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  1. Article ; Online: Architecture, Function, and Substrates of the Type II Secretion System.

    Korotkov, Konstantin V / Sandkvist, Maria

    EcoSal Plus

    2019  Volume 8, Issue 2

    Abstract: The type II secretion system (T2SS) delivers toxins and a range of hydrolytic enzymes, including proteases, lipases, and carbohydrate-active enzymes, to the cell surface or extracellular space of Gram-negative bacteria. Its contribution to survival of ... ...

    Abstract The type II secretion system (T2SS) delivers toxins and a range of hydrolytic enzymes, including proteases, lipases, and carbohydrate-active enzymes, to the cell surface or extracellular space of Gram-negative bacteria. Its contribution to survival of both extracellular and intracellular pathogens as well as environmental species of proteobacteria is evident. This dynamic, multicomponent machinery spans the entire cell envelope and consists of a cytoplasmic ATPase, several inner membrane proteins, a periplasmic pseudopilus, and a secretin pore embedded in the outer membrane. Despite the
    MeSH term(s) Adenosine Triphosphatases/metabolism ; Bacterial Proteins/metabolism ; Cryoelectron Microscopy ; Fimbriae, Bacterial/metabolism ; Fimbriae, Bacterial/ultrastructure ; Gram-Negative Bacteria/metabolism ; Membrane Proteins/metabolism ; Models, Molecular ; Periplasm/metabolism ; Protein Binding ; Secretin/metabolism ; Type II Secretion Systems/chemistry ; Type II Secretion Systems/metabolism
    Chemical Substances Bacterial Proteins ; Membrane Proteins ; Type II Secretion Systems ; Secretin (1393-25-5) ; Adenosine Triphosphatases (EC 3.6.1.-)
    Language English
    Publishing date 2019-03-15
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, U.S. Gov't, Non-P.H.S. ; Review
    ISSN 2324-6200
    ISSN (online) 2324-6200
    DOI 10.1128/ecosalplus.ESP-0034-2018
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: Functional Analysis of EspM, an ESX-1-Associated Transcription Factor in Mycobacterium marinum.

    Sanchez, Kevin G / Prest, Rebecca J / Nicholson, Kathleen R / Korotkov, Konstantin V / Champion, Patricia A

    Journal of bacteriology

    2022  Volume 204, Issue 12, Page(s) e0023322

    Abstract: Pathogenic mycobacteria use the ESX-1 secretion system to escape the macrophage phagosome and survive infection. We demonstrated that the ESX-1 system is regulated by feedback control in Mycobacterium marinum, a nontuberculous pathogen and model for the ... ...

    Abstract Pathogenic mycobacteria use the ESX-1 secretion system to escape the macrophage phagosome and survive infection. We demonstrated that the ESX-1 system is regulated by feedback control in Mycobacterium marinum, a nontuberculous pathogen and model for the human pathogen Mycobacterium tuberculosis. In the presence of a functional ESX-1 system, the WhiB6 transcription factor upregulates expression of ESX-1 substrate genes. In the absence of an assembled ESX-1 system, the conserved transcription factor, EspM, represses
    MeSH term(s) Bacterial Proteins/genetics ; Bacterial Proteins/metabolism ; Gene Expression Regulation, Bacterial ; Mycobacterium marinum/genetics ; Mycobacterium tuberculosis/genetics ; Transcription Factors/genetics ; Transcription Factors/metabolism ; Type VII Secretion Systems/metabolism ; Virulence Factors/genetics
    Chemical Substances Bacterial Proteins ; Transcription Factors ; Type VII Secretion Systems ; Virulence Factors
    Language English
    Publishing date 2022-11-30
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural
    ZDB-ID 2968-3
    ISSN 1098-5530 ; 0021-9193
    ISSN (online) 1098-5530
    ISSN 0021-9193
    DOI 10.1128/jb.00233-22
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  3. Article ; Online: Development and characterization of nanobodies that specifically target the oncogenic Phosphatase of Regenerating Liver-3 (PRL-3) and impact its interaction with a known binding partner, CNNM3.

