In vivo processing and antibiotic activity of microcin B17 analogs with varying ring content and altered bisheterocyclic sites

Ranabir Sinha Roy; Neil L. Kelleher; Jill C. Milne; Christopher T. Walsh

doi:10.1016/S1074-5521(99)80076-3

In vivo processing and antibiotic activity of microcin B17 analogs with varying ring content and altered bisheterocyclic sites

Ranabir Sinha Roy, Neil L. Kelleher, Jill C. Milne, Christopher T. Walsh^*

^*Corresponding author for this work

Molecular Biosciences

Research output: Contribution to journal › Article › peer-review

56 Scopus citations

Abstract

Background: The Escherichia coli peptide antibiotic microcin B17 (MccB17) contains four oxazole and four thiazole rings, and inhibits DNA gyrase. The role of individual and tandem pairs of heterocycles in bioactivity has not been determined previously. Results: The two tandem 4,2-bisheterocycles in MccB17 were varied by expression of MccB17 or mutants containing altered sequences at Gly39-Ser40-Cys41 or Gly54-Cys55-Ser56. A mixture of five-nine-ring MccB17 isoforms were separated and quantitated for antibiotic potency. Mutagenesis of the thiazole-oxazole pair significantly affected antibiotic activity compared with the upstream oxazole-thiazole, which might stabilize partially cyclized intermediates against proteolysis. Conclusions: Enzymatic heterocyclization in native MccB17 occurs distributively. Antibiotic activity correlates with the number of rings and is differentially sensitive to both the location and the identity of the 4,2-tandem heterocycle pairs in MccB17. Such tandem heterocycles might be useful pharmacophores in combinatorial libraries.

Original language	English (US)
Pages (from-to)	305-318
Number of pages	14
Journal	Chemistry and Biology
Volume	6
Issue number	5
DOIs	https://doi.org/10.1016/S1074-5521(99)80076-3
State	Published - May 1999

Funding

This research was supported by NIH Grant GM 20011 to C.T.W. R.S.R. is a Parke-Davis Fellow of the Life Sciences Research Foundation. N.L.K. is an NIH postdoctoral fellow (F32 Al 10087-02). J.C.M. is an American Cancer Society Postdoctoral Research Fellow (PF4332). We thank Frank Laukien, Gary Kruppa and Paul Speir of Bruker Daltonics for access to their FTMS instrument and for assistance with data collection. We also thank Alan Marshall for granting access the 9.4 Tesla ESI-FTMS mass spectrometer (National High-Field FT-ICR MS Facility, NHMFL, NSF CHE-94.13008), Roberto Kolter for helpful discussions and critical reading of the manuscript.

Keywords

Antibiotic
Gyrase
Heterocycles
Microcin B17
Mutagenesis

ASJC Scopus subject areas

Drug Discovery
Molecular Medicine
Molecular Biology
Biochemistry
Clinical Biochemistry
Pharmacology

Access to Document

10.1016/S1074-5521(99)80076-3

Cite this

@article{48708fc5f8104671b8884a71b00fc8b6,

title = "In vivo processing and antibiotic activity of microcin B17 analogs with varying ring content and altered bisheterocyclic sites",

abstract = "Background: The Escherichia coli peptide antibiotic microcin B17 (MccB17) contains four oxazole and four thiazole rings, and inhibits DNA gyrase. The role of individual and tandem pairs of heterocycles in bioactivity has not been determined previously. Results: The two tandem 4,2-bisheterocycles in MccB17 were varied by expression of MccB17 or mutants containing altered sequences at Gly39-Ser40-Cys41 or Gly54-Cys55-Ser56. A mixture of five-nine-ring MccB17 isoforms were separated and quantitated for antibiotic potency. Mutagenesis of the thiazole-oxazole pair significantly affected antibiotic activity compared with the upstream oxazole-thiazole, which might stabilize partially cyclized intermediates against proteolysis. Conclusions: Enzymatic heterocyclization in native MccB17 occurs distributively. Antibiotic activity correlates with the number of rings and is differentially sensitive to both the location and the identity of the 4,2-tandem heterocycle pairs in MccB17. Such tandem heterocycles might be useful pharmacophores in combinatorial libraries.",

keywords = "Antibiotic, Gyrase, Heterocycles, Microcin B17, Mutagenesis",

author = "Roy, {Ranabir Sinha} and Kelleher, {Neil L.} and Milne, {Jill C.} and Walsh, {Christopher T.}",

