Microorganisms

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Q 1.
	What follows is an account of a strange phenomenon observed and recorded by Captain N. J. Roberts and officers of M/V Shaftesbury on February 3, 1967 in the northern part of the South China sea. Can you offer any explanation as to what it might have been? The report reads, in part: "On a dark moonless night with good visibility a thin white line with about two degrees altitude was observed ahead. The line was estimated to be about five miles distant. Thirty minutes later the vessel passed from the normal dark water over a clear cut white line into whitish water, and breaking waves could not then be observed. The whole sea gradually was white from horizon to horizon. The water continued in this state for about six miles, and then a gradual change back to normal dirk water was observed. This took about three miles to occur, and breaking waves could once again be observed."
Q 2.
	I have been told that flesh and bones immersed in seawater are completely decomposed by enzymatic action in a relatively short time. Can you give me information on factors which control the rate of enzymatic action?
Q 3.
	Can you tell us why some quahog clams found on Fort Myers Beach this past summer contained a reddish colored liquid. Is this condition an indication of poison, or are the clams safe to eat?
Q 4.
	While diving off the west coast of Ireland, we found about 60 basking sharks on the seafloor, each one devoid of fins and liver--the work of local shark fishermen. A constant cloud of matter and gas drifted from each carcass to the surface 40 feet above, and shoals of small pollack were feeding among this and on the carcasses. Would you describe how fish decompose underwater, and also tell me if the above method of disposal could be classed fertilization or pollution?
Q 5.
	In reviewing literature about red tides, I note that in some cases dinoflagellates are referred to as animals and in other cases they are called plants. Which is correct?
Q 6.
	I have read that the dinoflagellate, Noctiluca, is luminescent and produces a so-called cold light in its body from an enzymatic reaction. Has any research been done toward possibly using this same type of substance in lighting systems for man?


_{-- a n s w e r s a b o u t M i c r o o r g a n i s m s --}
	Q&A 1.	What follows is an account of a strange phenomenon observed and recorded by Captain N. J. Roberts and officers of M/V Shaftesbury on February 3, 1967 in the northern part of the South China sea. Can you offer any explanation as to what it might have been? The report reads, in part: "On a dark moonless night with good visibility a thin white line with about two degrees altitude was observed ahead. The line was estimated to be about five miles distant. Thirty minutes later the vessel passed from the normal dark water over a clear cut white line into whitish water, and breaking waves could not then be observed. The whole sea gradually was white from horizon to horizon. The water continued in this state for about six miles, and then a gradual change back to normal dirk water was observed. This took about three miles to occur, and breaking waves could once again be observed." Philadelphia, Pennsylvania
	It is very difficult to explain the phenomenon observed by the Shaftesbury without having a sample of the water to study. Possibly what was seen was a bloom of bioluminescent algae. In the Indian Ocean, such blooms have been recorded as having an extent of over 20,000 square miles. The calming effect observed by the ship might have been due to oils released by the decomposition of some of the algae. The location of the ship at time of sighting is well within the latitudes at which such spectacular blooming is known to occur.
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	Q&A 2.	I have been told that flesh and bones immersed in seawater are completely decomposed by enzymatic action in a relatively short time. Can you give me information on factors which control the rate of enzymatic action? New York City, New York
	In water, degradation proceeds more rapidly than in air because decomposition products are continuously dissolved and moved from the site. The decomposition to which you refer is generally not caused by enzymatic action alone. It is almost always assisted by various scavenging organisms present in seawater, such as crabs, fishes, starfish, and a host of carnivorous invertebrates, some of which are not visible to the naked eye. They gather around such bonanzas to feast, and do effect a remarkably efficient cleanup.
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	Q&A 3.	Can you tell us why some quahog clams found on Fort Myers Beach this past summer contained a reddish colored liquid. Is this condition an indication of poison, or are the clams safe to eat? Coral Gables, Florida
	A definite answer would be impossible without having examined the specimens, but it is possible that the quahogs in question had simply ingested a substantial number of pigmented microorganisms. These might have been bacteria, or more probably brownish-red protozoa. When you next observe this phenomenon you might receive a more definite answer if you send a sample to the Bureau of Commercial Fisheries & Laboratory, Gulf Breeze, Florida, where a long-term study of algae and protozoa is being conducted. Red coloration is not at all rare in any of these filter feeders, and usually represents a concentration of reddish-hued food animals that have, for reasons not fully understood, appeared in tremendous numbers in the water. Consumers commonly reject reddish seafoods, but this startling phenomenon usually has no medical significance.
