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  1. Article ; Online: Structure of the M. tuberculosis DnaK-GrpE complex reveals how key DnaK roles are controlled.

    Xiao, Xiansha / Fay, Allison / Molina, Pablo Santos / Kovach, Amanda / Glickman, Michael S / Li, Huilin

    Nature communications

    2024  Volume 15, Issue 1, Page(s) 660

    Abstract: The molecular chaperone DnaK is essential for viability of Mycobacterium tuberculosis (Mtb). DnaK hydrolyzes ATP to fold substrates, and the resulting ADP is exchanged for ATP by the nucleotide exchange factor GrpE. It has been unclear how GrpE couples ... ...

    Abstract The molecular chaperone DnaK is essential for viability of Mycobacterium tuberculosis (Mtb). DnaK hydrolyzes ATP to fold substrates, and the resulting ADP is exchanged for ATP by the nucleotide exchange factor GrpE. It has been unclear how GrpE couples DnaK's nucleotide exchange with substrate release. Here we report a cryo-EM analysis of GrpE bound to an intact Mtb DnaK, revealing an asymmetric 1:2 DnaK-GrpE complex. The GrpE dimer ratchets to modulate both DnaK nucleotide-binding domain and the substrate-binding domain. We further show that the disordered GrpE N-terminus is critical for substrate release, and that the DnaK-GrpE interface is essential for protein folding activity both in vitro and in vivo. Therefore, the Mtb GrpE dimer allosterically regulates DnaK to concomitantly release ADP in the nucleotide-binding domain and substrate peptide in the substrate-binding domain.
    MeSH term(s) Humans ; Mycobacterium tuberculosis ; Nucleotides ; Polymers ; Tuberculosis ; Adenosine Triphosphate
    Chemical Substances Nucleotides ; Polymers ; Adenosine Triphosphate (8L70Q75FXE)
    Language English
    Publishing date 2024-01-22
    Publishing country England
    Document type Journal Article
    ZDB-ID 2553671-0
    ISSN 2041-1723 ; 2041-1723
    ISSN (online) 2041-1723
    ISSN 2041-1723
    DOI 10.1038/s41467-024-44933-9
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: Mycobacterial helicase Lhr abets resistance to DNA crosslinking agents mitomycin C and cisplatin.

    Warren, Garrett M / Ejaz, Anam / Fay, Allison / Glickman, Michael S / Shuman, Stewart

    Nucleic acids research

    2023  Volume 51, Issue 1, Page(s) 218–235

    Abstract: Mycobacterium smegmatis Lhr exemplifies a novel clade of helicases composed of an N-terminal ATPase/helicase domain (Lhr-Core) and a large C-terminal domain (Lhr-CTD) that nucleates a unique homo-tetrameric quaternary structure. Expression of Lhr, and ... ...

