The non-sporeforming nocardioforms are found preponderantly in the open sea up to
about 2000 m. Their survival ability at greater depth appeared to be relatively low. But
they are best adapted for reproduction in marine environments up to moderate depths.
By a chemotaxonomic and numerical taxonomic assay the majority of the marine
nocardioform isolates could be assigned to the genus Rhodococcus and clearly differentiated from other known species of that genus. These organisms could be given species
status and referring to the exclusive occurrence of this taxon in the sea they were named
Rhodococcus marinonascens (Helmke E. and Weyland H. 1984). By this organism an
indigenous marine actinomycete could be made evident for the first time. Its niche is still
unknown.
ACKNOWLEDGEMENTS
Sincere thanks are due to all the individuals and institutes who kindly supported me during the survey of the
distribution of actinomycetes in the sediment of various sea areas. My gratitude also extends to the scientific
staffs, officers and crews of research vessels for all kinds of assistance at sea. Special thanks is due to the staff of
the Bacteriology Section of the IfM Bremerhaven. This work was supported by the Deutsche Forschungsgemeinschaft (DFG) and by the Bundesminister für Forschung und Technologie (BMFT).
CROSS T., 1981. Aquatic actinomycetes : a critical survey of the occurrence, growth and role of actinomycetes in
aquatic habitats.J.Appl. Bacteriology 50 : 397 - 423.
HELMKE E., 1980. Dr. thesis, Universität Braunschweig, Federal Republic of Germany, 1980.
HELMKE E., 1981. Growth of actinomycetes from marine and terrestrial origin under increased hydrostatic
pressure. Zentralbl. Bacteriol. Parasitenkd. Infektionskr. Hyg. Abt 1. Suppl. 11 : 321-327.
HELMKE E. and WEYLAND, H., 1984. Rhodococcus marinonascens sp.nov., an actinomycete from the sea. Int. J.
Syst. Bacteriol. 34 : 127 - 138.
KRISS A.E., MISHUSTINA I.E., MITKEVICH N. ZEMSTOVA E.V., 1967. Microbial populations of oceans and
seas. Edw. Arnold, Ltd. London.
OKAMI Y. and OKASAKI T., 1978. Actinomycetes in marine environments. In : Mordarski, M.and Jeljaszewicz,
J., (eds.) : Nocardia and Streptomyces, Gustav Fischer, Stuttgart, pp 145 - 151.
WALKER J.D. and COLLWELL R.R., 1975. Factors effecting enumeration and isolation of actinomycetes from
Chesapeake Bay and southeastern Atlantic ocean sediments. Marine Biology 30 : 193- 201.
WEYLAND H., 1969. Actinomycetes in North Sea and Atlantic ocean sediments.Nature 223, No. 5208 : 858.
WEYLAND H., 1981 a. Distribution of actinomycetes on the sea floor. Zentralbl. Bakteriol. Parasitenkd.
Infektionskr. Hyg. Abt.I Suppl. Il : 185 - 193.
WEYLAND H. 1981 b. Characteristics of actinomycetes isolated from marine sediments. Zentralbl. Bakteriol.
Parasitenkd. Infektionskr. Hyg. Abt 1 suppl 11. : 309 - 314.
ZOBELL C.E., 1946. Marine Microbiology. Chronica Botanica Co. Waltham Mass.
79
about 2000 m. Their survival ability at greater depth appeared to be relatively low. But
they are best adapted for reproduction in marine environments up to moderate depths.
By a chemotaxonomic and numerical taxonomic assay the majority of the marine
nocardioform isolates could be assigned to the genus Rhodococcus and clearly differentiated from other known species of that genus. These organisms could be given species
status and referring to the exclusive occurrence of this taxon in the sea they were named
Rhodococcus marinonascens (Helmke E. and Weyland H. 1984). By this organism an
indigenous marine actinomycete could be made evident for the first time. Its niche is still
unknown.
ACKNOWLEDGEMENTS
Sincere thanks are due to all the individuals and institutes who kindly supported me during the survey of the
distribution of actinomycetes in the sediment of various sea areas. My gratitude also extends to the scientific
staffs, officers and crews of research vessels for all kinds of assistance at sea. Special thanks is due to the staff of
the Bacteriology Section of the IfM Bremerhaven. This work was supported by the Deutsche Forschungsgemeinschaft (DFG) and by the Bundesminister für Forschung und Technologie (BMFT).
CROSS T., 1981. Aquatic actinomycetes : a critical survey of the occurrence, growth and role of actinomycetes in
aquatic habitats.J.Appl. Bacteriology 50 : 397 - 423.
HELMKE E., 1980. Dr. thesis, Universität Braunschweig, Federal Republic of Germany, 1980.
HELMKE E., 1981. Growth of actinomycetes from marine and terrestrial origin under increased hydrostatic
pressure. Zentralbl. Bacteriol. Parasitenkd. Infektionskr. Hyg. Abt 1. Suppl. 11 : 321-327.
HELMKE E. and WEYLAND, H., 1984. Rhodococcus marinonascens sp.nov., an actinomycete from the sea. Int. J.
Syst. Bacteriol. 34 : 127 - 138.
KRISS A.E., MISHUSTINA I.E., MITKEVICH N. ZEMSTOVA E.V., 1967. Microbial populations of oceans and
seas. Edw. Arnold, Ltd. London.
OKAMI Y. and OKASAKI T., 1978. Actinomycetes in marine environments. In : Mordarski, M.and Jeljaszewicz,
J., (eds.) : Nocardia and Streptomyces, Gustav Fischer, Stuttgart, pp 145 - 151.
WALKER J.D. and COLLWELL R.R., 1975. Factors effecting enumeration and isolation of actinomycetes from
Chesapeake Bay and southeastern Atlantic ocean sediments. Marine Biology 30 : 193- 201.
WEYLAND H., 1969. Actinomycetes in North Sea and Atlantic ocean sediments.Nature 223, No. 5208 : 858.
WEYLAND H., 1981 a. Distribution of actinomycetes on the sea floor. Zentralbl. Bakteriol. Parasitenkd.
Infektionskr. Hyg. Abt.I Suppl. Il : 185 - 193.
WEYLAND H. 1981 b. Characteristics of actinomycetes isolated from marine sediments. Zentralbl. Bakteriol.
Parasitenkd. Infektionskr. Hyg. Abt 1 suppl 11. : 309 - 314.
ZOBELL C.E., 1946. Marine Microbiology. Chronica Botanica Co. Waltham Mass.
79