Determination of diversity of actinomycete in forest soil subject to different blood groups; Classical approaches before metagenomic

Abstract

Objective: Forensic microbiology is the developing field of forensic science. Forensic microbiologist can use trace evidence to match people to crime scenes, to investigate bioterrorism incidents, and to determine cause and time of death. In recent years, important studies on the environmental microbiota have been carried out. These studies can be associated with many legally valuable data as well as being related to the microbiota of environmental events. Actinobacteria are gram-positive micelle bacteria with enormous diversity, common in soil, and have high economic value. So far 47 families and 711 species of Actinobacteria were isolated and identified in variety of habitats. Increasing forensic studies in recent years show that microbial profiles can be used as evidence. Methods: In this study, actinobacteria were isolated from forest soil samples exposed to eight different blood groups for two weeks and control group. Genomic DNA isolation from colonies selected by considering comparative colony morphology, PCR amplification targetted 16S rRNA and sequence analysis were carried. Results: A total of five Actinobacteria type bacteria (three Micromonospora sp., one is Streptomyces sp., and one Actinomadura sp.) were obtained from the soil samples mixed with the B Rh (+) blood group in the 7th day. No Actinobacteria growth was observed neither in the control group nor in the soils to which other blood groups were added. According to the p-distance values of all isolates, they were determined as subspecies rather than a new species. Conclusion: This is a preliminary study to identify bacterial communities that may be present and differ in soil exposed to blood. The inability to isolate Actinobacteria from most of the soil samples may be due to the chemical or enzymatical properties of the bloods that can degrade the bacterial spores. In the further studies, different media and genomic techniques should be tried in different types of soils. © (2023), (Refik Saydam National Public Health Agency (RSNPHA)). All Rights Reserved.