Inhibition by 1,10-phenanthroline of the breakdown of peptides by rumen bacteria and protozoa

R J Wallace, C J Newbold, N McKain

Research output: Contribution to journalArticleResearchpeer-review

9 Citations (Scopus)

Abstract

The rate of peptide breakdown in the rumen frequently exceeds the rate at which the amino acids released can be used for microbial growth. The final step in this often wasteful process involves the cleavage of dipeptides. The main rumen bacterial species with high dipeptidase activity, Prevotella ruminicola, Fibrobacter succinogenes, Lachnospira multipara and Megasphaera elsdenii, had activities which were inhibited > 95% by 1,10-phenanthroline, a chelator of divalent metal ions and metalloprotease inhibitor. Dipeptidase activity in digesta taken from the rumen of sheep decreased by 33% in the presence of 1,10-phenanthroline, while mixed bacteria from the same samples were inhibited by 80% and the activity of mixed protozoa decreased by only 15%. Thus a substantial amount of dipeptide breakdown appears to be due to ciliate protozoa in the mixed population. Extensive washing of the protozoa increased the sensitivity of protozoal dipeptidase activity to 1,10-phenanthroline, suggesting that protozoa too have a metallo-dipeptidase activity but that it is normally protected from inhibition by 1,10-phenanthroline. Breakdown of the pentapeptide, Ala5, was also inhibited 27% by 1,10-phenanthroline in the mixed population, and when Trypticase, a pancreatic casein hydrolysate containing a mixture of oligopeptides, dipeptides and amino acids, was incubated with rumen fluid, the production of ammonia and free amino groups was inhibited 71% by 1,10-phenanthroline. It was concluded that metal ion chelation inhibits oligopeptidase and dipeptidase activities of rumen micro-organisms and may be a means of controlling ammonia production from peptides in the rumen.

Original languageEnglish
Pages (from-to)425-30
Number of pages6
JournalJournal of Applied Microbiology
Volume80
Issue number4
Publication statusPrint publication - Apr 1996
Externally publishedYes

Fingerprint

Rumen
Bacteria
Peptides
Dipeptides
Ammonia
Prevotella ruminicola
Fibrobacter
Metals
Ions
Amino Acids
Oligopeptides
Metalloproteases
Chelating Agents
Population
1,10-phenanthroline
Sheep
dipeptidase
Growth

Keywords

  • Ammonia/metabolism
  • Animals
  • Bacteria/drug effects
  • Chelating Agents/pharmacology
  • Dipeptidases/drug effects
  • Eukaryota/drug effects
  • Peptides/metabolism
  • Phenanthrolines/pharmacology
  • Protease Inhibitors/pharmacology
  • Rumen/microbiology
  • Sheep

Cite this

@article{07f010830a1547bcb33abd3d3968a94d,
title = "Inhibition by 1,10-phenanthroline of the breakdown of peptides by rumen bacteria and protozoa",
abstract = "The rate of peptide breakdown in the rumen frequently exceeds the rate at which the amino acids released can be used for microbial growth. The final step in this often wasteful process involves the cleavage of dipeptides. The main rumen bacterial species with high dipeptidase activity, Prevotella ruminicola, Fibrobacter succinogenes, Lachnospira multipara and Megasphaera elsdenii, had activities which were inhibited > 95{\%} by 1,10-phenanthroline, a chelator of divalent metal ions and metalloprotease inhibitor. Dipeptidase activity in digesta taken from the rumen of sheep decreased by 33{\%} in the presence of 1,10-phenanthroline, while mixed bacteria from the same samples were inhibited by 80{\%} and the activity of mixed protozoa decreased by only 15{\%}. Thus a substantial amount of dipeptide breakdown appears to be due to ciliate protozoa in the mixed population. Extensive washing of the protozoa increased the sensitivity of protozoal dipeptidase activity to 1,10-phenanthroline, suggesting that protozoa too have a metallo-dipeptidase activity but that it is normally protected from inhibition by 1,10-phenanthroline. Breakdown of the pentapeptide, Ala5, was also inhibited 27{\%} by 1,10-phenanthroline in the mixed population, and when Trypticase, a pancreatic casein hydrolysate containing a mixture of oligopeptides, dipeptides and amino acids, was incubated with rumen fluid, the production of ammonia and free amino groups was inhibited 71{\%} by 1,10-phenanthroline. It was concluded that metal ion chelation inhibits oligopeptidase and dipeptidase activities of rumen micro-organisms and may be a means of controlling ammonia production from peptides in the rumen.",
keywords = "Ammonia/metabolism, Animals, Bacteria/drug effects, Chelating Agents/pharmacology, Dipeptidases/drug effects, Eukaryota/drug effects, Peptides/metabolism, Phenanthrolines/pharmacology, Protease Inhibitors/pharmacology, Rumen/microbiology, Sheep",
author = "Wallace, {R J} and Newbold, {C J} and N McKain",
year = "1996",
month = "4",
language = "English",
volume = "80",
pages = "425--30",
journal = "Journal of Applied Microbiology",
issn = "1364-5072",
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Inhibition by 1,10-phenanthroline of the breakdown of peptides by rumen bacteria and protozoa. / Wallace, R J; Newbold, C J; McKain, N.

