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Comparative analysis of 16s ribosomal rna typing and physiological traits within sporosarcina ureae
Sporosarcina ureae is a motile spore forming cocci that traditionally forms packets. The term sarcina is used to describe packets of cocci microorganisms that divide bilaterally, on two or three successive planes. Both physiological and partial 16S ribosomal RNA typing of the ATCC type strain places Sporosarcina ureae in the Bacillaceae family. A key characteristic of the family Bacillaceae is the rod shape and bacterial spore formation. Sporosarcina ureae nomenclature has changed as the result of morphological and biochemical observations. Thus a question arises as to which is a better predictor or tool for classification, physiology (Biolog®), 16S rRNA gene structure, DNA genome sequencing, or MALDI-TOF MS analysis. High throughput Pac Bio sequencing and Biolog® was completed on 6 of the 50+ strains from the California State University, Northridge (CSUN) collection based on extremes of urease activity. MALDI-TOF testing was completed on the entire collection while 16S rRNA sequencing was completed on 33 strains. Based on MALDI-TOF MS work, there are at least 9 different genera, 17 species and 6 strains of Sporosarcina present among the 59 while the 16S ribosomal sequencing found five clusters. Biolog® results created two clusters and reaffirmed nutritional work of Pregerson and Risen suggesting Sporosarcina utilizes the Hexose Monophosphate Pathway, Citric Acid Cycle, and Glyoxylate pathways. This study strongly supports the hypothesis that the 16S rRNA gene and physiological studies show a low degree of homology across geographically distributed isolates. The strongest agreement that we could find was between the PacBio 16S consensus sequence and MALDI-TOF MS for P33 and P37. This study also suggests a relatively ancient divergence between Sporosarcina (sarcina) and Bacillus (rod).