    Abstract Mycobacterium smegmatis Lhr exemplifies a novel clade of helicases composed of an N-terminal ATPase/helicase domain (Lhr-Core) and a large C-terminal domain (Lhr-CTD) that nucleates a unique homo-tetrameric quaternary structure. Expression of Lhr, and its operonic neighbor Nei2, is induced in mycobacteria exposed to mitomycin C (MMC). Here we report that lhr deletion sensitizes M. smegmatis to killing by DNA crosslinkers MMC and cisplatin but not to killing by monoadduct-forming alkylating agent methyl methanesulfonate or UV irradiation. Testing complementation of MMC and cisplatin sensitivity by expression of Lhr mutants in Δlhr cells established that: (i) Lhr-CTD is essential for DNA repair activity, such that Lhr-Core does not suffice; (ii) ATPase-defective mutant D170A/E171A fails to complement; (iii) ATPase-active, helicase-defective mutant W597A fails to complement and (iv) alanine mutations at the CTD-CTD interface that interdict homo-tetramer formation result in failure to complement. Our results instate Lhr's ATP-driven motor as an agent of inter-strand crosslink repair in vivo, contingent on Lhr's tetrameric quaternary structure. We characterize M. smegmatis Nei2 as a monomeric enzyme with AP β-lyase activity on single-stranded DNA. Counter to previous reports, we find Nei2 is inactive as a lyase at a THF abasic site and has feeble uracil glycosylase activity.
    MeSH term(s) Mitomycin/pharmacology ; Cisplatin/pharmacology ; Bacterial Proteins/metabolism ; DNA Helicases/metabolism ; Mycobacterium/genetics ; Adenosine Triphosphatases/metabolism ; DNA Repair/genetics ; DNA, Single-Stranded
    Chemical Substances Mitomycin (50SG953SK6) ; Cisplatin (Q20Q21Q62J) ; Bacterial Proteins ; DNA Helicases (EC 3.6.4.-) ; Adenosine Triphosphatases (EC 3.6.1.-) ; DNA, Single-Stranded
    Language English
    Publishing date 2023-01-04
    Publishing country England
    Document type Journal Article ; Research Support, N.I.H., Extramural
    ZDB-ID 186809-3
    ISSN 1362-4962 ; 1362-4954 ; 0301-5610 ; 0305-1048
    ISSN (online) 1362-4962 ; 1362-4954
    ISSN 0301-5610 ; 0305-1048
    DOI 10.1093/nar/gkac1222
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article: Running the Numbers: Drug Expenditure Trends in North Carolina Medicaid.

    Fay, Allison E / Pfeiffenberger, Trista

    North Carolina medical journal

    2017  Volume 78, Issue 3, Page(s) 208–211

    MeSH term(s) Health Expenditures/statistics & numerical data ; Humans ; Medicaid/economics ; Medicaid/statistics & numerical data ; North Carolina ; Pharmaceutical Preparations/economics ; Pharmaceutical Services/economics ; Pharmaceutical Services/statistics & numerical data ; United States
    Chemical Substances Pharmaceutical Preparations
    Language English
    Publishing date 2017-05
    Publishing country United States
    Document type Journal Article
    ZDB-ID 422795-5
    ISSN 0029-2559
    ISSN 0029-2559
    DOI 10.18043/ncm.78.3.208
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article ; Online: Roles for mycobacterial DinB2 in frameshift and substitution mutagenesis.

    Dupuy, Pierre / Ghosh, Shreya / Fay, Allison / Adefisayo, Oyindamola / Gupta, Richa / Shuman, Stewart / Glickman, Michael S

    eLife

    2023  Volume 12

    Abstract: Translesion synthesis by translesion polymerases is a conserved mechanism of DNA damage tolerance. In bacteria, DinB enzymes are the widely distributed promutagenic translesion polymerases. The role of DinBs in mycobacterial mutagenesis was unclear until ...

    Abstract Translesion synthesis by translesion polymerases is a conserved mechanism of DNA damage tolerance. In bacteria, DinB enzymes are the widely distributed promutagenic translesion polymerases. The role of DinBs in mycobacterial mutagenesis was unclear until recent studies revealed a role for mycobacterial DinB1 in substitution and frameshift mutagenesis, overlapping with that of translesion polymerase DnaE2.
    MeSH term(s) Frameshift Mutation ; Bacterial Proteins/genetics ; Bacterial Proteins/chemistry ; Mutagenesis ; DNA Repair ; Mycobacterium tuberculosis/genetics
    Chemical Substances Bacterial Proteins
    Language English
    Publishing date 2023-05-04
    Publishing country England
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't
    ZDB-ID 2687154-3
    ISSN 2050-084X ; 2050-084X
    ISSN (online) 2050-084X
    ISSN 2050-084X
    DOI 10.7554/eLife.83094
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article ; Online: The DnaK Chaperone System Buffers the Fitness Cost of Antibiotic Resistance Mutations in Mycobacteria.