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	Q&A 4.	While diving off the west coast of Ireland, we found about 60 basking sharks on the seafloor, each one devoid of fins and liver--the work of local shark fishermen. A constant cloud of matter and gas drifted from each carcass to the surface 40 feet above, and shoals of small pollack were feeding among this and on the carcasses. Would you describe how fish decompose underwater, and also tell me if the above method of disposal could be classed fertilization or pollution? Belfast, Ireland
	In water, degradation proceeds more rapidly than in air because decomposition products are continuously dissolved and moved from the site. The decomposition to which you refer is generally not caused by enzymatic action alone. It is almost always assisted by various microorganisms such as bacteria, molds, and scavenging organisms present in seawater, such as crabs, fishes, starfish and a host of carnivorous invertebrates, some of which are invisible to the naked eye. They gather around such bonanzas to feast and do a remarkably efficient cleanup. In the case you described, the disposal would not be considered pollution because there was nothing foreign to the marine ecosystem involved. Strange Case of the Alvin Lunches: Bologna sandwiches, apples, and thermos bottles of soup recovered from the Alvin after she had been submerged for 11 months at 37 degrees Fahrenheit showed no visible deterioration, yet they all spoiled after a few more weeks in a laboratory refrigerator at the same temperature. Further experiments by Dr. Holger Jannasch and associates at Woods Hole Oceanographic Institution show that the pressure of 150 atmospheres must be the prime cause for inhibiting microbial growth and not the low temperature. They suggest that organic materials originating on land and dumped into the deep ocean will not readily be decomposed.
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	Q&A 5.	In reviewing literature about red tides, I note that in some cases dinoflagellates are referred to as animals and in other cases they are called plants. Which is correct? Columbus, Ohio
	Most of the flagellates, dinoflagellates included, have been a taxonomic problem. One of the prime distinctions normally made between the organisms known as plants and those called animals is that the former are autotrophic (they "build" their own food from inorganic materials available in the environment) and the latter are heterotrophic (they ingest existing organic material). The flagellated organisms fall into a sort of gray area. Some can and do make their own food but, at times, or under certain conditions, these species will feed on other organisms. Thus, in one case, they are "plants" while, in the second, they are "animals." At the same time, some species of dinoflagellates are strictly heterotrophic (e.g., Noctiluca), while others are strictly autotrophic. As a result, many systematists assign all of these organisms to a third major kingdom, the Protista. In the five-kingdom model proposed by Robert Whittaker (Science, 1969, 163:150-160), the Protista includes the dinoflagellates, golden algae, diatoms, photosynthetic flagellates, heterotrophic flagellates, amoebas, foraminiferans, parasitic sporozoans, and ciliates.
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	Q&A 6.	I have read that the dinoflagellate, Noctiluca, is luminescent and produces a so-called cold light in its body from an enzymatic reaction. Has any research been done toward possibly using this same type of substance in lighting systems for man? Fort Eustis, Virginia
	The reaction to which you refer involves a luminous material called luciferin which is accumulated by the dinoflagellate. To emit light, the animal triggers a chemical reaction in which the luciferin is oxidized by the enzyme luciferase (see "Luminous Creatures of the Sea," Sea Frontiers, Vol. 10, No. 3, July, 1964). Since heat is not emitted in the reaction, the light is called cold light. This biological method of producing cold light is referred to as bioluminescence. To produce light of a sufficient intensity to be useful to humans, large quantities of natural luciferin would be needed; therefore, it would not be commercially feasible to use this material. There are other chemical reactions, however, known as chemoluminescence, that do produce significant amounts of light, and they are used in the manufacture of light sticks or light wands. These devices are designed for underwater use or for use in situations in which incandescent, or hot light, is potentially hazardous (i.e., around gasoline or other volatile fluids). They are available in most dive shops and fishing supply stores.
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