    Smith, Caroline N / Kihn, Kyle / Williamson, Zachary A / Chow, K Martin / Hersh, Louis B / Korotkov, Konstantin V / Deredge, Daniel / Blackburn, Jessica S

    PloS one

    2023  Volume 18, Issue 5, Page(s) e0285964

    Abstract: Phosphatase of Regenerating Liver-3 (PRL-3) is associated with cancer progression and metastasis. The mechanisms that drive PRL-3's oncogenic functions are not well understood, partly due to a lack of research tools available to study this protein. We ... ...

    Abstract Phosphatase of Regenerating Liver-3 (PRL-3) is associated with cancer progression and metastasis. The mechanisms that drive PRL-3's oncogenic functions are not well understood, partly due to a lack of research tools available to study this protein. We have begun to address these issues by developing alpaca-derived single domain antibodies, or nanobodies, targeting PRL-3 with a KD of 30-300 nM and no activity towards highly homologous family members PRL-1 and PRL-2. We found that longer and charged N-terminal tags on PRL-3, such as GFP and FLAG, changed PRL-3 localization compared to untagged protein, indicating that the nanobodies may provide new insights into PRL-3 trafficking and function. The nanobodies perform equally, if not better, than commercially available antibodies in immunofluorescence and immunoprecipitation. Finally, hydrogen-deuterium exchange mass spectrometry (HDX-MS) showed that the nanobodies bind partially within the PRL-3 active site and can interfere with PRL-3 phosphatase activity. Co-immunoprecipitation with a known PRL-3 active site binding partner, the CBS domain of metal transporter CNNM3, showed that the nanobodies reduced the amount of PRL-3:CBS inter-action. The potential of blocking this interaction is highly relevant in cancer, as multiple research groups have shown that PRL-3 binding to CNNM proteins is sufficient to promote metastatic growth in mouse models. The anti-PRL-3 nanobodies represent an important expansion of the research tools available to study PRL-3 function and can be used to define the role of PRL-3 in cancer progression.
    MeSH term(s) Animals ; Mice ; Antibodies ; Camelids, New World ; Disease Models, Animal ; Single-Domain Antibodies ; Neoplasms
    Chemical Substances Antibodies ; Single-Domain Antibodies
    Language English
    Publishing date 2023-05-23
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural
    ZDB-ID 2267670-3
    ISSN 1932-6203 ; 1932-6203
    ISSN (online) 1932-6203
    ISSN 1932-6203
    DOI 10.1371/journal.pone.0285964
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  4. Article ; Online: Targeting phosphatases of regenerating liver (PRLs) in cancer.

    Wei, Min / Korotkov, Konstantin V / Blackburn, Jessica S

    Pharmacology & therapeutics

    2018  Volume 190, Page(s) 128–138

    Abstract: The phosphatase of regenerating liver (PRL) family, also known as protein tyrosine phosphatase 4A (PTP4A), are dual-specificity phosphatases with largely unknown cellular functions. However, accumulating evidence indicates that PRLs are oncogenic across ... ...

