The Occurrence of Marine Actinomycetes in Texas Gulf Coast Substrates

Abstract

The aquatic actinomycetes as a discrete habitat group, comprise a group that has been more or less neglected; a greater proportion of actinomnycologic research has been concentrated on the soil and pathogenic forms. This is a natural development as the latter are important as pathogens and producers of antibiotics. However, in 1950 Silvey et al. correlated noxious tastes and odors in surface water supplies with the by-products of fresh water (glykophilic) actinomycetes. Thus the aquatic forms became economically important and worthy of extensive study. Previously, algae had been considered to be the offending organisms even though no algal by-products had been isolated and diluted in odor-free water to duplicate the unpalatable musty, woody, earthy or hay-like tastes in municipal waters. The resultant series of studies on the fresh water forms eventually created an interest in the marine strains. The fresh water studies stressed the odor and taste production problem, control, and limnology with notes on taxonomic, morphologic, and cultural characteristics (Silvey and Roach, 1953; 1956). In 1958, Roach and Silvey reported on the morphology and life cycle of a number of fresh water isolates and found that many produced both lateral and chain spores on the same secondary hyphae. This observation was of interest since those actinomycetes that produce lateral spores are placed in Micromonospora and those that produce chain spores, in Streptomyces. In 1956, a halophytic actinomycete was obtained from a sample of Cladophora from an intertidal pool with a salinity of 35 ppt from Bray's Island, North Carolina. This isolation, together with another from macerated Sargassum taken from the Gulf of Mexico near Galveston, Texas, plus the fact that actinomycetic odors are commonly observed in the estuaries or the lagoons of the Gulf, indicated that the marine habitats should be investigated. There was always the possibility that the activities of the marine actinomycetes would not be too different from those of the forms which had been isolated from soil, fresh water, and composts. The work was commenced in 1957 with the viewpoint of sampling the Texas Gulf Coast, concentrating on isolation and then investigating the morphology, degradatory activities, odor production and pathogenicity of the resultant isolates. In 1957, a literature on the marine actinomycetes was sparse. There were isolated reports, mostly from general studies of marine