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Abstract Plague, as an ancient zoonotic disease caused by Yersinia pestis, has brought great disasters. The natural plague focus of Marmota himalayana in the Qinghai-Tibet Plateau is the largest, which has been constantly active and the leading source of human plague in China for decades. Understanding the population genetics of M. himalayana and relating that information to the biogeographic distribution of Yersinia pestis and plague outbreaks are greatly beneficial for the knowledge of plague spillover and arecrucial for pandemic prevention. In the present research, we assessed the population genetics of M. himalayana. We carried out a comparative study of plague outbreaks and the population genetics of M. himalayana on the Qinghai-Tibet Plateau. We found that M. himalayana populations are divided into two main clusters located in the south and north of the Qinghai-Tibet Plateau. Fourteen DFR genomovars of Y. pestis were found and exhibited a significant region-specific distribution. Additionally, the increased genetic diversity of plague hosts is positively associated with human plague outbreaks. This insight gained can improve our understanding of biodiversity for pathogen spillover and provide municipally directed targets for One Health surveillance development, which will be an informative next step toward increased monitoring of M. himalayana dynamics.

Plague, as an ancient zoonotic disease caused by Yersinia pestis, has brought great disasters. The natural plague focus of Marmota himalayana in the Qinghai-Tibet Plateau is the largest, which has been constantly active and the leading source of human plague in China for decades. Understanding the population genetics of M. himalayana and relating that information to the biogeographic distribution of Yersinia pestis and plague outbreaks are greatly beneficial for the knowledge of plague spillover and arecrucial for pandemic prevention. In the present research, we assessed the population genetics of M. himalayana. We carried out a comparative study of plague outbreaks and the population genetics of M. himalayana on the Qinghai-Tibet Plateau. We found that M. himalayana populations are divided into two main clusters located in the south and north of the Qinghai-Tibet Plateau. Fourteen DFR genomovars of Y. pestis were found and exhibited a significant region-specific distribution. Additionally, the increased genetic diversity of plague hosts is positively associated with human plague outbreaks. This insight gained can improve our understanding of biodiversity for pathogen spillover and provide municipally directed targets for One Health surveillance development, which will be an informative next step toward increased monitoring of M. himalayana dynamics. [ABSTRACT FROM AUTHOR]

The Himalayan marmot Marmota himalayana is widely distributed across the Qinghai–Tibetan Plateau and lives in social groups, yet the mating system of this highly social marmot species is unknown. In this study, the genetic mating system of Himalayan marmots was investigated using microsatellite markers to determine which mating strategies individuals employ. Results revealed that both monogamous and polygamous mating relationships occur in our study population, indicating that the genetic mating system of this marmot species is promiscuity. This study presents the first genetic evidence on the mating system for Himalayan marmots, yet indicates that further studies employing both a genetic and behavioral framework are needed to better understand the social structure and reproductive biology of this marmot species. [ABSTRACT FROM AUTHOR]

Introduction: Ticks and fleas, as blood-sucking arthropods, carry and transmit various zoonotic diseases. In the natural plague foci of China, monitoring of Yersinia pestis has been continuously conducted inMarmota himalayana and other host animals, whereas other pathogens carried by vectors are rarely concerned in the Qinghai-Tibet Plateau. Methods: In this study, we investigated the microbiota of ticks and fleas sampling from M. himalayana in the Qinghai-Tibet Plateau, China by metataxonomics combined with metagenomic methods. Results: By metataxonomic approach based on full-length 16S rDNA amplicon sequencing and operational phylogenetic unit (OPU) analyses, we described the microbiota community of ticks and fleas at the species level, annotated 1,250 OPUs in ticks, including 556 known species and 492 potentially new species, accounting for 48.50% and 41.71% of the total reads in ticks, respectively. A total of 689 OPUs were detected in fleas, consisting of 277 known species (40.62% of the total reads in fleas) and 294 potentially new species (56.88%). At the dominant species categories, we detected the Anaplasma phagocytophilum (OPU 421) and potentially pathogenic new species of Wolbachia, Ehrlichia, Rickettsia, and Bartonella. Using shotgun sequencing, we obtained 10 metagenomic assembled genomes (MAGs) from vector samples, including a known species (Providencia heimbachae DFT2), and six new species affliated to four known genera, i.e., Wolbachia, Mumia, Bartonella, and Anaplasma. By the phylogenetic analyses based on full-length 16S rRNA genes and core genes, we identified that ticks harbored pathogenic A. phagocytophilum. Moreover, these potentially pathogenic novel species were more closely related to Ehrlichia muris, Ehrlichia muris subsp. eauclairensis, Bartonella rochalimae, and Rickettsia limoniae, respectively. The OPU 422 Ehrlichia sp1 was most related to Ehrlichia muris and Ehrlichia muris subsp. eauclairensis. The OPU 230 Bartonella sp1 and Bartonella spp. (DTF8 and DTF9) was clustered with Bartonella rochalimae. The OPU 427 Rickettsia sp1 was clustered with Rickettsia limoniae. Discussion: The findings of the study have advanced our understanding of the potential pathogen groups of vectors in marmot (Marmota himalayana) in the Qinghai-Tibet Plateau. [ABSTRACT FROM AUTHOR]

