Duration of Conservation of Plague Microbe (Yersinia pestis) Genes in Mammalian Bone Remains

Objective of this work was to determine the long-term preservation of Yersinia pestis DNA, detected by polymerase chain reaction (PCR) in the bone tissue of rodents, and to quantify content changes over time under the influence of biotic and abiotic factors. Materials and methods. After death of model animals infected with virulent Y. pestis strain, their skeletons were freed from soft tissues and placed in the environments where conditions were close to the natural ones. The study of bone remains for the presence of Y. pestis DNA fragments was held immediately after the death of the animals, and then, twice a year. Results and conclusions. The data obtained allow for dividing all the fossil remains of the fallen from plague infection mammals into three separate groups: with high, medium, and low content of bacteria. Further study demonstrates that reduction of Y. pestis DNA concentration in bone tissue of animals after six months of storage does not occur. After a year, a sharp decrease (100-fold) of observable material dilutions for which the identification of detected plasmids is still possible, is registered. After one and a half year of observation, the genes of plague microbe in the bones of experimental animals could not be found. In order to increase the information content of the study of this type of material put forward has been proposal to reestablish the system of observation sites to collect castings and bone remains of mammals. 

1. Novikov G.S. [Search of antigen fraction I as a method of epizooti- ological surveillance over plague in focal and potentially focal territories]. Karantin. Zoonoz. Infek. v Kazakhstane. 2001; 3:323–5.

2. Sutyagin V.V., Kislitsyn Yu.V., Lezdin’sh I.A., Kogay O.V., Kim I.B., Berdibekov A.T., Sapozhnikov V.I., Kopbaev E.Sh., Shagaibaeva G.Zh., Nauruzbaev M.O. [Concerning application of polymerase chain reaction for the detection of plague microbe in bone remains of mammals]. Karantin. Zoonoz. Infek. v Kazakhstane. 2014; 2:70–7.

3. Chelomina G.N. [Ancient DNA]. Genetika. 2006; 42(3):293–309.

4. Drancourt M., Aboudharam G., Signoli M., Dutour O., Raoult D. Detection of 400-year-old Yersinia pestis DNA in human dental pulp: an ap- proach to the diagnosis of ancient septicemia. Proc. Natl. Acad. Sci USA. 1998; 95:12637–40.

5. Drancourt M., Signoli M., Dang L.V., Bizot B., Roux V., Tzortzis S., Raoult D. Yersinia pestis Orientalis in remains of ancient plague patients. Emerg. Infect. Dis. 2007; 13(2):332–3.

6. Harbeck M., Seifert L., Hansch S., Wagner D.M., Birdsell D., Parise K.L., Wiechmann I., Grupe G., Thomas A., Keim P., Zoller L., Bramanti B., Riehm J.M., Scholz H.S. Yersinia pestis DNA from skeletal remains from the 6th century AD reveals insights into Justinianic Plague. Plos. Patog. 2013; 9(5):e1003349. DOI: 10.1371/journal.ppat.1003349.

7. Tran N.N., Siginoli M., Fozzati L., Aboudharam G., Raoult D., Drancourt M. High throughput, multiplexed pathogen detection authenticates plague waves in Medieval Venece, Italy. PLoS ONE. 2011. 6(3):e16735. DOI: 10.1371/journal.pone.0016735.