonic and biofilm cells was observed. Transcription analysis by RT-qPCR showed that cadmium induced in planktonic cells and strongly induced in biofilm cells the expression of the urf2 gene and the mercuric reductase encoding merA gene, which belong to the Tn501/Tn21 mer operon. After exposure to cadmium the cadA gene involved in cadmium resistance was equally upregulated in both lifestyles. Bioinformatic analysis and null mutant complementation assays indicated that the protein encoded by the urf2 gene is a functional phosphodiesterase involved in the c-di-GMP metabolism. We propose to rename the urf2 gene as mrp gene for metal regulated phosphodiesterase. An increase of the second messenger c-di-GMP content by the heterologous expression of the constitutively active diguanylate cyclase PleD* correlated with an increase in biofilm formation and cadmium susceptibility. These results indicate that the response to cadmium in C. metallidurans CH34 involves a decrease in c-di-GMP content that inhibits the biofilm lifestyle.

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Heavy metal resistance in Cupriavidus metallidurans CH34 is governed by an intricate transcriptional network

BioMetals ◽

10.1007/s10534-011-9473-y ◽

2011 ◽

Vol 24 (6) ◽

pp. 1133-1151 ◽

Cited By ~ 72

Author(s):

Pieter Monsieurs ◽

Hugo Moors ◽

Rob Van Houdt ◽

Paul J. Janssen ◽

Ann Janssen ◽

...

Keyword(s):

Heavy Metal ◽

Heavy Metal Resistance ◽

Metal Resistance ◽

Transcriptional Network ◽

Cupriavidus Metallidurans Ch34 ◽

Cupriavidus Metallidurans

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Bioinformatic analysis of the metal-binding protein families and heavy metal resistance amongst cyanobacteria

Proceedings of 2005 International Conference on Intelligent Sensing and Information Processing, 2005. ◽

10.1109/icisip.2005.1529507 ◽

2005 ◽

Author(s):

Tin-Chun Chu ◽

L.H. Lee ◽

S. Srinivasan

Keyword(s):

Heavy Metal ◽

Metal Binding ◽

Binding Protein ◽

Bioinformatic Analysis ◽

Heavy Metal Resistance ◽

Metal Resistance ◽

Protein Families ◽

Metal Binding Protein

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Identification of a regulatory pathway that controls the heavy-metal resistance system Czc via promoter czcNp in Ralstonia metallidurans

Archives of Microbiology ◽

10.1007/s00203-004-0670-8 ◽

2004 ◽

Vol 182 (2-3) ◽

Cited By ~ 28

Author(s):

Cornelia Gro�e ◽

Andreas Anton ◽

Toni Hoffmann ◽

Sylvia Franke ◽

Grit Schleuder ◽

...

Keyword(s):

Heavy Metal ◽

Heavy Metal Resistance ◽

Metal Resistance ◽

Regulatory Pathway ◽

Resistance System ◽

Ralstonia Metallidurans

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Plasmids pMOL28 and pMOL30 of Cupriavidus metallidurans Are Specialized in the Maximal Viable Response to Heavy Metals

Journal of Bacteriology ◽

10.1128/jb.00375-07 ◽

2007 ◽

Vol 189 (20) ◽

pp. 7417-7425 ◽

Cited By ~ 158

Author(s):

Sébastien Monchy ◽

Mohammed A. Benotmane ◽

Paul Janssen ◽

Tatiana Vallaeys ◽

Safiyh Taghavi ◽

...

Keyword(s):

Heavy Metals ◽

Heavy Metal ◽

Heavy Metal Stress ◽

Heavy Metal Resistance ◽

Metal Resistance ◽

Genomic Islands ◽

Specific Response ◽

Resistance Proteins ◽

Cupriavidus Metallidurans ◽

General Response

ABSTRACT We fully annotated two large plasmids, pMOL28 (164 open reading frames [ORFs]; 171,459 bp) and pMOL30 (247 ORFs; 233,720 bp), in the genome of Cupriavidus metallidurans CH34. pMOL28 contains a backbone of maintenance and transfer genes resembling those found in plasmid pSym of C. taiwanensis and plasmid pHG1 of C. eutrophus, suggesting that they belong to a new class of plasmids. Genes involved in resistance to the heavy metals Co(II), Cr(VI), Hg(II), and Ni(II) are concentrated in a 34-kb region on pMOL28, and genes involved in resistance to Ag(I), Cd(II), Co(II), Cu(II), Hg(II), Pb(II), and Zn(II) occur in a 132-kb region on pMOL30. We identified three putative genomic islands containing metal resistance operons flanked by mobile genetic elements, one on pMOL28 and two on pMOL30. Transcriptomic analysis using quantitative PCR and microarrays revealed metal-mediated up-regulation of 83 genes on pMOL28 and 143 genes on pMOL30 that coded for all known heavy metal resistance proteins, some new heavy metal resistance proteins (czcJ, mmrQ, and pbrU), membrane proteins, truncated transposases, conjugative transfer proteins, and many unknown proteins. Five genes on each plasmid were down-regulated; for one of them, chrI localized on pMOL28, the down-regulation occurred in the presence of five cations. We observed multiple cross-responses (induction of specific metal resistance by other metals), suggesting that the cellular defense of C. metallidurans against heavy metal stress involves various regulons and probably has multiple stages, including a more general response and a more metal-specific response.

