He was skeptical of referring to them as microbodies because, as he noted, "too little is known of their enzyme complement and of their role in the physiology of the liver cells to substantiate a proposal at the present time". He suggested that these enzymes belonged to the same cell organelle, but different from previously known organelles. But it would take some years before he publicised his hypothesis, as strong evidences were still lacking. In 1955 his team demonstrated similar cell fractions with same biochemical properties from the ciliated protozoan Tetrahymena pyriformis, from which it was indicated that these particles were new cell organelles unrelated to mitochondria. He presented his discovery at a meeting of the American Society for Cell Biology in 1955, and formally published in 1966 in which he created the name peroxisomes for the organelles as they are involved in peroxidase reactions. In 1968 he achieved the first large-scale preparation of peroxisomes, confirming that l-α hydroxyacid oxidase, d-amino acid oxidase, and catalase were all the unique enzymes of peroxisomes.