    Fay, Allison / Philip, John / Saha, Priya / Hendrickson, Ronald C / Glickman, Michael S / Burns-Huang, Kristin

    mBio

    2021  Volume 12, Issue 2

    Abstract: Chaperones aid in protein folding and maintenance of protein integrity. In doing so, they have the unique ability to directly stabilize resistance-conferring amino acid substitutions in drug targets and to counter the stress imparted by these ... ...

    Abstract Chaperones aid in protein folding and maintenance of protein integrity. In doing so, they have the unique ability to directly stabilize resistance-conferring amino acid substitutions in drug targets and to counter the stress imparted by these substitutions, thus supporting heritable antimicrobial resistance (AMR). We asked whether chaperones support AMR in
    MeSH term(s) Anti-Bacterial Agents/pharmacology ; Bacterial Proteins/genetics ; Bacterial Proteins/metabolism ; DNA-Directed RNA Polymerases/genetics ; DNA-Directed RNA Polymerases/metabolism ; Drug Resistance, Bacterial ; Humans ; Molecular Chaperones/genetics ; Molecular Chaperones/metabolism ; Mutation ; Mycobacterium smegmatis/drug effects ; Mycobacterium smegmatis/genetics ; Mycobacterium smegmatis/metabolism ; Mycobacterium tuberculosis/drug effects ; Mycobacterium tuberculosis/genetics ; Mycobacterium tuberculosis/metabolism ; Protein Binding ; Tuberculosis/microbiology
    Chemical Substances Anti-Bacterial Agents ; Bacterial Proteins ; DnaK protein, Mycobacterium smegmatis ; Molecular Chaperones ; DNA-Directed RNA Polymerases (EC 2.7.7.6)
    Language English
    Publishing date 2021-03-30
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't
    ZDB-ID 2557172-2
    ISSN 2150-7511 ; 2161-2129
    ISSN (online) 2150-7511
    ISSN 2161-2129
    DOI 10.1128/mBio.00123-21
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article ; Online: An essential nonredundant role for mycobacterial DnaK in native protein folding.

    Fay, Allison / Glickman, Michael S

    PLoS genetics

    2014  Volume 10, Issue 7, Page(s) e1004516

    Abstract: Protein chaperones are essential in all domains of life to prevent and resolve protein misfolding during translation and proteotoxic stress. HSP70 family chaperones, including E. coli DnaK, function in stress induced protein refolding and degradation, ... ...

    Abstract Protein chaperones are essential in all domains of life to prevent and resolve protein misfolding during translation and proteotoxic stress. HSP70 family chaperones, including E. coli DnaK, function in stress induced protein refolding and degradation, but are dispensable for cellular viability due to redundant chaperone systems that prevent global nascent peptide insolubility. However, the function of HSP70 chaperones in mycobacteria, a genus that includes multiple human pathogens, has not been examined. We find that mycobacterial DnaK is essential for cell growth and required for native protein folding in Mycobacterium smegmatis. Loss of DnaK is accompanied by proteotoxic collapse characterized by the accumulation of insoluble newly synthesized proteins. DnaK is required for solubility of large multimodular lipid synthases, including the essential lipid synthase FASI, and DnaK loss is accompanied by disruption of membrane structure and increased cell permeability. Trigger Factor is nonessential and has a minor role in native protein folding that is only evident in the absence of DnaK. In unstressed cells, DnaK localizes to multiple, dynamic foci, but relocalizes to focal protein aggregates during stationary phase or upon expression of aggregating peptides. Mycobacterial cells restart cell growth after proteotoxic stress by isolating persistent DnaK containing protein aggregates away from daughter cells. These results reveal unanticipated essential nonredunant roles for mycobacterial DnaK in mycobacteria and indicate that DnaK defines a unique susceptibility point in the mycobacterial proteostasis network.
    MeSH term(s) Bacterial Proteins/genetics ; Cell Survival/genetics ; Escherichia coli ; Escherichia coli Proteins/genetics ; HSP70 Heat-Shock Proteins/genetics ; Humans ; Molecular Chaperones/genetics ; Mycobacterium smegmatis/genetics ; Mycobacterium smegmatis/metabolism ; Protein Aggregation, Pathological/genetics ; Protein Folding ; Stress, Physiological/genetics
    Chemical Substances Bacterial Proteins ; DnaK protein, Mycobacterium smegmatis ; Escherichia coli Proteins ; HSP70 Heat-Shock Proteins ; Molecular Chaperones ; dnaK protein, E coli (EC 3.6.1.-)
    Language English
    Publishing date 2014-07-24
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural
    ZDB-ID 2186725-2
    ISSN 1553-7404 ; 1553-7390
    ISSN (online) 1553-7404
    ISSN 1553-7390
    DOI 10.1371/journal.pgen.1004516
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article ; Online: Structural basis for aggregate dissolution and refolding by the Mycobacterium tuberculosis ClpB-DnaK bi-chaperone system.

