Evidence for the transport of zinc(II) ions via the Pit inorganic phosphate transport system in Escherichia coli

Beard, Steven J.

doi:10.1016/s0378-1097(00)00055-0

Cited by 42 publications

(60 citation statements)

References 27 publications

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“…Because double mutant analysis revealed that strains lacking both Znu and Zev pathways are not completely inhibited for growth in rich medium, it is likely that an additional pathway is involved in zinc acquisition of this organism. One possibility is the PitA-dependent inorganic phosphate utilization pathway, which was proposed to be a low-affinity zinc transporter of E. coli (6). Wholegenome mutant fitness analysis via HITS suggested that PitA is required for optimal growth in vitro as well as for lung infection (22).…”

Section: Discussionmentioning

confidence: 99%

A Novel Zinc Binding System, ZevAB, Is Critical for Survival of Nontypeable Haemophilus influenzae in a Murine Lung Infection Model

et al. 2011

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Nontypeable Haemophilus influenzae (NTHI) is a Gram-negative bacterial pathogen that causes upper and lower respiratory infections. Factors required for pulmonary infection by NTHI are not well understood. Previously, using high-throughput insertion tracking by deep sequencing (HITS), putative lung colonization factors were identified. Also, previous research indicates that secreted disulfide-dependent factors are important for virulence of H. influenzae. In the present study, HITS data were compared with an informatics-based list of putative substrates of the periplasmic oxidoreductase DsbA to find and characterize secreted virulence factors. This analysis resulted in identification of the "zinc binding essential for virulence" (zev) locus consisting of zevA (HI1249) and zevB (HI1248). NTHI mutants of zevA and zevB grew normally in rich medium but were defective for colonization in a mouse lung model. Mutants also exhibited severe growth defects in medium containing EDTA and were rescued by supplementation with zinc. Additionally, purified recombinant ZevA was found to bind to zinc with high affinity. Together, these data demonstrate that zevAB is a novel virulence factor important for zinc utilization of H. influenzae under conditions where zinc is limiting. Furthermore, evidence presented here suggests that zinc limitation is likely an important mechanism for host defense against pathogens during lung infection.

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Section: Discussionmentioning

confidence: 99%

A Novel Zinc Binding System, ZevAB, Is Critical for Survival of Nontypeable Haemophilus influenzae in a Murine Lung Infection Model

et al. 2011

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“…Some zinc transport systems have been studied in prokaryotes such as Enterobacteriaceae, Pseudomonadaceae, Neisseriaceae and Pasteurellaceae, among others [3,8,16,17]. Escherichia coli cells present two independent systems to zinc uptake encoding znuABC and pitA genes, respectively [2,17]. E. coli znuA and znuCB operons (encoding a periplasmic-binding protein, an ATPase and an integral membrane protein, respectively) are divergently oriented, and their transcriptional starting points are separated by 24 bp [17].…”

Section: Discussionmentioning

confidence: 99%

“…In Eschrerichia coli, two systems, a high-affinity system and a low-affinity system, have been described for zinc uptake [2,17], and the high-affinity zinc uptake system of Salmonella enterica serovar Typhimurium is important for virulence in mouse model [3]. However, B. abortus does not contain low-affinity zinc uptake system [6] and high-affinity zinc uptake system is still not understood.…”

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confidence: 99%

Zinc Uptake System (znuA Locus) of Brucella abortus is Essential for Intracellular Survival and Virulence in Mice