ABSTRACT Yersinia pestis is the etiological agent of plague. Marmota himalayana of the Qinghai-Tibetan plateau is the primary host of flea-borne Y. pestis. This study is the report of isolation of Mu-like bacteriophages of Y. pestis from M. himalayana. The isolation and characterization of four Mu-like phages of Y. pestis were reported, which were named as vB_YpM_3, vB_YpM_5, vB_YpM_6, and vB_YpM_23 according to their morphology. Comparative genome analysis revealed that vB_YpM_3, vB_YpM_5, vB_YpM_6, and vB_YpM_23 are phylogenetically closest to Escherichia coli phages Mu, D108 and Shigella flexneri phage SfMu. The role of LPS core structure of Y. pestis in the phages’ receptor was pinpointed. All the phages exhibit “temperature dependent infection,” which is independent of the growth temperature of the host bacteria and dependent of the temperature of phage infection. The phages lyse the host bacteria at 37°C, but enter the lysogenic cycle and become prophages in the chromosome of the host bacteria at 26°C. IMPORTANCE Mu-like bacteriophages of Y. pestis were isolated from M. himalayana of the Qinghai-Tibetan plateau in China. These bacteriophages have a unique temperature dependent life cycle, follow a lytic cycle at the temperature of warm-blooded mammals (37°С), and enter the lysogenic cycle at the temperature of its flea-vector (26°С). A switch from the lysogenic to the lytic cycle occurred when lysogenic bacteria were incubated from lower temperature to higher temperature (initially incubating at 26°C and shifting to 37°C). It is speculated that the temperature dependent lifestyle of bacteriophages may affect the population dynamics and pathogenicity of Y. pestis.

Abstract Background Human granulocytic anaplasmosis is a tick-borne zoonotic disease caused by Anaplasma phagocytophilum. Coinfections with A. phagocytophilum and other tick-borne pathogens are reported frequently, whereas the relationship between A. phagocytophilum and flea-borne Yersnia pestis is rarely concerned. Results A. phagocytophilum and Yersnia pestis were discovered within a Marmota himalayana found dead in the environment, as determined by 16S ribosomal rRNA sequencing. Comparative genomic analyses of marmot-derived A. phagocytophilum isolate demonstrated its similarities and a geographic isolation from other global strains. The 16S rRNA gene and GroEL amino acid sequence identity rates between marmot-derived A. phagocytophilum (JAHLEX000000000) and reference strain HZ (CP000235.1) are 99.73% (1490/1494) and 99.82% (549/550), respectively. 16S rRNA and groESL gene screenings show that A. phagocytophilum is widely distributed in marmots; the bacterium was more common in marmots found dead (24.59%, 15/61) than in captured marmots (19.21%, 29/151). We found a higher Y. pestis isolation rate in dead marmots harboring A. phagocytophilum than in those without it (2 = 4.047, p

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In April 2021, a plague outbreak was identified within one Marmota himalayana family shortly after emerging from hibernation, during plague surveillance in the M. himalayana plague foci of the Qinghai-Tibet Plateau. A total of five marmots were found dead of Yersinia pestis near the same burrow; one live marmot was positive of Y. pestis fraction 1 (F1) antibody. Comparative genome analysis shows that few single nucleotide polymorphisms were detected among the nine strains, indicating the same origin of the outbreak. The survived marmot shows a high titer of F1 antibody, higher than the mean titer of all marmots during the 2021 monitoring period (W = 391.00, Z = 2.81, p < 0.01). Marmots live with Y. pestis during hibernation when the pathogen is inhibited by hypothermia. But they wake up during or just after hibernation with body temperature rising to 37°C, when Y. pestis goes through optimal growth temperature, increases virulence, and causes death in marmots. A previous report has shown human plague cases caused by excavating marmots during winter; combined, this study shows the high risk of hibernation marmot carrying Y. pestis. This analysis provides new insights into the transmission of the highly virulent Y. pestis in M. himalayana plague foci and drives further effort upon plague control during hibernation. [ABSTRACT FROM AUTHOR]