    Yin, Yanting / Feng, Xiang / Yu, Hongjun / Fay, Allison / Kovach, Amanda / Glickman, Michael S / Li, Huilin

    Cell reports

    2021  Volume 35, Issue 8, Page(s) 109166

    Abstract: The M. tuberculosis (Mtb) ClpB is a protein disaggregase that helps to rejuvenate the bacterial cell. DnaK is a protein foldase that can function alone, but it can also bind to the ClpB hexamer to physically couple protein disaggregation with protein ... ...

    Abstract The M. tuberculosis (Mtb) ClpB is a protein disaggregase that helps to rejuvenate the bacterial cell. DnaK is a protein foldase that can function alone, but it can also bind to the ClpB hexamer to physically couple protein disaggregation with protein refolding, although the molecular mechanism is not well understood. Here, we report the cryo-EM analysis of the Mtb ClpB-DnaK bi-chaperone in the presence of ATPγS and a protein substrate. We observe three ClpB conformations in the presence of DnaK, identify a conserved TGIP loop linking the oligonucleotide/oligosaccharide-binding domain and the nucleotide-binding domain that is important for ClpB function, derive the interface between the regulatory middle domain of the ClpB and the DnaK nucleotide-binding domain, and find that DnaK binding stabilizes, but does not bend or tilt, the ClpB middle domain. We propose a model for the synergistic actions of aggregate dissolution and refolding by the Mtb ClpB-DnaK bi-chaperone system.
    MeSH term(s) Bacterial Proteins/metabolism ; Endopeptidase Clp/metabolism ; Escherichia coli Proteins/metabolism ; Models, Molecular ; Mycobacterium tuberculosis/genetics ; Protein Refolding
    Chemical Substances Bacterial Proteins ; Escherichia coli Proteins ; Endopeptidase Clp (EC 3.4.21.92)
    Language English
    Publishing date 2021-06-17
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural
    ZDB-ID 2649101-1
    ISSN 2211-1247 ; 2211-1247
    ISSN (online) 2211-1247
    ISSN 2211-1247
    DOI 10.1016/j.celrep.2021.109166
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article ; Online: Evaluation of a pharmacist-led naloxone coprescribing program in primary care.

    Cariveau, Desmond / Fay, Allison E / Baker, David / Fagan, E Blake / Wilson, Courtenay Gilmore

    Journal of the American Pharmacists Association : JAPhA

    2019  Volume 59, Issue 6, Page(s) 867–871

    Abstract: Objectives: To determine the impact of a pharmacist-led coprescribing initiative on patient access to naloxone in a primary care setting.: Setting: Family medicine residency practice with embedded pharmacists in western North Carolina.: Practice ... ...