    Abstract The phosphatase of regenerating liver (PRL) family, also known as protein tyrosine phosphatase 4A (PTP4A), are dual-specificity phosphatases with largely unknown cellular functions. However, accumulating evidence indicates that PRLs are oncogenic across a broad variety of human cancers. PRLs are highly expressed in advanced tumors and metastases compared to early stage cancers or matched healthy tissue, and high expression of PRLs often correlates with poor patient prognosis. Consequentially, PRLs have been considered potential therapeutic targets in cancer. Persistent efforts have been made to define their role and mechanism in cancer progression and to create specific PRL inhibitors for basic research and drug development. However, targeting PRLs with small molecules remains challenging due to the highly conserved active site of protein tyrosine phosphatases and a high degree of sequence similarity between the PRL protein families. Here, we review the current PRL inhibitors, including the strategies used for their identification, their biological efficacy, potency, and selectivity, with a special focus on how PRL structure can inform future efforts to develop specific PRL inhibitors.
    MeSH term(s) Animals ; Antineoplastic Agents/pharmacology ; Disease Progression ; Drug Development/methods ; Humans ; Molecular Targeted Therapy ; Neoplasm Staging ; Neoplasms/drug therapy ; Neoplasms/enzymology ; Neoplasms/pathology ; Protein Tyrosine Phosphatases/antagonists & inhibitors ; Protein Tyrosine Phosphatases/metabolism
    Chemical Substances Antineoplastic Agents ; Protein Tyrosine Phosphatases (EC 3.1.3.48)
    Language English
    Publishing date 2018-06-05
    Publishing country England
    Document type Journal Article ; Review
    ZDB-ID 194735-7
    ISSN 1879-016X ; 0163-7258
    ISSN (online) 1879-016X
    ISSN 0163-7258
    DOI 10.1016/j.pharmthera.2018.05.014
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  5. Article ; Online: PE5-PPE4-EspG

    Williamson, Zachary A / Chaton, Catherine T / Ciocca, William A / Korotkova, Natalia / Korotkov, Konstantin V

    The Journal of biological chemistry

    2020  Volume 295, Issue 36, Page(s) 12706–12715

    Abstract: Mycobacterium ... ...

    Abstract Mycobacterium tuberculosis
    MeSH term(s) Amino Acid Motifs ; Bacterial Proteins/genetics ; Bacterial Proteins/metabolism ; Bacterial Secretion Systems/genetics ; Bacterial Secretion Systems/metabolism ; Mycobacterium tuberculosis/genetics ; Mycobacterium tuberculosis/metabolism ; Protein Domains
    Chemical Substances Bacterial Proteins ; Bacterial Secretion Systems
    Language English
    Publishing date 2020-07-16
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, U.S. Gov't, Non-P.H.S.
    ZDB-ID 2997-x
    ISSN 1083-351X ; 0021-9258
    ISSN (online) 1083-351X
    ISSN 0021-9258
    DOI 10.1074/jbc.RA120.012698
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article ; Online: Heterogeneity of the group B streptococcal type VII secretion system and influence on colonization of the female genital tract.

    Spencer, Brady L / Job, Alyx M / Robertson, Clare M / Hameed, Zainab A / Serchejian, Camille / Wiafe-Kwakye, Caitlin S / Mendonça, Jéssica C / Apolonio, Morgan A / Nagao, Prescilla E / Neely, Melody N / Korotkova, Natalia / Korotkov, Konstantin V / Patras, Kathryn A / Doran, Kelly S

    Molecular microbiology

    2023  Volume 120, Issue 2, Page(s) 258–275

    Abstract: Type VIIb secretion systems (T7SSb) in Gram-positive bacteria facilitate physiology, interbacterial competition, and/or virulence via EssC ATPase-driven secretion of small ɑ-helical proteins and toxins. Recently, we characterized T7SSb in group B ... ...

