BACTERIOLOGY OF FERROMANGANESE NODULES FROM THE INDIAN-OCEAN

Bacteriological investigations of the ferromanganese nodules collected from the Indian Ocean indicate that the microbial populations associated with the nodules are, in general, comparable to those of the Pacific and Atlantic Oceans. Both Mn(II)-oxidizing and MnO//2-reducing psychrotrophic bacteria were present in the nodules. Members of Vibrio, Enterobacteriaceae, Bacillus, Micrococcus, Staphylococcus, Arthrobacter, and coryneforms were encountered in the present study. Most of the isolates were able to grow on a wide range of sodium chloride concentrations (0 to 10%). The isolates elaborated a number of hydrolytic enzymes, namely, amylase, gelatinase, lipase, and phosphatase. The dominance of the gram-positive group is attributed to terrigenous influences.