    Abstract Objectives: To determine the impact of a pharmacist-led coprescribing initiative on patient access to naloxone in a primary care setting.
    Setting: Family medicine residency practice with embedded pharmacists in western North Carolina.
    Practice innovation: In June 2016, clinical pharmacists embedded in a primary care clinic initiated a naloxone coprescribing initiative with the aim of increasing access to naloxone for patients on chronic opioid therapy who were on 50 mg or greater morphine-equivalents daily (MED), on a concomitant benzodiazepine, had a history of an overdose, or had a diagnosis of a substance use disorder. Pharmacists' roles included educating providers and clinical staff regarding naloxone, creating quick links within the electronic health record to more easily prescribe naloxone, identifying patients who met criteria for naloxone, and counseling patients about naloxone.
    Evaluation: This study was a single-cohort pre- and postintervention study. One year after initiation of the program, data were manually collected to assess the rates of naloxone prescribing and the reason for requiring naloxone. In addition, pharmacy students called pharmacies to determine fill rates and obtain reasons given by patients for not filling naloxone.
    Results: A total of 234 patients remained candidates for naloxone at the end of 1 year. Naloxone coprescribing increased from 3.4% at baseline to 37.2% at follow-up (P = 0.0001). Seventy-one percent of patients required naloxone because of chronic opioid therapy doses of 50 mg or more MED, 55% were on a benzodiazepine, 6% had a diagnosis of a substance use disorder, and 1% had a history of overdose. Of the patients who received a naloxone prescription, 31.4% filled it.
    Conclusion: Embedded clinical pharmacists in primary care have the potential to increase naloxone coprescribing for high-risk patients treated with chronic opioid therapy for pain.
    MeSH term(s) Adult ; Aged ; Aged, 80 and over ; Analgesics, Opioid/administration & dosage ; Analgesics, Opioid/adverse effects ; Chronic Pain/drug therapy ; Drug Overdose/prevention & control ; Female ; Health Services Accessibility ; Humans ; Male ; Middle Aged ; Naloxone/administration & dosage ; Narcotic Antagonists/administration & dosage ; Pharmaceutical Services/organization & administration ; Pharmacists/organization & administration ; Practice Patterns, Physicians'/organization & administration ; Primary Health Care/organization & administration ; Professional Role ; Students, Pharmacy
    Chemical Substances Analgesics, Opioid ; Narcotic Antagonists ; Naloxone (36B82AMQ7N)
    Language English
    Publishing date 2019-08-26
    Publishing country United States
    Document type Journal Article ; Research Support, U.S. Gov't, P.H.S.
    ZDB-ID 2118585-2
    ISSN 1544-3450 ; 1544-3191 ; 1086-5802
    ISSN (online) 1544-3450
    ISSN 1544-3191 ; 1086-5802
    DOI 10.1016/j.japh.2019.07.012
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  9. Article ; Online: Care team perspectives on community pharmacy enhanced services.

    Fay, Allison E / Ferreri, Stefanie P / Shepherd, Greene / Lundeen, Kristin / Tong, Gretchen L / Pfeiffenberger, Trista

    Journal of the American Pharmacists Association : JAPhA

    2018  Volume 58, Issue 4S, Page(s) S83–S88.e3

    Abstract: Objectives: To determine the awareness, collaboration, and perceived values and barriers of enhanced pharmacy services from care managers and primary care practice responders.: Methods: An electronic questionnaire was sent to 1648 primary care ... ...