    Abstract Type VIIb secretion systems (T7SSb) in Gram-positive bacteria facilitate physiology, interbacterial competition, and/or virulence via EssC ATPase-driven secretion of small ɑ-helical proteins and toxins. Recently, we characterized T7SSb in group B Streptococcus (GBS), a leading cause of infection in newborns and immunocompromised adults. GBS T7SS comprises four subtypes based on variation in the C-terminus of EssC and the repertoire of downstream effectors; however, the intraspecies diversity of GBS T7SS and impact on GBS-host interactions remains unknown. Bioinformatic analysis indicates that GBS T7SS loci encode subtype-specific putative effectors, which have low interspecies and inter-subtype homology but contain similar domains/motifs and therefore may serve similar functions. We further identify orphaned GBS WXG100 proteins. Functionally, we show that GBS T7SS subtype I and III strains secrete EsxA in vitro and that in subtype I strain CJB111, esxA1 appears to be differentially transcribed from the T7SS operon. Furthermore, we observe subtype-specific effects of GBS T7SS on host colonization, as CJB111 subtype I but not CNCTC 10/84 subtype III T7SS promotes GBS vaginal colonization. Finally, we observe that T7SS subtypes I and II are the predominant subtypes in clinical GBS isolates. This study highlights the potential impact of T7SS heterogeneity on host-GBS interactions.
    MeSH term(s) Infant, Newborn ; Female ; Humans ; Bacterial Proteins/genetics ; Bacterial Proteins/metabolism ; Type VII Secretion Systems/genetics ; Virulence ; Operon/genetics ; Genitalia, Female/metabolism ; Streptococcal Infections/microbiology ; Streptococcus agalactiae/genetics ; Streptococcus agalactiae/metabolism ; Vagina/metabolism ; Vagina/microbiology
    Chemical Substances Bacterial Proteins ; Type VII Secretion Systems
    Language English
    Publishing date 2023-06-26
    Publishing country England
    Document type Journal Article ; Research Support, U.S. Gov't, Non-P.H.S. ; Research Support, Non-U.S. Gov't ; Research Support, N.I.H., Extramural
    ZDB-ID 619315-8
    ISSN 1365-2958 ; 0950-382X
    ISSN (online) 1365-2958
    ISSN 0950-382X
    DOI 10.1111/mmi.15115
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  7. Article: Heterogeneity of the group B streptococcal type VII secretion system and influence on colonization of the female genital tract.

    Spencer, Brady L / Job, Alyx M / Robertson, Clare M / Hameed, Zainab A / Serchejian, Camille / Wiafe-Kwakye, Caitlin S / Mendonça, Jéssica C / Apolonio, Morgan A / Nagao, Prescilla E / Neely, Melody N / Korotkova, Natalia / Korotkov, Konstantin V / Patras, Kathryn A / Doran, Kelly S

    bioRxiv : the preprint server for biology

    2023  

    Abstract: Type VIIb secretion systems (T7SSb) in Gram-positive bacteria facilitate physiology, interbacterial competition, and/or virulence via EssC ATPase-driven secretion of small ɑ-helical proteins and toxins. Recently, we characterized T7SSb in group ... ...

    Abstract Type VIIb secretion systems (T7SSb) in Gram-positive bacteria facilitate physiology, interbacterial competition, and/or virulence via EssC ATPase-driven secretion of small ɑ-helical proteins and toxins. Recently, we characterized T7SSb in group B
    Language English
    Publishing date 2023-01-25
    Publishing country United States
    Document type Preprint
    DOI 10.1101/2023.01.25.525443
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  8. Article ; Online: Functional and structural studies on the Neisseria gonorrhoeae GmhA, the first enzyme in the glycero-manno-heptose biosynthesis pathways, demonstrate a critical role in lipooligosaccharide synthesis and gonococcal viability.

    Wierzbicki, Igor H / Zielke, Ryszard A / Korotkov, Konstantin V / Sikora, Aleksandra E

    MicrobiologyOpen

    2017  Volume 6, Issue 2

    Abstract: Sedoheptulose-7-phosphate isomerase, GmhA, is the first enzyme in the biosynthesis of nucleotide-activated-glycero-manno-heptoses and an attractive, yet underexploited, target for development of broad-spectrum antibiotics. We demonstrated that GmhA ... ...