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Genomic Islands Confer Heavy Metal Resistance in Mucilaginibacter kameinonensis and Mucilaginibacter rubeus Isolated from a Gold/Copper Mine

Genes ◽

10.3390/genes9120573 ◽

2018 ◽

Vol 9 (12) ◽

pp. 573 ◽

Cited By ~ 3

Author(s):

Yuan Li ◽

Nicolas Carraro ◽

Nan Yang ◽

Bixiu Liu ◽

Xian Xia ◽

...

Keyword(s):

Heavy Metals ◽

Heavy Metal ◽

Metal Binding ◽

Heavy Metal Resistance ◽

Metal Resistance ◽

Genomic Islands ◽

High Abundance ◽

Metal Transporter ◽

Genes Encoding ◽

Living Organisms

Heavy metals (HMs) are compounds that can be hazardous and impair growth of living organisms. Bacteria have evolved the capability not only to cope with heavy metals but also to detoxify polluted environments. Three heavy metal-resistant strains of Mucilaginibacer rubeus and one of Mucilaginibacter kameinonensis were isolated from the gold/copper Zijin mining site, Longyan, Fujian, China. These strains were shown to exhibit high resistance to heavy metals with minimal inhibitory concentration reaching up to 3.5 mM Cu(II), 21 mM Zn(II), 1.2 mM Cd(II), and 10.0 mM As(III). Genomes of the four strains were sequenced by Illumina. Sequence analyses revealed the presence of a high abundance of heavy metal resistance (HMR) determinants. One of the strain, M. rubeus P2, carried genes encoding 6 putative PIB-1-ATPase, 5 putative PIB-3-ATPase, 4 putative Zn(II)/Cd(II) PIB-4 type ATPase, and 16 putative resistance-nodulation-division (RND)-type metal transporter systems. Moreover, the four genomes contained a high abundance of genes coding for putative metal binding chaperones. Analysis of the close vicinity of these HMR determinants uncovered the presence of clusters of genes potentially associated with mobile genetic elements. These loci included genes coding for tyrosine recombinases (integrases) and subunits of mating pore (type 4 secretion system), respectively allowing integration/excision and conjugative transfer of numerous genomic islands. Further in silico analyses revealed that their genetic organization and gene products resemble the Bacteroides integrative and conjugative element CTnDOT. These results highlight the pivotal role of genomic islands in the acquisition and dissemination of adaptive traits, allowing for rapid adaption of bacteria and colonization of hostile environments.

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Genomic Islands Confer Heavy Metal Resistance in Mucilaginibacter Kameinonensis and Mucilaginibacter Rubeus Isolated from a Gold/Copper Mine

10.20944/preprints201810.0505.v1 ◽

2018 ◽

Author(s):

Yuan Ping Li ◽

Nicolas Carraro ◽

Nan Yang ◽

Bixiu Liu ◽

Xian Xia ◽

...

Keyword(s):

Heavy Metals ◽

Heavy Metal ◽

Metal Binding ◽

Heavy Metal Resistance ◽

Metal Resistance ◽

Genomic Islands ◽

High Abundance ◽

Metal Transporter ◽

Genes Encoding ◽

Living Organisms

Heavy metals are compounds that can be hazardous and impair growth of living organisms. Bacteria have evolved the capability not only to cope with heavy metals but also to detoxify polluted environments. Three heavy metal-resistant strains of Mucilaginibacer rubeus and one of Mucilaginibacter kameinonensis were isolated from the gold/copper Zijin mining site, Longyan, Fujian, China. These strains were shown to exhibit high resistance to heavy metals with minimal inhibitory concentration reaching up to 3.5 mM Cu(II), 21 mM Zn(II), 1.2 mM Cd(II), and 10.0 mM As(III). Genomes of the four strains were sequenced by Illumina. Sequence analyses revealed the presence of a high abundance of heavy metal resistance (HMR) determinants. One of the strain, M. rubeus P2, carried genes encoding 6 putative P1B-1-ATPase, 5 putative P1B-3-ATPase and 4 putative Zn(II)/Cd(II) P1B-4 type ATPase, and 16 putative RND-type metal transporter systems. Moreover, the four genomes carry a high abundance of genes coding for putative metal binding chaperones. Analysis of the close vicinity of these HMR determinants uncovered the presence of clusters of genes potentially associated with mobile genetic elements. These loci include genes coding for tyrosine recombinases (integrases) and subunits of mating pore (type 4 secretion system) respectively allowing integration/excision and conjugative transfer of numerous genomic islands. Further in silico analyses revealed that their genetic organization and gene products resemble the Bacteroides integrative and conjugative element CTnDOT. These results highlight the pivotal role of genomic islands in the acquisition and dissemination of adaptive traits, allowing for rapid adaption of bacteria and colonization of hostile environments.

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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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