Random mtDNA mutations modulate proliferation capacity in mouse embryonic fibroblasts.

An increase in mtDNA mutation load leads to a loss of critical cells in different tissues thereby contributing to the physiological process of organismal ageing. Additionally, the accumulation of senescent cells that display changes in metabolic function might act in an active way to further disrupt the normal tissue function. We believe that this could be the important link missing in our understanding of the molecular mechanisms of premature ageing in the mtDNA mutator mice.

Caenorhabditis elegans as a model system for mtDNA replication defects.

Since the isolation and physical characterization of mammalian mitochondrial DNA (mtDNA) over 35 years ago, numerous studies have been conducted in order to understand its structure and properties, including mode of mtDNA replication and transcription. Even today, the mode of mtDNA replication is still a matter of intense debate. We believe that Caenorhabditis elegans holds the promise of identifying molecular mechanisms of mitochondrial replication.

Mitochondrial energy metabolism and ageing.

Ageing can be defined as "a progressive, generalized impairment of function, resulting in an increased vulnerability to environmental challenge and a growing risk of disease and death". Ageing is likely a multifactorial process caused by accumulated damage to a variety of cellular components. During the last 20 years, gerontological studies have revealed different molecular pathways involved in the ageing process and pointed out mitochondria as one of the key regulators of longevity.

Mitochondrial DNA level, but not active replicase, is essential for Caenorhabditis elegans development.

A number of studies showed that the development and the lifespan of Caenorhabditis elegans is dependent on mitochondrial function. In this study, we addressed the role of mitochondrial DNA levels and mtDNA maintenance in development of C. elegans by analyzing deletion mutants for mitochondrial polymerase gamma (polg-1(ok1548)).

Streptomyces durmitorensis sp. nov., a producer of an FK506-like immunosuppressant.

Screening of soil samples from the Durmitor National Park, Serbia and Montenegro, for strains producing immunosuppressants with a similar mechanism of action to FK506 resulted in the isolation of the actinomycete strain MS405(T). Isolate MS405(T) was found to have morphological and phenotypic properties that were consistent with its classification as a Streptomyces strain. The DNA G+C content of strain MS405(T) was 72 mol%.