    Abstract Sedoheptulose-7-phosphate isomerase, GmhA, is the first enzyme in the biosynthesis of nucleotide-activated-glycero-manno-heptoses and an attractive, yet underexploited, target for development of broad-spectrum antibiotics. We demonstrated that GmhA homologs in Neisseria gonorrhoeae and N. meningitidis (hereafter called GmhA
    MeSH term(s) Bacterial Proteins/genetics ; Bacterial Proteins/ultrastructure ; Carbohydrate Epimerases/genetics ; Carbohydrate Epimerases/ultrastructure ; Catalytic Domain/genetics ; Heptoses/biosynthesis ; Lipopolysaccharides/biosynthesis ; Mutagenesis, Site-Directed ; Neisseria gonorrhoeae/enzymology ; Neisseria gonorrhoeae/genetics ; Neisseria meningitidis/enzymology ; Neisseria meningitidis/genetics ; Sugar Phosphates/metabolism
    Chemical Substances Bacterial Proteins ; Heptoses ; Lipopolysaccharides ; Sugar Phosphates ; lipid-linked oligosaccharides ; sedoheptulose 7-phosphate (2646-35-7) ; glycero-manno-heptose (4305-74-2) ; Carbohydrate Epimerases (EC 5.1.3.-) ; sedoheptulose-7-phosphate isomerase, Neisseria gonorrhoeae (EC 5.1.3.-)
    Language English
    Publishing date 2017-01-07
    Publishing country England
    Document type Journal Article
    ZDB-ID 2661368-2
    ISSN 2045-8827 ; 2045-8827
    ISSN (online) 2045-8827
    ISSN 2045-8827
    DOI 10.1002/mbo3.432
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  9. Article ; Online: Targeting an Essential GTPase Obg for the Development of Broad-Spectrum Antibiotics.

    Bonventre, Josephine A / Zielke, Ryszard A / Korotkov, Konstantin V / Sikora, Aleksandra E

    PloS one

    2016  Volume 11, Issue 2, Page(s) e0148222

    Abstract: A promising new drug target for the development of novel broad-spectrum antibiotics is the highly conserved small GTPase Obg (YhbZ, CgtA), a protein essential for the survival of all bacteria including Neisseria gonorrhoeae (GC). GC is the agent of ... ...

    Abstract A promising new drug target for the development of novel broad-spectrum antibiotics is the highly conserved small GTPase Obg (YhbZ, CgtA), a protein essential for the survival of all bacteria including Neisseria gonorrhoeae (GC). GC is the agent of gonorrhea, a prevalent sexually transmitted disease resulting in serious consequences on reproductive and neonatal health. A preventive anti-gonorrhea vaccine does not exist, and options for effective antibiotic treatments are increasingly limited. To address the dire need for alternative antimicrobial strategies, we have designed and optimized a 384-well GTPase assay to identify inhibitors of Obg using as a model Obg protein from GC, ObgGC. The assay was validated with a pilot screen of 40,000 compounds and achieved an average Z' value of 0.58 ± 0.02, which suggests a robust assay amenable to high-throughput screening. We developed secondary assessments for identified lead compounds that utilize the interaction between ObgGC and fluorescent guanine nucleotide analogs, mant-GTP and mant-GDP, and an ObgGC variant with multiple alterations in the G-domains that prevent nucleotide binding. To evaluate the broad-spectrum potential of ObgGC inhibitors, Obg proteins of Klebsiella pneumoniae and methicillin-resistant Staphylococcus aureus were assessed using the colorimetric and fluorescence-based activity assays. These approaches can be useful in identifying broad-spectrum Obg inhibitors and advancing the therapeutic battle against multidrug resistant bacteria.
    MeSH term(s) Anti-Bacterial Agents/pharmacology ; Bacterial Proteins/antagonists & inhibitors ; Chelating Agents/pharmacology ; Drug Evaluation, Preclinical ; Drug Resistance, Multiple/drug effects ; Enzyme Inhibitors/pharmacology ; GTP-Binding Proteins/antagonists & inhibitors ; Molecular Targeted Therapy ; Neisseria gonorrhoeae/drug effects ; Neisseria gonorrhoeae/enzymology ; Solvents/pharmacology
    Chemical Substances Anti-Bacterial Agents ; Bacterial Proteins ; Chelating Agents ; Enzyme Inhibitors ; Obg GTP-binding protein, Bacteria ; Solvents ; GTP-Binding Proteins (EC 3.6.1.-)
    Language English
    Publishing date 2016-02-05
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't
    ISSN 1932-6203
    ISSN (online) 1932-6203
    DOI 10.1371/journal.pone.0148222
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  10. Article ; Online: Crystal structure of the full-length ATPase GspE from the Vibrio vulnificus type II secretion system in complex with the cytoplasmic domain of GspL.

