What is UV survival curve?
The survival curve (Fig. 1) shows that there was a steady decrease in survival with increasing exposure to UV. Survival was described as the percentage of cells originally plated that survived the UV treatment.
What is UV mutagenesis?
Abstract. Ultraviolet (UV) light induces specific mutations in the cellular and skin genome such as UV-signature and triplet mutations, the mechanism of which has been thought to involve translesion DNA synthesis (TLS) over UV-induced DNA base damage.
How does time of UV light exposure effect bacterial survival?
We compared the number of CFUs on plates exposed to UV for 24 and 48 hours to that of the control plates. The growth patterns reveal that the longer the period of UV exposure, the greater the decrease in the number of CFUs. 3) UV laboratory lights of short wavelengths are capable of inhibiting bacterial growth.
Which type of effect is observed in organisms after UV treatment?
The principal inactivating effect of UV irradiation is the formation of photoproducts in DNA. Of these photoproducts, the most important is the pyrimidine dimer formed between adjacent pyrimidine molecules on the same strand of DNA, which can interrupt both the transcription and the replication of the DNA.
What is survival curve in sterilization?
A cell survival curve is a curve used in radiobiology. It depicts the relationship between the fraction of cells retaining their reproductive integrity and the absorbed dose of radiation. Conventionally, the surviving fraction is depicted on a logarithmic scale, and is plotted on the y-axis against dose on the x-axis.
What does a cell survival curve describe?
A cell survival curve describes the relationship between the absorbed dose of radiation and the proportion of cells that survive in the sense that they are able to grow into a colony, thereby demonstrating retention of their reproductive integrity.
How does UV mutagenesis work?
Ultraviolet light (UV) is a strong mutagen (in the wavelength that DNA absorbs, roughly 225-300 nm) and primarily generates dimers between adjacent pyrimidine bases on the same DNA strand. These dimers cause the strand to buckle, disrupting normal base pairing.
What type of radiation is UV?
Ultraviolet (UV) radiation is a form of non-ionizing radiation that is emitted by the sun and artificial sources, such as tanning beds.
How do bacteria survive UV radiation?
Bacteria, especially extremophiles inhabiting harsh environments permanently exposed to damaging solar radiation, have evolved different strategies to cope with UV stress, mainly relying on efficient DNA repair mechanisms and/or active defense against UV-induced oxidative stress, and consequently need to tightly …