Few studies have examined the succession of plant communities in the alpine zone. Studying the succession of plant communities is helpful to understand how species diversity is formed and maintained. In this study, we used species inventories, a molecular phylogeny, and trait data to detect patterns of phylogenetic and functional community structure in successional plant communities growing on the mounds of Himalayan marmots (Marmota himalayana) on the southeast edge of the Qinghai-Tibet Plateau. We found that phylogenetic and functional diversities of plant communities on marmot mounds tended to cluster during the early to medium stages of succession, then trended toward overdispersion from medium to late stages. Alpine species in early and late stages of succession were phylogenetically and functionally overdispersed, suggesting that such communities were assembled mainly through species interactions, especially competition. At the medium and late stages of succession, alpine communities growing on marmot mounds were phylogenetically and functionally clustered, implying that the communities were primarily structured by environmental filtering. During the medium and late stages of succession the phylogenetic and functional structures of plant communities on marmot mounds differed significantly from those on neighboring sites. Our results indicate that environmental filtering and species interactions can change plant community composition at different successional stages. Assembly of plant communities on marmot mounds was promoted by a combination of traits that may provide advantages for survival and adaptation during periods of environmental change.

Background: Human granulocytic anaplasmosis is a tick-borne zoonotic disease caused by Anaplasma phagocytophilum. Coinfections with A. phagocytophilum and other tick-borne pathogens are reported frequently, whereas the relationship between A. phagocytophilum and flea-borne Yersnia pestis is rarely concerned. Results: A. phagocytophilum and Yersnia pestis were discovered within a Marmota himalayana found dead in the environment, as determined by 16S ribosomal rRNA sequencing. Comparative genomic analyses of marmot-derived A. phagocytophilum isolate demonstrated its similarities and a geographic isolation from other global strains. The 16S rRNA gene and GroEL amino acid sequence identity rates between marmot-derived A. phagocytophilum (JAHLEX000000000) and reference strain HZ (CP000235.1) are 99.73% (1490/1494) and 99.82% (549/550), respectively. 16S rRNA and groESL gene screenings show that A. phagocytophilum is widely distributed in marmots; the bacterium was more common in marmots found dead (24.59%, 15/61) than in captured marmots (19.21%, 29/151). We found a higher Y. pestis isolation rate in dead marmots harboring A. phagocytophilum than in those without it (2 = 4.047, p < 0.05). Marmot-derived A. phagocytophilum was able to live in L929 cells and BALB/c mice but did not propagate well. Conclusions: In this study, A. phagocytophilum was identified for the first time in Marmota himalayana, a predominant Yersinia pestis host. Our results provide initial evidence for M. himalayana being a reservoir for A. phagocytophilum; moreover, we found with the presence of A. phagocytophilum, marmots may be more vulnerable to plague. Humans are at risk for co-infection with both pathogens by exposure to such marmots. [ABSTRACT FROM AUTHOR]

IntroductionThe Qinghai-Tibet Plateau is considered the most plague-heavy region in China, and skinning and eating marmots (Marmota himalayana) are understood to be the main exposure factors to plague. Yersinia pestis is relatively inactive during marmots' hibernation period. However, this case report shows plague infection risk is not reduced but rather increased during the marmot hibernation period if plague exposure is not brought under control.Case PresentationThe patient was a 45-year-old man who presented with high fever, swelling of axillary lymph nodes, and existing hand wounds on his right side. Y. pestis was isolated from his blood and lymphatic fluid. Hence, the patient was diagnosed with a confirmed case of bubonic plague. Later, his condition progressed to septicemic plague. Plague exposure through wounds and delays in appropriate treatment might have contributed to plague progression.ConclusionThis case report reveals that excavating a hibernating marmot is a significant transmission route of plague. Plague prevention and control measures are priority needs during the marmot hibernation period.

A lytic Yersinia pestis phage vB_YpP-YepMm (also named YepMm for briefly) was first isolated from the bone marrow of a Marmota himalayana who died of natural causes on the Qinghai-Tibet plateau in China. Based on its morphologic (isometric hexagonal head and short non-contractile conical tail) and genomic features, we classified it as belonging to the Podoviridae family. At the MOI of 10, YepMm reached maximum titers; and the one-step growth curve showed that the incubation period of the phage was about 10 min, the rise phase was about 80 min, and the lysis amount of the phage during the lysis period of 80 min was about 187 PFU/cell. The genome of the bacteriophage YepMm had nucleotide-sequence similarity of 99.99% to that of the Y. pestis bacteriophage Yep-phi characterized previously. Analyses of the biological characters showed that YepMm has a short latent period, strong lysis, and a broader lysis spectrum. It could infect Y. pestis, highly pathogenic bioserotype 1B/O:8 Y. enterocolitica, as well as serotype O:1b Y. pseudotuberculosis—the ancestor of Y. pestis. It could be further developed as an important biocontrol agent in pathogenic Yersinia spp. infection.