    Lu, Connie / Korotkov, Konstantin V / Hol, Wim G J

    Journal of structural biology

    2014  Volume 187, Issue 3, Page(s) 223–235

    Abstract: The type II secretion system (T2SS) is present in many Gram-negative bacteria and is responsible for secreting a large number of folded proteins, including major virulence factors, across the outer membrane. The T2SS consists of 11-15 different proteins ... ...

    Abstract The type II secretion system (T2SS) is present in many Gram-negative bacteria and is responsible for secreting a large number of folded proteins, including major virulence factors, across the outer membrane. The T2SS consists of 11-15 different proteins most of which are present in multiple copies in the assembled secretion machinery. The ATPase GspE, essential for the functioning of the T2SS, contains three domains (N1E, N2E and CTE) of which the N1E domain is associated with the cytoplasmic domain of the inner membrane protein GspL. Here we describe and analyze the structure of the GspE•cyto-GspL complex from Vibrio vulnificus in the presence of an ATP analog, AMPPNP. There are three such ∼83 kDa complexes per asymmetric unit with essentially the same structure. The N2E and CTE domains of a single V. vulnificus GspE subunit adopt a mutual orientation that has not been seen before in any of the previous GspE structures, neither in structures of related ATPases from other secretion systems. This underlines the tremendous conformational flexibility of the T2SS secretion ATPase. Cyto-GspL interacts not only with the N1E domain, but also with the CTE domain and is even in contact with AMPPNP. Moreover, the cyto-GspL domains engage in two types of mutual interactions, resulting in two essentially identical, but crystallographically independent, "cyto-GspL rods" that run throughout the crystal. Very similar rods are present in previous crystals of cyto-GspL and of the N1E•cyto-GspL complex. This arrangement, now seen four times in three entirely different crystal forms, involves contacts between highly conserved residues suggesting a role in the biogenesis or the secretion mechanism or both of the T2SS.
    MeSH term(s) Adenosine Triphosphatases/chemistry ; Adenosine Triphosphatases/genetics ; Adenosine Triphosphatases/metabolism ; Amino Acid Sequence ; Bacterial Proteins/chemistry ; Bacterial Proteins/genetics ; Bacterial Proteins/metabolism ; Binding Sites/genetics ; Crystallography, X-Ray ; Membrane Proteins/chemistry ; Membrane Proteins/genetics ; Membrane Proteins/metabolism ; Models, Molecular ; Molecular Sequence Data ; Multiprotein Complexes/chemistry ; Multiprotein Complexes/metabolism ; Protein Structure, Tertiary ; Protein Subunits/chemistry ; Protein Subunits/genetics ; Protein Subunits/metabolism ; Sequence Homology, Amino Acid ; Vibrio vulnificus/genetics ; Vibrio vulnificus/metabolism
    Chemical Substances Bacterial Proteins ; Membrane Proteins ; Multiprotein Complexes ; Protein Subunits ; Adenosine Triphosphatases (EC 3.6.1.-)
    Language English
    Publishing date 2014-08-01
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, U.S. Gov't, Non-P.H.S.
    ZDB-ID 1032718-6
    ISSN 1095-8657 ; 1047-8477
    ISSN (online) 1095-8657
    ISSN 1047-8477
    DOI 10.1016/j.jsb.2014.07.006
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