Open AccessCompetition between oral Streptococcus species in the chemostat under alternating conditions of glucose limitation and excess
Author(s) -
Hoeven J.S.,
Jong M.H.,
Camp P.J.M.,
Kieboom C.W.A.
Publication year - 1985
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/j.1574-6968.1985.tb01174.x
Subject(s) - streptococcus mutans , chemostat , streptococcus milleri , sucrose , microbiology and biotechnology , streptococcus , competition (biology) , biology , food science , biochemistry , bacteria , ecology , genetics
Oral Streptococcus species experience carbohydrate limitation interrupted by periods of substrate excess following food intake by the host. To investigate the competitiveness of various streptococcal species under fluctuating carbohydrate supply, 2‐membered chemostat cultures were run. Under continuous limitation of glucose or sucrose, all 6 Streptococcus mutans test strains were outcompeted by Streptococcus sanguis P4A7 or Streptococcus milleri B448. This indicated that S. mutans had a lower affinity for glucose and sucrose than S. sanguis and S. milleri . Mixed cultures were then subjected to hourly pulses with glucose. Under these conditions S. mutans Ny344 competed successfully with S. milleri B448, but still lost the competition against S. sanguis P4A7. The streptococci responded to pulses by taking up glucose at the maximum rate almost instantaneously. S. sanguis P4A7 had the highest rate of glucose uptake while the q max value of S. mutans Ny344 was higher than that of S. milleri B448. This suggested a causal relationship between q max and competitiveness.