A lytic Yersinia pestis phage vB_YpP - YepMm (also named YepMm for briefly) was first isolated from the bone marrow of a Marmota himalayana who died of natural causes on the Qinghai-Tibet plateau in China. Based on its morphologic (isometric hexagonal head and short non-contractile conical tail) and genomic features, we classified it as belonging to the Podoviridae family. At the MOI of 10, YepMm reached maximum titers; and the one-step growth curve showed that the incubation period of the phage was about 10 min, the rise phase was about 80 min, and the lysis amount of the phage during the lysis period of 80 min was about 187 PFU/cell. The genome of the bacteriophage YepMm had nucleotide-sequence similarity of 99.99% to that of the Y. pestis bacteriophage Yep-phi characterized previously. Analyses of the biological characters showed that YepMm has a short latent period, strong lysis, and a broader lysis spectrum. It could infect Y. pestis , highly pathogenic bioserotype 1B/O:8 Y. enterocolitica , as well as serotype O:1b Y. pseudotuberculosis —the ancestor of Y. pestis. It could be further developed as an important biocontrol agent in pathogenic Yersinia spp. infection. [ABSTRACT FROM AUTHOR]

The Himalayan marmot (Marmota himalayana) mainly lives on the Qinghai-Tibet Plateau and it adopts multiple strategies to adapt to high-altitude environments. According to the principle of convergent evolution as expressed in genes and traits, the Himalayan marmot might display similar changes to other local species at the molecular level. In this study, we obtained high-quality sequences of the CYTB gene, CYTB protein, ND3 gene, and ND3 protein of representative species (n = 20) from NCBI, and divided them into the marmot group (n = 11), the plateau group (n = 8), and the Himalayan marmot (n = 1). To explore whether plateau species have convergent evolution on the microscale level, we built a phylogenetic tree, calculated genetic distance, and analyzed the conservation and space structure of Himalayan marmot ND3 protein. The marmot group and Himalayan marmots were in the same branch of the phylogenetic tree for the CYTB gene and CYTB protein, and mean genetic distance was 0.106 and 0.055, respectively, which was significantly lower than the plateau group. However, the plateau group and the Himalayan marmot were in the same branch of the phylogenetic tree, and the genetic distance was only 10% of the marmot group for the ND3 protein, except Marmota flaviventris. In addition, some sites of the ND3 amino acid sequence of Himalayan marmots were conserved from the plateau group, but not the marmot group. This could lead to different structures and functional diversifications. These findings indicate that Himalayan marmots have adapted to the plateau environment partly through convergent evolution of the ND3 protein with other plateau animals, however, this protein is not the only strategy to adapt to high altitudes, as there may have other methods to adapt to this environment.

Abstract Background After the earthquake on 14, April 2010 at Yushu in China, a plague epidemic hosted by Himalayan marmot (Marmota himalayana) became a major public health concern during the reconstruction period. A rapid assessment of the distribution of Himalayan marmot in the area was urgent. The aims of this study were to analyze the relationship between environmental factors and the distribution of burrow systems of the marmot and to predict the distribution of marmots. Methods Two types of marmot burrows (hibernation and temporary) in Yushu County were investigated from June to September in 2011. The location of every burrow was recorded with a global positioning system receiver. An ecological niche model was used to determine the relationship between the burrow occurrence data and environmental variables, such as land surface temperature (LST) in winter and summer, normalized difference vegetation index (NDVI) in winter and summer, elevation, and soil type. The predictive accuracies of the models were assessed by the area under the curve of the receiving operator curve. Results The models for hibernation and temporary burrows both performed well. The contribution orders of the variables were LST in winter and soil type, NDVI in winter and elevation for the hibernation burrow model, and LST in summer, NDVI in summer, soil type and elevation in the temporary burrow model. There were non-linear relationships between the probability of burrow presence and LST, NDVI and elevation. LST of 14 and 23 °C, NDVI of 0.22 and 0.60, and 4100 m were inflection points. A substantially higher probability of burrow presence was observed in swamp soil and dark felty soil than in other soil types. The potential area for hibernation burrows was 5696 km2 (37.7 % of Yushu County), and the area for temporary burrows was 7711 km2 (51.0 % of Yushu County). Conclusions The results suggested that marmots preferred warm areas with relatively low altitudes and good vegetation conditions in Yushu County. Based on these results, the present research is useful in understanding the niche selection and distribution pattern of marmots in this region.

