PARTICULATE ORG-4NIC MATTER I N SEA WATER
65
Hence, while there may be marine bacteria that fall within this size
range in their normal vegetative state, some of them must have nonactive stages of a smaller size. Senescent stages are commonly reduced
in size. The writer can find no information as to whether any marine
bacteria are known to produce filterable " L phases ", although
certainly many of them are highly pleomorphic. Thus the existence
of viable, filterable bacteria in sea water is established beyond reasonable doubt, but the form in which they occur is open to question, and
their quantitative abundance is not known. They are possibly a small
percentage of the total biomass. The ATP analyses described by HolmHansen and Booth (1966), indicated that total biomass was essentially
in agreement with observed numbers of cells of normal size.
The situation described in long term experiments is clearly different,
but experimental procedures induce an artificial selection of filterable
forms and eliminate any bacteria that require special conditions such
as low temperature or high pressure. The ones that survive and
multiply in the experiments have a good chance of being suitable for
detection in plate counts.
Although these considerations supply a possible explanation for
astronomical numbers of bacteria despite the relatively low value for
particulate carbon, they do not provide much insight into the dynamics
of the situation. The early part of the experiments suggested a stable
state in both bacteria and particulate matter. The latter remained
more or less constant thereafter, although increasing slightly during
the final few weeks of some experiments, while the bacterial population
was anything but stable.
However, there is a question as to how many of these bacteria were
in an active physiological state. There was a small, continuing p o p -
lation of bacteria of normal size, which was readily detectable by
visual examination. One can postulate that these were existing on the
verge of senescence, some being able to divide normally and others
being transformed into smaller forms which gradually accumulated in
a viable but inactive state.
I n summary, the early stages of the so-called stable state seem
realistic in that carbon levels and bacterial counts approximate those
found in the sea. The later sequence of events remains realistic only with
respect to maintenance of a reasonably stable carbon level, and problems
involving dynamic relations with bacteria require further study by
more exacting methods. Here again, as in bubbling experimenfs,
there is a need for an examination of basic problems, preferably with
defined artificial media.
Moreover, the experiments are deficient in that data are largely
65
Hence, while there may be marine bacteria that fall within this size
range in their normal vegetative state, some of them must have nonactive stages of a smaller size. Senescent stages are commonly reduced
in size. The writer can find no information as to whether any marine
bacteria are known to produce filterable " L phases ", although
certainly many of them are highly pleomorphic. Thus the existence
of viable, filterable bacteria in sea water is established beyond reasonable doubt, but the form in which they occur is open to question, and
their quantitative abundance is not known. They are possibly a small
percentage of the total biomass. The ATP analyses described by HolmHansen and Booth (1966), indicated that total biomass was essentially
in agreement with observed numbers of cells of normal size.
The situation described in long term experiments is clearly different,
but experimental procedures induce an artificial selection of filterable
forms and eliminate any bacteria that require special conditions such
as low temperature or high pressure. The ones that survive and
multiply in the experiments have a good chance of being suitable for
detection in plate counts.
Although these considerations supply a possible explanation for
astronomical numbers of bacteria despite the relatively low value for
particulate carbon, they do not provide much insight into the dynamics
of the situation. The early part of the experiments suggested a stable
state in both bacteria and particulate matter. The latter remained
more or less constant thereafter, although increasing slightly during
the final few weeks of some experiments, while the bacterial population
was anything but stable.
However, there is a question as to how many of these bacteria were
in an active physiological state. There was a small, continuing p o p -
lation of bacteria of normal size, which was readily detectable by
visual examination. One can postulate that these were existing on the
verge of senescence, some being able to divide normally and others
being transformed into smaller forms which gradually accumulated in
a viable but inactive state.
I n summary, the early stages of the so-called stable state seem
realistic in that carbon levels and bacterial counts approximate those
found in the sea. The later sequence of events remains realistic only with
respect to maintenance of a reasonably stable carbon level, and problems
involving dynamic relations with bacteria require further study by
more exacting methods. Here again, as in bubbling experimenfs,
there is a need for an examination of basic problems, preferably with
defined artificial media.
Moreover, the experiments are deficient in that data are largely