note = "Funding Information: This research was supported by NIH Grant GM 20011 to C.T.W. R.S.R. is a Parke-Davis Fellow of the Life Sciences Research Foundation. N.L.K. is an NIH postdoctoral fellow (F32 Al 10087-02). J.C.M. is an American Cancer Society Postdoctoral Research Fellow (PF4332). We thank Frank Laukien, Gary Kruppa and Paul Speir of Bruker Daltonics for access to their FTMS instrument and for assistance with data collection. We also thank Alan Marshall for granting access the 9.4 Tesla ESI-FTMS mass spectrometer (National High-Field FT-ICR MS Facility, NHMFL, NSF CHE-94.13008), Roberto Kolter for helpful discussions and critical reading of the manuscript.",

year = "1999",

month = may,

doi = "10.1016/S1074-5521(99)80076-3",

language = "English (US)",

volume = "6",

pages = "305--318",

journal = "Chemistry and Biology",

issn = "1074-5521",

publisher = "Elsevier Inc.",

number = "5",

}

TY - JOUR

T1 - In vivo processing and antibiotic activity of microcin B17 analogs with varying ring content and altered bisheterocyclic sites

AU - Roy, Ranabir Sinha

AU - Kelleher, Neil L.

AU - Milne, Jill C.

AU - Walsh, Christopher T.

N1 - Funding Information: This research was supported by NIH Grant GM 20011 to C.T.W. R.S.R. is a Parke-Davis Fellow of the Life Sciences Research Foundation. N.L.K. is an NIH postdoctoral fellow (F32 Al 10087-02). J.C.M. is an American Cancer Society Postdoctoral Research Fellow (PF4332). We thank Frank Laukien, Gary Kruppa and Paul Speir of Bruker Daltonics for access to their FTMS instrument and for assistance with data collection. We also thank Alan Marshall for granting access the 9.4 Tesla ESI-FTMS mass spectrometer (National High-Field FT-ICR MS Facility, NHMFL, NSF CHE-94.13008), Roberto Kolter for helpful discussions and critical reading of the manuscript.

PY - 1999/5

Y1 - 1999/5

N2 - Background: The Escherichia coli peptide antibiotic microcin B17 (MccB17) contains four oxazole and four thiazole rings, and inhibits DNA gyrase. The role of individual and tandem pairs of heterocycles in bioactivity has not been determined previously. Results: The two tandem 4,2-bisheterocycles in MccB17 were varied by expression of MccB17 or mutants containing altered sequences at Gly39-Ser40-Cys41 or Gly54-Cys55-Ser56. A mixture of five-nine-ring MccB17 isoforms were separated and quantitated for antibiotic potency. Mutagenesis of the thiazole-oxazole pair significantly affected antibiotic activity compared with the upstream oxazole-thiazole, which might stabilize partially cyclized intermediates against proteolysis. Conclusions: Enzymatic heterocyclization in native MccB17 occurs distributively. Antibiotic activity correlates with the number of rings and is differentially sensitive to both the location and the identity of the 4,2-tandem heterocycle pairs in MccB17. Such tandem heterocycles might be useful pharmacophores in combinatorial libraries.

AB - Background: The Escherichia coli peptide antibiotic microcin B17 (MccB17) contains four oxazole and four thiazole rings, and inhibits DNA gyrase. The role of individual and tandem pairs of heterocycles in bioactivity has not been determined previously. Results: The two tandem 4,2-bisheterocycles in MccB17 were varied by expression of MccB17 or mutants containing altered sequences at Gly39-Ser40-Cys41 or Gly54-Cys55-Ser56. A mixture of five-nine-ring MccB17 isoforms were separated and quantitated for antibiotic potency. Mutagenesis of the thiazole-oxazole pair significantly affected antibiotic activity compared with the upstream oxazole-thiazole, which might stabilize partially cyclized intermediates against proteolysis. Conclusions: Enzymatic heterocyclization in native MccB17 occurs distributively. Antibiotic activity correlates with the number of rings and is differentially sensitive to both the location and the identity of the 4,2-tandem heterocycle pairs in MccB17. Such tandem heterocycles might be useful pharmacophores in combinatorial libraries.

KW - Antibiotic

KW - Gyrase

KW - Heterocycles

KW - Microcin B17

KW - Mutagenesis

UR - http://www.scopus.com/inward/record.url?scp=0033133846&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0033133846&partnerID=8YFLogxK

U2 - 10.1016/S1074-5521(99)80076-3

DO - 10.1016/S1074-5521(99)80076-3

M3 - Article

C2 - 10322125

AN - SCOPUS:0033133846

SN - 1074-5521

VL - 6

SP - 305

EP - 318

JO - Chemistry and Biology

JF - Chemistry and Biology

IS - 5

ER -

In vivo processing and antibiotic activity of microcin B17 analogs with varying ring content and altered bisheterocyclic sites

Abstract

Funding

Keywords

ASJC Scopus subject areas

Access to Document

Other files and links

Fingerprint

Cite this