The complete mitochondrial genome of Marmota himalayana was determined based on next-generation sequencing. Genome length consisted of 16,442 bp, with a base composition of 32.1% A, 31.4% T, 23.7% C, and 12.8% G. It consists of 13 protein-coding genes, 22 tRNAs, 2 ribosomal RNAs, and a control region. The gene order and organization were similar to most of the other vertebrates. The molecular data here we presented could play a useful role to study the evolutionary relationships and population genetics of H. marmot.

A case of primary pneumonic plague (PPP) caused by Yersinia pestis is reported. This case occurred in the largest plague area in China. The patient died after contact with a dog that had captured an infected marmot. Three of 151 contacts were shown to be positive for antibody against F1 antigen by indirect hemagglutination assay, but none had clinical symptoms. There was no secondary case.

Six Gram-stain-positive, facultative anaerobic, nonmotile and rod-shaped strains, designated zg-Y50 T , zg-Y1362, zg-Y1379 T , zg-Y869, zg-629 T and zg-Y636, were isolated from the intestinal contents of Marmota himalayana in Qinghai Province, PR China. Strains zg-Y50 T , zg-Y1379 T and zg-629 T exhibited the highest 16S rRNA gene sequence similarities of 99.2, 98.9 and 98.8 % to Aeromicrobium choanae 9 H-4 T , Aeromicrobium ginsengisoli JCM 14732 T and Aeromicrobium flavum TYLN1 T , respectively. Phylogenetic and phylogenomic analyses based on the 16S rRNA gene and genomic sequences, respectively, revealed that the six strains formed three distinct clades within the genus Aeromicrobium . The genome sizes of strains zg-Y50 T , zg-Y1379 T and zg-629 T were 3.1-3.7 Mb, with DNA G+C contents of 69.6-70.4 mol%. Average nucleotide identity and digital DNA-DNA hybridization values between each novel strain and available members of the genus Aeromicrobium were all below species thresholds. All novel strains contained MK-9 (H 4 ) as the major menaquinone and diphosphatidylglycerol, phosphatidylglycerol and phosphatidylinositol as the polar lipids. The predominant fatty acid of the six isolates was C 18 : 1  ω 9 c . The cell-wall peptidoglycan contained ʟʟ-diaminopimelic acid as the diagnostic diamino acid. Based on the results from this polyphasic taxonomic study, three novel species in the genus Aeromicrobium are proposed, namely, Aeromicrobium duanguangcaii sp. nov. (zg-Y50 T =GDMCC 1.2981 T =KCTC 49764 T ), Aeromicrobium wangtongii sp. nov. (zg-Y1379 T =GDMCC 1.2982 T =KCTC 49765 T ) and Aeromicrobium senzhongii sp. nov. (zg-629 T =CGMCC 1.17414 T =JCM 33888 T ).

Yersinia pestis is the etiological agent of plague. Marmota himalayana of the Qinghai-Tibetan plateau is the primary host of flea-borne Y. pestis. This study is the report of isolation of Mu-like bacteriophages of Y. pestis from M. himalayana . The isolation and characterization of four Mu-like phages of Y. pestis were reported, which were named as vB&#95;YpM&#95;3, vB&#95;YpM&#95;5, vB&#95;YpM&#95;6, and vB&#95;YpM&#95;23 according to their morphology. Comparative genome analysis revealed that vB&#95;YpM&#95;3, vB&#95;YpM&#95;5, vB&#95;YpM&#95;6, and vB&#95;YpM&#95;23 are phylogenetically closest to Escherichia coli phages Mu, D108 and Shigella flexneri phage SfMu. The role of LPS core structure of Y. pestis in the phages' receptor was pinpointed. All the phages exhibit "temperature dependent infection," which is independent of the growth temperature of the host bacteria and dependent of the temperature of phage infection. The phages lyse the host bacteria at 37°C, but enter the lysogenic cycle and become prophages in the chromosome of the host bacteria at 26°C. IMPORTANCE Mu-like bacteriophages of Y. pestis were isolated from M. himalayana of the Qinghai-Tibetan plateau in China. These bacteriophages have a unique temperature dependent life cycle, follow a lytic cycle at the temperature of warm-blooded mammals (37°С), and enter the lysogenic cycle at the temperature of its flea-vector (26°С). A switch from the lysogenic to the lytic cycle occurred when lysogenic bacteria were incubated from lower temperature to higher temperature (initially incubating at 26°C and shifting to 37°C). It is speculated that the temperature dependent lifestyle of bacteriophages may affect the population dynamics and pathogenicity of Y. pestis., Competing Interests: The authors declare no conflict of interest.