In: Journal of Applied Microbiology, Vol. 80, No. 4, 04.1996, p. 425-30.

Research output: Contribution to journalArticleResearchpeer-review

TY - JOUR

T1 - Inhibition by 1,10-phenanthroline of the breakdown of peptides by rumen bacteria and protozoa

AU - Wallace, R J

AU - Newbold, C J

AU - McKain, N

PY - 1996/4

Y1 - 1996/4

N2 - The rate of peptide breakdown in the rumen frequently exceeds the rate at which the amino acids released can be used for microbial growth. The final step in this often wasteful process involves the cleavage of dipeptides. The main rumen bacterial species with high dipeptidase activity, Prevotella ruminicola, Fibrobacter succinogenes, Lachnospira multipara and Megasphaera elsdenii, had activities which were inhibited > 95% by 1,10-phenanthroline, a chelator of divalent metal ions and metalloprotease inhibitor. Dipeptidase activity in digesta taken from the rumen of sheep decreased by 33% in the presence of 1,10-phenanthroline, while mixed bacteria from the same samples were inhibited by 80% and the activity of mixed protozoa decreased by only 15%. Thus a substantial amount of dipeptide breakdown appears to be due to ciliate protozoa in the mixed population. Extensive washing of the protozoa increased the sensitivity of protozoal dipeptidase activity to 1,10-phenanthroline, suggesting that protozoa too have a metallo-dipeptidase activity but that it is normally protected from inhibition by 1,10-phenanthroline. Breakdown of the pentapeptide, Ala5, was also inhibited 27% by 1,10-phenanthroline in the mixed population, and when Trypticase, a pancreatic casein hydrolysate containing a mixture of oligopeptides, dipeptides and amino acids, was incubated with rumen fluid, the production of ammonia and free amino groups was inhibited 71% by 1,10-phenanthroline. It was concluded that metal ion chelation inhibits oligopeptidase and dipeptidase activities of rumen micro-organisms and may be a means of controlling ammonia production from peptides in the rumen.

AB - The rate of peptide breakdown in the rumen frequently exceeds the rate at which the amino acids released can be used for microbial growth. The final step in this often wasteful process involves the cleavage of dipeptides. The main rumen bacterial species with high dipeptidase activity, Prevotella ruminicola, Fibrobacter succinogenes, Lachnospira multipara and Megasphaera elsdenii, had activities which were inhibited > 95% by 1,10-phenanthroline, a chelator of divalent metal ions and metalloprotease inhibitor. Dipeptidase activity in digesta taken from the rumen of sheep decreased by 33% in the presence of 1,10-phenanthroline, while mixed bacteria from the same samples were inhibited by 80% and the activity of mixed protozoa decreased by only 15%. Thus a substantial amount of dipeptide breakdown appears to be due to ciliate protozoa in the mixed population. Extensive washing of the protozoa increased the sensitivity of protozoal dipeptidase activity to 1,10-phenanthroline, suggesting that protozoa too have a metallo-dipeptidase activity but that it is normally protected from inhibition by 1,10-phenanthroline. Breakdown of the pentapeptide, Ala5, was also inhibited 27% by 1,10-phenanthroline in the mixed population, and when Trypticase, a pancreatic casein hydrolysate containing a mixture of oligopeptides, dipeptides and amino acids, was incubated with rumen fluid, the production of ammonia and free amino groups was inhibited 71% by 1,10-phenanthroline. It was concluded that metal ion chelation inhibits oligopeptidase and dipeptidase activities of rumen micro-organisms and may be a means of controlling ammonia production from peptides in the rumen.

KW - Ammonia/metabolism

KW - Animals

KW - Bacteria/drug effects

KW - Chelating Agents/pharmacology

KW - Dipeptidases/drug effects

KW - Eukaryota/drug effects

KW - Peptides/metabolism

KW - Phenanthrolines/pharmacology

KW - Protease Inhibitors/pharmacology

KW - Rumen/microbiology

KW - Sheep

M3 - Article

VL - 80

SP - 425

EP - 430

JO - Journal of Applied Microbiology

JF - Journal of Applied Microbiology

SN - 1364-5072

IS - 4

ER -