Typologie de bactéries prélevées devant le delta du Rhöne. Classification hiérarchique par une méthode d'agrégation suivant la variance. Clustering of Bacteria Isolated Seaward from the Rhǒne Outlet. Hierarchical Classification Using the Method of Aggregation According to Variance

✍ Scribed by Dr. B. R. Berland; Dr. D. J. Bonin; Dr. S. Y. Maestrini; Mr. J.-P. Durbec

• Publisher: John Wiley and Sons
• Year: 1976
• Tongue: English
• Weight: 955 KB
• Volume: 61
• Category: Article
• ISSN: 1434-2944
• DOI: 10.1002/iroh.19760610304

✦ Synopsis

Abstract

Bacteria isolated from surface sea waters, brackish waters and from algal cultures were studied to attempt a nutritional clustering. A hierarchical method, using aggregation according to variance, was used to compute the data. Six nutritional groups had been separated by differences in genus composition and nutritional characteristics. Groups range from one with bacteria which are poorly versatile, i.e. attach few different substances, and which grow on sugars, amino‐acids and organic acids without any selectivity, to one with bacteria which are versatile, and which attack numerous organic acids and amino‐acids, but only a few sugars. Bacteria from different origins are not spread randomly in the different clusters. Strains isolated from algal cultures are mainly associated with the lowest versatility; those isolated from the undiluted sea water are associated with the highest versatility. Bacteria from diluted sea waters appear to be intermediate in regard to their capability of using organic substances as their sole source of carbon. It also appears that organic acids provide individually the most discriminating substrates, i.e. the most useful for separating individual groups, but amino‐acids and organic acids, as a whole, are not easy to use in classification, because they are too heterogeneous. Sugar contribution to classification is almost nil.