Introduction: Ticks and fleas, as blood-sucking arthropods, carry and transmit various zoonotic diseases. In the natural plague foci of China, monitoring of Yersinia pestis has been continuously conducted in Marmota himalayana and other host animals, whereas other pathogens carried by vectors are rarely concerned in the Qinghai-Tibet Plateau., Methods: In this study, we investigated the microbiota of ticks and fleas sampling from M. himalayana in the Qinghai-Tibet Plateau, China by metataxonomics combined with metagenomic methods., Results: By metataxonomic approach based on full-length 16S rDNA amplicon sequencing and operational phylogenetic unit (OPU) analyses, we described the microbiota community of ticks and fleas at the species level, annotated 1,250 OPUs in ticks, including 556 known species and 492 potentially new species, accounting for 48.50% and 41.71% of the total reads in ticks, respectively. A total of 689 OPUs were detected in fleas, consisting of 277 known species (40.62% of the total reads in fleas) and 294 potentially new species (56.88%). At the dominant species categories, we detected the Anaplasma phagocytophilum (OPU 421) and potentially pathogenic new species of Wolbachia, Ehrlichia, Rickettsia , and Bartonella . Using shotgun sequencing, we obtained 10 metagenomic assembled genomes (MAGs) from vector samples, including a known species ( Providencia heimbachae DFT2), and six new species affliated to four known genera, i.e., Wolbachia, Mumia, Bartonella , and Anaplasma . By the phylogenetic analyses based on full-length 16S rRNA genes and core genes, we identified that ticks harbored pathogenic A. phagocytophilum . Moreover, these potentially pathogenic novel species were more closely related to Ehrlichia muris, Ehrlichia muris subsp. eauclairensis, Bartonella rochalimae , and Rickettsia limoniae , respectively. The OPU 422 Ehrlichia sp1 was most related to Ehrlichia muris and Ehrlichia muris subsp. eauclairensis . The OPU 230 Bartonella sp1 and Bartonella spp. (DTF8 and DTF9) was clustered with Bartonella rochalimae . The OPU 427 Rickettsia sp1 was clustered with Rickettsia limoniae ., Discussion: The findings of the study have advanced our understanding of the potential pathogen groups of vectors in marmot ( Marmota himalayana ) in the Qinghai-Tibet Plateau., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Dong, Li, Yang, Gong, Zhu, Huang, Kong, Zhao, Wang, Lu, Pu and Yang.)

Six facultative anaerobic, Gram-stain-positive, oxidase-negative, rod-shaped bacteria (strains zg-B89 T , zg-B12, zg-Y338 T , zg-Y138, zg-Y908 T and zg-Y766), were isolated from the intestinal contents of Marmota himalayana in Qinghai Province, PR China. The 16S rRNA gene sequence analysis showed that zg-B89 T showed highest similarity to Cellulomonas iranensis NBRC 101100 T (99.5 %), zg-Y338 T to Cellulomonas cellasea DSM 20118 T (98.7 %), and zg-Y908 T to Cellulomonas flavigena DSM 20109 T (99.0 %). Phylogenetic and phylogenomic analysis based on 16S rRNA gene and 881 core genes revealed that these six strains formed three separate clades in the genus Cellulomonas . Average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values between these three novel species and all members of the genus Cellulomonas were below species thresholds (95-96 % for ANI and 70 % for dDDH). The DNA G+C contents of zg-B89 T , zg-Y338 T and zg-Y908 T were 73.6, 72.9 and 74.5 %, respectively. Strains zg-B89 T and zg-Y908 T had anteiso-C 15 : 0 , C 16 : 0 and anteiso-C 15 : 1 A, and zg-Y338 T had anteiso-C 15 : 0 , C 16 : 0 and iso-C 16 : 0 as the main fatty acids. All novel type strains had MK-9 (H 4 ) as the predominant respiratory quinone, diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol and phosphatidylinositol mannoside as the major polar lipids, and rhamnose, ribose and glucose as the cell-wall sugars. The peptidoglycan amino acids of zg-B89 T , zg-Y338 T and zg-Y908 T contained ornithine, alanine, glutamic acid and aspartic acid (except for zg-Y338 T ). Based on genotypic, phenotypic, phylogenetic and biochemical properties, the six uncharacterized strains represent three novel species in the genus Cellulomonas , for which the names Cellulomonas xiejunii sp. nov. (type strain zg-B89 T =GDMCC 1.2821 T =KCTC 49756 T ), Cellulomonas chengniuliangii sp. nov. (type strain zg-Y338 T =GDMCC 1.2829 T =KCTC 49754 T ) and Cellulomonas wangsupingiae sp. nov. (type strain zg-Y908 T =GDMCC 1.2820 T =KCTC 49755 T ) are proposed, respectively.