    Abstract Objectives: To determine the awareness, collaboration, and perceived values and barriers of enhanced pharmacy services from care managers and primary care practice responders.
    Methods: An electronic questionnaire was sent to 1648 primary care practices and 600 care managers that work in 76 North Carolina counties containing an enhanced-service community pharmacy. Questionnaires were distributed in January 2017 and responses collected for 7 weeks. The questionnaire collected data on the awareness and perceived value of enhanced pharmacy services, preferred method and level of communication for referral, and barriers to using enhanced services. Data were gathered with the use of Likert-type, rank-order, dichotomous, and multiple-choice questions. Data were analyzed with the use of descriptive statistics, and group mean responses were compared by means of t tests.
    Results: Data analysis was performed in March 2017. Response rates were 5.4% (n = 89) from practice responders and 45% (n = 270) from care managers. In the responses received, 35% of practice responders and 88% of care managers were familiar with enhanced services offered by community pharmacies. A majority of respondents thought that enhanced pharmacy services are valuable, with more than 85% of practice responders agreeing that partnering with an enhanced-service pharmacy can help to improve patient health outcomes. Lack of knowledge of enhanced-service pharmacies, services offered, and the referral process were identified as significant barriers for practice responders.
    Conclusion: Community-based pharmacies have an opportunity to collaborate with patient-centered medical home teams to provide enhanced pharmacy services, but provider outreach and education on enhanced services offered and the referral process are necessary to maximize this collaboration.
    MeSH term(s) Community Pharmacy Services/statistics & numerical data ; Humans ; Pharmacies/statistics & numerical data ; Pharmacists/statistics & numerical data ; Primary Health Care/statistics & numerical data ; Professional Role ; Surveys and Questionnaires
    Language English
    Publishing date 2018-07-11
    Publishing country United States
    Document type Journal Article
    ZDB-ID 2118585-2
    ISSN 1544-3450 ; 1544-3191 ; 1086-5802
    ISSN (online) 1544-3450
    ISSN 1544-3191 ; 1086-5802
    DOI 10.1016/j.japh.2018.05.009
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article ; Online: Bacillus subtilis homologs of MviN (MurJ), the putative Escherichia coli lipid II flippase, are not essential for growth.

    Fay, Allison / Dworkin, Jonathan

    Journal of bacteriology

    2009  Volume 191, Issue 19, Page(s) 6020–6028

    Abstract: Although peptidoglycan synthesis is one of the best-studied metabolic pathways in bacteria, the mechanism underlying the membrane translocation of lipid II, the undecaprenyl-disaccharide pentapeptide peptidoglycan precursor, remains mysterious. Recently, ...

    Abstract Although peptidoglycan synthesis is one of the best-studied metabolic pathways in bacteria, the mechanism underlying the membrane translocation of lipid II, the undecaprenyl-disaccharide pentapeptide peptidoglycan precursor, remains mysterious. Recently, it was proposed that the essential Escherichia coli mviN gene encodes the lipid II flippase. Bacillus subtilis contains four proteins that are putatively homologous to MviN, including SpoVB, previously reported to be necessary for spore cortex peptidoglycan synthesis during sporulation. MviN complemented the sporulation defect of a DeltaspoVB mutation, and SpoVB and another of the B. subtilis homologs, YtgP, complemented the growth defect of an E. coli strain depleted for MviN. Thus, these B. subtilis proteins are likely to be MviN homologs. However, B. subtilis strains lacking these four proteins have no defects in growth, indicating that they likely do not serve as lipid II flippases in this organism.
    MeSH term(s) Amino Acid Sequence ; Bacillus subtilis/genetics ; Bacillus subtilis/growth & development ; Bacillus subtilis/metabolism ; Bacterial Proteins/chemistry ; Bacterial Proteins/genetics ; Bacterial Proteins/physiology ; Computational Biology ; Escherichia coli Proteins/chemistry ; Escherichia coli Proteins/genetics ; Escherichia coli Proteins/physiology ; Genetic Complementation Test ; Membrane Proteins/chemistry ; Membrane Proteins/genetics ; Membrane Proteins/physiology ; Microscopy, Fluorescence ; Molecular Sequence Data ; Peptidoglycan/genetics ; Peptidoglycan/metabolism ; Sequence Homology, Amino Acid ; Uridine Diphosphate N-Acetylmuramic Acid/analogs & derivatives ; Uridine Diphosphate N-Acetylmuramic Acid/genetics ; Uridine Diphosphate N-Acetylmuramic Acid/metabolism
    Chemical Substances Bacterial Proteins ; Escherichia coli Proteins ; Membrane Proteins ; Peptidoglycan ; SpoVB protein, Bacillus ; Uridine Diphosphate N-Acetylmuramic Acid ; muramyl-NAc-(pentapeptide)pyrophosphoryl-undecaprenol
    Language English
    Publishing date 2009-08-07
    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.00605-09
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