Properties of ionophore-resistant Bacteroides ruminicola enriched by cultivation in the presence of tetronasin

C J Newbold, R J Wallace, N D Watt

Research output: Contribution to journalArticle

27 Citations (Scopus)

Abstract

Bacteroides ruminicola M384 was grown in the presence of increasing concentrations of tetronasin, an ionophore that has been developed as a feed additive for ruminants. The resulting culture, B. ruminicola M384/TnR, was then maintained in medium containing 0.1 microgram tetronasin/ml. Growth of the parent strain was eliminated by the addition of 0.1 micrograms tetronasin/ml, but the growth rate of B. ruminicola M384/TnR, which grew more slowly than the parent strain, was unaffected by adding tetronasin. Bacteroides ruminicola M384/TnR retained its resistance to tetronasin even after repeated subculture in the absence of the ionophore, suggesting that a mutation had occurred. The absence of plasmids in individual colonies of B. ruminicola M384/TnR implied that the mutation was chromosomal. Bacteroides ruminicola M384/TnR was also more resistant to the ionophores monensin and lasalocid and, to a lesser degree, to the antibiotic avoparcin than B. ruminicola M384. Binding of [14C]tetronasin to B. ruminicola M384/TnR was lower than binding of the ionophore to the parent stain, and this difference was eliminated by washing cells with EDTA. The peptidolytic activity of B. ruminicola M384 towards triphenylalanine (Mr = 460) was unaffected in B. ruminicola M384/TnR, but the rate of breakdown tetraphenylalanine (Mr = 607) was decreased. This difference was also abolished by EDTA. It was concluded that growth of B. ruminicola in the presence of tetronasin resulted in a mutation affecting the permeability of the cell envelope, such that permeation of tetronasin and molecules of a similar size (Mr = 628) was decreased.

Original languageEnglish
Pages (from-to)65-70
Number of pages6
JournalJournal of Applied Microbiology
Volume72
Issue number1
Publication statusPrint publication - Jan 1992
Externally publishedYes

Fingerprint

Bacteroides
Ionophores
Edetic Acid
Mutation
Growth
Lasalocid
Monensin
tetronasin
Ruminants
Permeability
Plasmids
Coloring Agents
Anti-Bacterial Agents

Keywords

  • Animals
  • Anti-Bacterial Agents/pharmacology
  • Bacteroides/drug effects
  • Cell Membrane Permeability/genetics
  • Chromosomes, Bacterial
  • Drug Resistance, Microbial/genetics
  • Furans/pharmacology
  • Glycopeptides/pharmacology
  • Ionophores/pharmacology
  • Lasalocid/pharmacology
  • Monensin/pharmacology
  • Mutation
  • Plasmids
  • Sheep

Cite this

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title = "Properties of ionophore-resistant Bacteroides ruminicola enriched by cultivation in the presence of tetronasin",
abstract = "Bacteroides ruminicola M384 was grown in the presence of increasing concentrations of tetronasin, an ionophore that has been developed as a feed additive for ruminants. The resulting culture, B. ruminicola M384/TnR, was then maintained in medium containing 0.1 microgram tetronasin/ml. Growth of the parent strain was eliminated by the addition of 0.1 micrograms tetronasin/ml, but the growth rate of B. ruminicola M384/TnR, which grew more slowly than the parent strain, was unaffected by adding tetronasin. Bacteroides ruminicola M384/TnR retained its resistance to tetronasin even after repeated subculture in the absence of the ionophore, suggesting that a mutation had occurred. The absence of plasmids in individual colonies of B. ruminicola M384/TnR implied that the mutation was chromosomal. Bacteroides ruminicola M384/TnR was also more resistant to the ionophores monensin and lasalocid and, to a lesser degree, to the antibiotic avoparcin than B. ruminicola M384. Binding of [14C]tetronasin to B. ruminicola M384/TnR was lower than binding of the ionophore to the parent stain, and this difference was eliminated by washing cells with EDTA. The peptidolytic activity of B. ruminicola M384 towards triphenylalanine (Mr = 460) was unaffected in B. ruminicola M384/TnR, but the rate of breakdown tetraphenylalanine (Mr = 607) was decreased. This difference was also abolished by EDTA. It was concluded that growth of B. ruminicola in the presence of tetronasin resulted in a mutation affecting the permeability of the cell envelope, such that permeation of tetronasin and molecules of a similar size (Mr = 628) was decreased.",
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author = "Newbold, {C J} and Wallace, {R J} and Watt, {N D}",
year = "1992",
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Properties of ionophore-resistant Bacteroides ruminicola enriched by cultivation in the presence of tetronasin. / Newbold, C J; Wallace, R J; Watt, N D.