• The first report of isolation of P2-like phages of Y. pestis from M. himalayana. • The LPS core structure of Y. pestis is the phages' receptor. • One of the P2-like phages is a temperature sensitive phage, which could only infect Y. pestis at the temperature of mammalian host (37 °C) but not at the temperature of the flea vector (26 °C). Yersinia pestis is the cause of plague, historically known as the "Black Death". Marmota himalayana in the Qinghai-Tibet Plateau (QTP) natural plague focus is the primary host in China. Although several phages originating from Y. pestis have been characterized. This is the first report of isolation of P2-like phages of Y. pestis from M. himalayana. In this study, the isolation and characterization of three P2-like phages of Y. pestis were reported, which were named as vB_YpM_22, vB_YpM_46 and vB_YpM_50. Comparative genome analysis revealed that vB_YpM_22, vB_YpM_46 and vB_YpM_50 are members of the nonlambdoid P2 family, and are highly similar and collinear with enterobacteriophage P2, plague diagnostic phage L-413C and enterobacteriophage fiAA91-ss. The role of LPS core structure of Y. pestis in the phages' receptor was pinpointed. The findings of this study contribute an advance in our current knowledge of Y. pestis phages and will also play a key role in understanding the evolution of Y. pestis phages. [ABSTRACT FROM AUTHOR]

In high-altitude rangeland environments in Nepal and other Himalayan countries, grazing by domestic livestock poses a threat to local wildlife, in terms of competition for resources and other deleterious changes in behaviour. An experimental approach (before-during-after design) was used to investigate the effects of disturbance by livestock and attending herder on the behaviour of the Himalayan marmot ( Marmota himalayana)-a common burrowing animal. When disturbed by livestock and herder, marmots reduced their foraging activities and conversely increased vigilance levels. After livestock and herder had departed from a marmot colony, the marmots mostly returned to their normal behaviour; however, prolonged vigilance activity was observed. Marmots appear to have habituated to livestock and herder to some extent, but still responding to the livestock and herder by modifying their behaviour. Increased vigilance behaviour at the expense of foraging time may have potential consequences in terms of meeting energy budgets for winter hibernation. Therefore, future increases in livestock numbers could have a deleterious effect on marmots and other ground-dwelling wildlife in the region. [ABSTRACT FROM AUTHOR]

Pastoralism is pervasive and has a long history across the rangelands of Trans-Himalaya. Disturbance associated with pastoralism can influence the behaviour of wild animals; hence, it is important to better understand its effects on wild animal behaviour. We compared the activity budget of the Himalayan marmot ( Marmota himalayana) between areas experiencing both high and low levels of pastoralism, in the Upper Mustang region in Nepal. Scan sampling was used to collect diurnal activity budget data on adult marmots, whereas 2 min focal observations were made on foraging marmots to assess vigilance during foraging. Contrary to our prediction, there was no significant difference between areas of high and low pastoralism in terms of foraging behaviour. However, the vigilance activity of marmots was significantly influenced by the extent of disturbances associated with pastoralism. Marmots scanned the surroundings more often while foraging and spent more time scanning in high pastoralism sites as compared to marmots in low pastoralism sites. Although we found no direct negative effects of pastoralism on foraging time, marmots shifted the time of day when they foraged. This study suggests that marmots adjust their vigilance behaviour according to the environmental conditions in which they occur. These findings have important implications for the conservation of marmots in the wake of increasing pastoral activities and consequent increases in human-wildlife conflict in Nepal. [ABSTRACT FROM AUTHOR]

Summary A case of primary pneumonic plague (PPP) caused by Yersinia pestis is reported. This case occurred in the largest plague area in China. The patient died after contact with a dog that had captured an infected marmot. Three of 151 contacts were shown to be positive for antibody against F1 antigen by indirect hemagglutination assay, but none had clinical symptoms. There was no secondary case. [ABSTRACT FROM AUTHOR]

