The biochemical and physiological basis of density heterogeneity in Renografin of @entity3881 W23 spores was determined by analysis of metals, macromolecules, and @entity10044 in the two density classes of the population. Germination rate and heat resistance were measured in both density classes. Atomic absorption spectrophotometry revealed that heavy spores (density = 1.335 g/ml) have 30% more @entity460 than light spores (density = 1.290 g/ml). Other metals found in greater amounts in heavy spores were @entity921 and @entity972 . However, light spores had more @entity1372 than heavy spores. The amounts of @entity3363 , nucleic acids, and proteins were the same in both types of spores, but light spores contained more lipids, whereas heavy spores had 30% more @entity10044 than light spores. @entity460 and lipid were excluded as causes of the heterogeneity in density in that alteration of their contents in spores did not detectably affect the density of these spores. Spores of two densities were genetically similar. Furthermore, light density spores arose earlier during sporulation than heavy spores as determined by releasing refractile forespores at various times during sporulation. We concluded that light spores represent an incomplete stage in development because they became heavy when reinoculated into spent sporulation medium. This must involve the additional accretion or synthesis of @entity10044 .

Buoyant density heterogeneity in spores of XXXX : biochemical and physiological basis.

@entity10044 :: ('MESH:C004860', 'Chemical') :: ['dipicolinic acid'] @entity921 :: ('MESH:D008345', 'Chemical') :: ['manganese'] @entity1372 :: ('MESH:D012964', 'Chemical') :: ['sodium'] @entity460 :: ('MESH:D002118', 'Chemical') :: ['calcium', 'Calcium'] @entity972 :: ('MESH:D011188', 'Chemical') :: ['potassium'] @entity3881 :: ('1423', 'Species') :: ['Bacillus subtilis'] @entity3363 :: ('MESH:D002241', 'Chemical') :: ['carbohydrates']
@entity3881 :: (1423,Species) :: ['Bacillus subtilis']
