20 mg l -1 . In seawater with 20 mg Zn 2+ 1 -1 zinc concentration in Acinetobacter CS 13 after
2 d of exposure was 4625 µg g -1 dry wt, corresponding to 0.46 % of dry wt. In glucoselimited chemostats, a concentration of 25 µg Cd 2+ 1 -1 already inhibited the growth of
Acinetobacter CS 13 (Tan, 1983). It is likely that Acinetobacter CS 13 is more sensitive to
zinc in minimal liquid medium than in seawater.
ACKNOWLEDGEMENTS
This work was supported in part by a grant from the Bundesministeriumfur Forschung und Technologie (MFU
0505 BO). The experiments in seawater aquariums were carried out at the Meeresstation Helgoland from the
Biologische Anstalt Helgoland. I am grateful for good facilities provided and for the helpful support given by J.
Holtmann and his colleagues. I am obliged to H. Westphal and K. Wohlert for preparing the figures and
photographs, and to M. Gomez for manuscript correction. My thanks are also due to Erika Allhusen and
Susanne Spahic for their technical assistance.
LANDRY M.R., L.W. HAAS and V.L. FAGERNESS, 1984. Dynamic of microbial plankton communities : experiments in Kaneohe Bay, Hawaii. Mar. Ecol. Prog. Ser. 16, 127-133.
LESSARD E.J. and J. McN. SIEBURTH, 1983. Survival of natural sewage populations of enteric bacteria in
diffusion and batch chambers in the marine environment. Appl. Environ. Microbiol. 45, 950-959.
Mc FETERS G.A. and D.G. STUART, 1972. Survival of coliform bacteria in natural waters : Field and laboratory
studies with membrane-filter chambers. Appl. Microbiol. 24, 805-811.
Mc FETERS G.A. and D.G. STUART, In situ studies using membrane filter chambers. In : Membrane filtration.
Applications, techniques, and problems, pp 481 -512. Ed. by B.J. Dutka, New York : Marcel Dekker, Inc. 1981.
NORDBRING-HERTZ B., 1983. Dialysis membrane technique for studying microbial interaction. Appl. Environ.
Microbiol. 45, 290-293.
PICKETT A. W. and A.C.R. DEAN, 1976. Cadmium and zinc sensivity and tolerance in Klebsiella (Aerobacter)
aerogenes. Microbiol. 15, 79-91.
PICKETT A.W. and A.C.R. DEAN , 1979. Cadmium and zinc sensitivity and tolerance in Bacillus subtilis subsp.
niger and in a Pseudomonas sp. Microbios 24, 51-64.
RHODES M.W., I.C. ANDERSON and H.I. KATOR , 1983. In situ development of sublethal stress in Escherichia
coli : Effects on enumeration. Appl. Environ. Microbiol. 45, 1870-1876 .
SAKSHAUG E. and A. JENSEN , 1978. The use of cage cultures in studies of the biochemistry and ecology of marine
phytoplankton. Oceanogr. Mar. Biol. Ann. Rev. 16, 81-106.
SCHULTZ J.S. and P. GERHARDT, 1969. Dialysis culture of microorganisms: Design, theory and results.
Bacteriol. Rev. 33, 1-47 (1969).
TAN T.L., 1983. Unbalanced growth of Acinetobacter CS 13 in glucose-limited chemostats caused by sublethal
CdCb concentrations. Mar. Biol. 76, 247-252.
VASCONCELOS G.J. and R.G. SWARTZ, 1976. Survival of bacteria in seawater using a diffusion chamber
apparatus in situ. Appl. Environ. Microbiol. 31, 913-920.
WINFREY M.R. and J.G. ZEIKUS, 1977. Effect of sulfate on carbon and electron flow during microbial
methanogenesis in freshwater sediments. Appl. Environ. Microbiol. 33, 275-281.
595
2 d of exposure was 4625 µg g -1 dry wt, corresponding to 0.46 % of dry wt. In glucoselimited chemostats, a concentration of 25 µg Cd 2+ 1 -1 already inhibited the growth of
Acinetobacter CS 13 (Tan, 1983). It is likely that Acinetobacter CS 13 is more sensitive to
zinc in minimal liquid medium than in seawater.
ACKNOWLEDGEMENTS
This work was supported in part by a grant from the Bundesministeriumfur Forschung und Technologie (MFU
0505 BO). The experiments in seawater aquariums were carried out at the Meeresstation Helgoland from the
Biologische Anstalt Helgoland. I am grateful for good facilities provided and for the helpful support given by J.
Holtmann and his colleagues. I am obliged to H. Westphal and K. Wohlert for preparing the figures and
photographs, and to M. Gomez for manuscript correction. My thanks are also due to Erika Allhusen and
Susanne Spahic for their technical assistance.
LANDRY M.R., L.W. HAAS and V.L. FAGERNESS, 1984. Dynamic of microbial plankton communities : experiments in Kaneohe Bay, Hawaii. Mar. Ecol. Prog. Ser. 16, 127-133.
LESSARD E.J. and J. McN. SIEBURTH, 1983. Survival of natural sewage populations of enteric bacteria in
diffusion and batch chambers in the marine environment. Appl. Environ. Microbiol. 45, 950-959.
Mc FETERS G.A. and D.G. STUART, 1972. Survival of coliform bacteria in natural waters : Field and laboratory
studies with membrane-filter chambers. Appl. Microbiol. 24, 805-811.
Mc FETERS G.A. and D.G. STUART, In situ studies using membrane filter chambers. In : Membrane filtration.
Applications, techniques, and problems, pp 481 -512. Ed. by B.J. Dutka, New York : Marcel Dekker, Inc. 1981.
NORDBRING-HERTZ B., 1983. Dialysis membrane technique for studying microbial interaction. Appl. Environ.
Microbiol. 45, 290-293.
PICKETT A. W. and A.C.R. DEAN, 1976. Cadmium and zinc sensivity and tolerance in Klebsiella (Aerobacter)
aerogenes. Microbiol. 15, 79-91.
PICKETT A.W. and A.C.R. DEAN , 1979. Cadmium and zinc sensitivity and tolerance in Bacillus subtilis subsp.
niger and in a Pseudomonas sp. Microbios 24, 51-64.
RHODES M.W., I.C. ANDERSON and H.I. KATOR , 1983. In situ development of sublethal stress in Escherichia
coli : Effects on enumeration. Appl. Environ. Microbiol. 45, 1870-1876 .
SAKSHAUG E. and A. JENSEN , 1978. The use of cage cultures in studies of the biochemistry and ecology of marine
phytoplankton. Oceanogr. Mar. Biol. Ann. Rev. 16, 81-106.
SCHULTZ J.S. and P. GERHARDT, 1969. Dialysis culture of microorganisms: Design, theory and results.
Bacteriol. Rev. 33, 1-47 (1969).
TAN T.L., 1983. Unbalanced growth of Acinetobacter CS 13 in glucose-limited chemostats caused by sublethal
CdCb concentrations. Mar. Biol. 76, 247-252.
VASCONCELOS G.J. and R.G. SWARTZ, 1976. Survival of bacteria in seawater using a diffusion chamber
apparatus in situ. Appl. Environ. Microbiol. 31, 913-920.
WINFREY M.R. and J.G. ZEIKUS, 1977. Effect of sulfate on carbon and electron flow during microbial
methanogenesis in freshwater sediments. Appl. Environ. Microbiol. 33, 275-281.
595