In: Journal of Applied Microbiology, Vol. 72, No. 1, 01.1992, p. 65-70.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Properties of ionophore-resistant Bacteroides ruminicola enriched by cultivation in the presence of tetronasin

AU - Newbold, C J

AU - Wallace, R J

AU - Watt, N D

PY - 1992/1

Y1 - 1992/1

N2 - Bacteroides ruminicola M384 was grown in the presence of increasing concentrations of tetronasin, an ionophore that has been developed as a feed additive for ruminants. The resulting culture, B. ruminicola M384/TnR, was then maintained in medium containing 0.1 microgram tetronasin/ml. Growth of the parent strain was eliminated by the addition of 0.1 micrograms tetronasin/ml, but the growth rate of B. ruminicola M384/TnR, which grew more slowly than the parent strain, was unaffected by adding tetronasin. Bacteroides ruminicola M384/TnR retained its resistance to tetronasin even after repeated subculture in the absence of the ionophore, suggesting that a mutation had occurred. The absence of plasmids in individual colonies of B. ruminicola M384/TnR implied that the mutation was chromosomal. Bacteroides ruminicola M384/TnR was also more resistant to the ionophores monensin and lasalocid and, to a lesser degree, to the antibiotic avoparcin than B. ruminicola M384. Binding of [14C]tetronasin to B. ruminicola M384/TnR was lower than binding of the ionophore to the parent stain, and this difference was eliminated by washing cells with EDTA. The peptidolytic activity of B. ruminicola M384 towards triphenylalanine (Mr = 460) was unaffected in B. ruminicola M384/TnR, but the rate of breakdown tetraphenylalanine (Mr = 607) was decreased. This difference was also abolished by EDTA. It was concluded that growth of B. ruminicola in the presence of tetronasin resulted in a mutation affecting the permeability of the cell envelope, such that permeation of tetronasin and molecules of a similar size (Mr = 628) was decreased.

AB - Bacteroides ruminicola M384 was grown in the presence of increasing concentrations of tetronasin, an ionophore that has been developed as a feed additive for ruminants. The resulting culture, B. ruminicola M384/TnR, was then maintained in medium containing 0.1 microgram tetronasin/ml. Growth of the parent strain was eliminated by the addition of 0.1 micrograms tetronasin/ml, but the growth rate of B. ruminicola M384/TnR, which grew more slowly than the parent strain, was unaffected by adding tetronasin. Bacteroides ruminicola M384/TnR retained its resistance to tetronasin even after repeated subculture in the absence of the ionophore, suggesting that a mutation had occurred. The absence of plasmids in individual colonies of B. ruminicola M384/TnR implied that the mutation was chromosomal. Bacteroides ruminicola M384/TnR was also more resistant to the ionophores monensin and lasalocid and, to a lesser degree, to the antibiotic avoparcin than B. ruminicola M384. Binding of [14C]tetronasin to B. ruminicola M384/TnR was lower than binding of the ionophore to the parent stain, and this difference was eliminated by washing cells with EDTA. The peptidolytic activity of B. ruminicola M384 towards triphenylalanine (Mr = 460) was unaffected in B. ruminicola M384/TnR, but the rate of breakdown tetraphenylalanine (Mr = 607) was decreased. This difference was also abolished by EDTA. It was concluded that growth of B. ruminicola in the presence of tetronasin resulted in a mutation affecting the permeability of the cell envelope, such that permeation of tetronasin and molecules of a similar size (Mr = 628) was decreased.

KW - Animals

KW - Anti-Bacterial Agents/pharmacology

KW - Bacteroides/drug effects

KW - Cell Membrane Permeability/genetics

KW - Chromosomes, Bacterial

KW - Drug Resistance, Microbial/genetics

KW - Furans/pharmacology

KW - Glycopeptides/pharmacology

KW - Ionophores/pharmacology

KW - Lasalocid/pharmacology

KW - Monensin/pharmacology

KW - Mutation

KW - Plasmids

KW - Sheep

M3 - Article

C2 - 1541602

VL - 72

SP - 65

EP - 70

JO - Journal of Applied Microbiology

JF - Journal of Applied Microbiology

SN - 1364-5072

IS - 1

ER -