Four Gram-stain-positive, facultatively anaerobic, non-motile, non-spore-forming and rod-shaped bacteria (lx-72 T , lx-45, ZJ784 T and ZJ955) were isolated from the respiratory tract or faeces of marmot ( Marmota himalayana ) from the Qinghai-Tibet Plateau in China. Analysis of the 16S rRNA gene sequences showed that all strains belong to the genus Canibacter and are more related to Canibacter oris CCUG 64069 T (95.1-97.4 % similarity) than to the genus Leucobacter . Both strain pairs grew well at pH 6-9 and 15-42°C, and ZJ784 T /ZJ955 could tolerate slightly higher NaCl (0.5-4.5 %, w/v) than lx-72 T /lx-45(0.5-3.5 %). Based on whole-genome sequences, the average nucleotide identity and digital DNA-DNA hybridization values between our four isolates and their closest relative were below the species delineation thresholds of 70 % and 95-96 %. The common major fatty acids (>10 %) of our four strains were anteiso-C 15 : 0 and anteiso-C 17 : 0 . For both new type strains, MK-8(H 4 ) and MK-9(H 4 ) were the major isoprenoid quinones, and diphosphatidylglycerol and phosphatidylglycerol were the main polar lipids. The genomic DNA G+C content of all strains was 53.9 mol%. Based on results from the genomic comparison, phylogenetic analysis, and physiological and biochemical characteristics, the four isolates represent two novel species in the genus Canibacter , for which the names Canibacter zhuwentaonis sp. nov. (type strain lx-72 T =KCTC 49658 T =GDMCC 1.2569 T ) and Canibacter zhoujuaniae sp. nov. (type strain ZJ784 T =KCTC 49507 T =GDMCC 1.1997 T ) are proposed.

Highlights: [•] Learning from HIV PEP, we attempted to analyze the efficiency of NAs in HBV PEP. [•] ETV alone or combined with vaccine were analyzed using the Chinese woodchuck model. [•] NA-based strategies prevented hepadnavirus viremia and induced protective immunity. [•] NA-based strategies may be an alternative for HBV PEP. [•] Further clinical trials are warrant for confirming NA-based HBV PEP strategies. [ABSTRACT FROM AUTHOR]

The Himalayan marmot Marmota himalayana is widely distributed across the Qinghai-Tibetan Plateau and lives in social groups, yet the mating system of this highly social marmot species is unknown. In this study, the genetic mating system of Himalayan marmots was investigated using microsatellite markers to determine which mating strategies individuals employ. Results revealed that both monogamous and polygamous mating relationships occur in our study population, indicating that the genetic mating system of this marmot species is promiscuity. This study presents the first genetic evidence on the mating system for Himalayan marmots, yet indicates that further studies employing both a genetic and behavioral framework are needed to better understand the social structure and reproductive biology of this marmot species., Competing Interests: The authors declare that they have no competing interests., (© The Author(s) 2022. Published by Oxford University Press on behalf of Editorial Office, Current Zoology.)

Highlights: [•] The complete coding sequence of the woodchuck CD4 molecule was obtained and analyzed. [•] Two pAbs and four mAbs against wCD4 were produced and identified. [•] Anti-wCD4 mAb G2 effectively suppressed or depleted CD4 T cells in vitro and vivo. [•] This provides a basis for immune-related studies of HBV infection in woodchucks. [ABSTRACT FROM AUTHOR]

Abstract: Type I interferons (IFN-α/β) serve as the first line of defense against viral infection and share the same type I IFN receptor (IFNAR) complex, which is composed of IFNAR1 and -2. The Eastern woodchuck (Marmota monax) and Chinese woodchuck (Marmota himalayana) are suitable for studying hepatitis B virus (HBV) infection. Here, the complete or partial sequences of the IFNARs of both species were obtained and analyzed. Small interference RNAs targeting wIFNAR1 and -2 specifically down-regulated the expression of wIFNAR1 and -2 and the IFN-stimulated gene MxA in a woodchuck cell line, respectively. IFNAR2 was significantly up-regulated in primary woodchuck hepatocytes stimulated with IFN-α or -γ. The expression of woodchuck IFNAR1 and -2 was decreased in woodchucks chronically infected with woodchuck hepatitis virus (WHV). These results are essential for studying type I IFN-related innate immunity and therapy in hepadnaviral infection in the woodchuck model. [Copyright &y& Elsevier]

Abstract: The interferon-α (IFN-α) gene family is an important part of the immune system. Recombinant interferon-α is widely used to treat viral hepatitis and malignant diseases. Marmota himalayana has been found to be susceptible to woodchuck hepatitis virus, a virus genetically related to hepatitis B virus (HBV), and is suitable as an animal model for studies on HBV infection. Here, the IFN-α gene family of M. himalayana (cwIFN-α) was characterized. Sequence data indicate that the cwIFN-α family consists of at least 8 functional sequences and 6 pseudogenes with high homology within the family and to IFN-α of Marmota monax, a related species and well-established animal model. The recombinant cwIFN-α subtypes were expressed and tested to be active in viral protection assay and to induce expression of MxA in a species-specific manner. This work provides essential information for future work on testing new therapeutic approaches of HBV infection based on IFN-α in M. himalayana. [Copyright &y& Elsevier]