Kim

Watanabe

Shirahata

et al. 2004

The Journal of Veterinary Medical Science

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ABSTRACT. Brucella spp. are facultative intracellular pathogens that have the ability to survive and multiply in professional and nonprofessional phagocytes, and cause abortion in domestic animals and undulant fever in humans. The mechanism and factors of virulence are not fully understood. High-affinity zinc uptake system protein mutant (znuA mutant) showed reduced growth in zinc chelated medium, and failed to replicate in HeLa cells and mouse bone marrow-derived macrophages. Transformation of znuA mutant with a shuttle vector pBBR1MCS-4 containing znuA gene restored the growth in zinc chelated medium and intracellular replication in HeLa cells and macrophages to a level comparable to that of wild-type strain. Bacterial internalization into HeLa cells and macrophages and co-localization with either late endosomes or lysosomes of znuA mutant were not different from those of wild-type strain. These results suggest that znuA does not contribute to intracellular trafficking of B. abortus, but contributes to utilization of zinc required for intracellular growth. KEY WORDS: Brucella abortus, intracellular growth, zinc, znuA.J. Vet. Med. Sci. 66(9): 1059-1063, 2004 Brucella abortus, a facultative, gram-negative, intracellular pathogen, is the etiologic agent of brucellosis, a widely distributed zoonosis [22]. The establishment of chronic infection depends on the ability of brucellae to survive within phagocytes [9]. In contrast to other intracellular pathogens, Brucella species do not produce exotoxins, antiphagocytic capsules or thick cell walls, resistance forms or fimbriae and do not show antigenic variation [7]. Intracellular survival and replication are key virulence features of Brucella because mutants defective for these attributes are also avirulent [10,14]. A key aspect of the virulence of Brucella successfully bypasses the bactericidal effects of phagocytes, and their virulence and chronic infections are thought to be due to their ability to avoid the killing mechanisms within host cells [5,20].The genetic basis of Brucella virulence is still poorly understood. The VirB type IV secretion system of Brucella has been identified recently [16]. This operon is composed of 13 open reading frames (ORFs) that share homology with other bacterial type IV secretion systems in the intracellular trafficking of pathogens. Deletion or polar and non-polar mutations of these ORFs were not able to replicate and survive within phagocytes [19,21], and internalization and uptake pathway in phagosome trafficking between wildtype and virB mutant showed different patterns [11]. Thus, the VirB proteins of B. abortus are thought to be constituents of the secretion apparatus. The genus Brucella does not contain plasmids naturally, and it is therefore possible that the proteins encoded by virB genes are involved in protein secretion rather than conjugation. A possible role in virulence is to inject effector molecules, which help in the establishment of replication niche into the host cell.Zinc plays an important role in living organism...

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“…For determination of the affinity constants Km and K0.5 for Pi, oocytes were incubated for 5 min in uptake solution containing KH 2 32 PO4 in concentrations varying from 1,000 to 7.8 M. For determination of the pH-dependent Na 32 Pi uptake pattern, oocytes were incubated for 1 h in uptake solutions modified to reach pH values ranging from 4.5 to 5.5 and 6.5 with HCl and to 8.5 with KOH. More acidic conditions could not be analyzed because the oocytes did not tolerate pH 3.5.…”

Section: Methodsmentioning

confidence: 99%

Characterization of transport mechanisms and determinants critical for Na⁺-dependent P_i symport of the PiT family paralogs human PiT1 and PiT2

Bøttger

Hede²,

Grunnet³

et al. 2006

American Journal of Physiology-Cell Physiology

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Evidence for the transport of zinc(II) ions via the Pit inorganic phosphate transport system in Escherichia coli

Cited by 42 publications

References 27 publications

A Novel Zinc Binding System, ZevAB, Is Critical for Survival of Nontypeable Haemophilus influenzae in a Murine Lung Infection Model

A Novel Zinc Binding System, ZevAB, Is Critical for Survival of Nontypeable Haemophilus influenzae in a Murine Lung Infection Model

Zinc Uptake System (znuA Locus) of Brucella abortus is Essential for Intracellular Survival and Virulence in Mice

Characterization of transport mechanisms and determinants critical for Na⁺-dependent P_i symport of the PiT family paralogs human PiT1 and PiT2

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Evidence for the transport of zinc(II) ions via the Pit inorganic phosphate transport system in Escherichia coli

Cited by 42 publications

References 27 publications

A Novel Zinc Binding System, ZevAB, Is Critical for Survival of Nontypeable Haemophilus influenzae in a Murine Lung Infection Model

A Novel Zinc Binding System, ZevAB, Is Critical for Survival of Nontypeable Haemophilus influenzae in a Murine Lung Infection Model

Zinc Uptake System (znuA Locus) of Brucella abortus is Essential for Intracellular Survival and Virulence in Mice

Characterization of transport mechanisms and determinants critical for Na+-dependent Pi symport of the PiT family paralogs human PiT1 and PiT2

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Characterization of transport mechanisms and determinants critical for Na⁺-dependent P_i symport of the PiT family paralogs human PiT1 and PiT2