Nitrification plays a crucial role in global nitrogen cycling and treatment processes. However, the relationships between the nitrifier guilds of ammonia-oxidizing bacteria (AOB) and nitrite-oxidizing bacteria (NOB) are still poorly understood, especially in freshwater habitats. This study examined the physiological interactions between the AOB and NOB present in a freshwater aquarium biofilter...

An account has been given elsewhere of the successful isolation of physiological x-ray mutants of Azotobacter agilis with genetic blocks in the substrate oxidation mechanisms (1). The present paper deals in greater detail with a mutant strain, designated A13, that was isolated as a variant unable to grow on glucose, and gives the methods used to characterize the particular deficiency responsibl...

We studied the parasitism by larvae of the chigger mite Eutrombicula alfreddugesi on the lizard community of Restinga de Jurubatiba, Rio de Janeiro State, Southeastern Brazil. We investigated the patterns of infestation (prevalence and intensity) of chigger mites in four sympatric lizards: Tropidurus torquatus, Mabuya agilis, M. macrorhyncha and Cnemidophorus littoralis. All lizards collected w...

BACKGROUND To date, the only estimate of the heritability of telomere length in wild populations comes from humans. Thus, there is a need for analysis of natural populations with respect to how telomeres evolve. METHODOLOGY/PRINCIPAL FINDINGS Here, we show that telomere length is heritable in free-ranging sand lizards, Lacerta agilis. More importantly, heritability estimates analysed within, ...