Multiple-locus variable-number tandem repeat analysis of Leptospira interrogans and Leptospira borgpetersenii isolated from small feral and wild mammals in East Asia

Abstract

Leptospira spp. are the causative agents of a worldwide zoonosis, leptospirosis, maintained by various mammals. Each Leptospira serovar is frequently associated with a particular maintenance host, and recently, Leptospira genotype-host association has also been suggested to limit serovars to restricted areas. We investigated the molecular characteristics of L. interrogans and L. borgpetersenii which were isolated from small feral and wild animals in four East Asian states using multiple-locus variable-number tandem repeat analysis (MLVA). MLVA using 11 loci was performed on 110 L. interrogans serogroups from Japan (79 strains of 5 serogroups from 3 animal species), Philippines (21; 3; 2), Taiwan (7; 2; 3), and Vietnam (3; 1; 1). A MLVA method using 4 loci for L. borgpetersenii was established and performed on 52 isolates from Japan (26; 3; 7), Philippines (13; 1; 2), and Taiwan (13; 1; 3). In L. interrogans, serogroups Autumnalis and Hebdomadis appeared more genetically diverse than serogroups Bataviae, Grippotyphosa, Icterohaemorrhagiae, Pomona, or Pyrogenes. The former serogroup strains with the exception of one Hebdomadis strain were isolated from Apodemus speciosus while all the latter serogroup strains with the exception of Grippotyphosa were isolated from Rattus norvegicus. L. borgpetersenii was isolated from at least 11 animal species while L. interrogans was isolated from five species, which might suggest a wider host range for L. borgpetersenii. Broad host preference in a single genotype was also observed, which colonized not only different species of the same genera but also multiple animal genera. This study demonstrates that there may be variability in the range of genetic diversity among different Leptospira serogroups, which may be attributed to maintenance host animals and environmental factors.

Molecular epidemiology of pathogenic <i>Leptospira</i> spp. among large ruminants in the Philippines

“…Although the majority of our samples came from water buffalo and the molecular analysis was limited, our findings may further support the previous reports regarding the diversification of Leptospira species [8, 17, 34], wherein this phenomenon can be attributed to maintenance of host animals (alteration of physiology or immune system) or environmental factors [14, 17]. L. borgpetersenii is known to have a broad host range [2, 17] and is restricted to animal-to-animal transmission [5], and therefore is more prone to diversification. A wider study coverage area along with the use of recent molecular typing methods, such as multiple-locus variable-number of tandem repeat analysis and multilocus sequence typing, should be employed in future studies to reveal the genetic diversity of Leptospira present in large ruminants in the Philippines.…”

VNTR analysis demonstrates new patterns and high genetic diversity of Leptospira sp. of animal origin in Brazil

“…; Koizumi et al . ). A particularly interesting and deserves to be highlighted is that the high number of undescribed and unique VNTR patterns, both on L. interrogans / L. kirschneri (5/6, 83·3%) and on L. santarosai strains (17/17, 100%).…”

“…; Koizumi et al . ), highlighting the potential role of infected dogs as sources of infection for other susceptible hosts because they constantly shed leptospires in their urine. Recently, our group demonstrated that barely 20% of asymptomatic dogs may shed leptospires, mainly Icterohaemorrhagiae (Sant'anna et al .…”

“…Although that association with serogroups/serovars still presents some limitations, VNTR has still been widely used to characterize leptospiral strains, mainly those belonging to the serogroup Icterohaemorrhagie (Koizumi et al . ; Harkin and Hays ).…”

Insight into motility-dependent pathogenicity of the zoonotic spirocheteLeptospira

“…Pathogenic serovars of L. interrogans serovar Icterohaemorrhagiae (strain WFA135), an isolate from Rattus norvegicus in Tokyo, Japan, serovar Manilae (strain UP-MMC-NIID) 31,32 and a saprophytic L. biflexa serovar Patoc (strain Patoc I) were used in this study. The serovar of WFA135 was determined by multiple loci variable number of tandem repeats analysis (MLVA) and DNA sequencing of the lic12008 gene 32,33 . Bacteria were cultured in enriched Ellinghausen-McCullough-Johnson-Harris (EMJH) liquid medium (BD Difco, NJ, USA) containing 25 μg/mL spectinomycin at 30 °C for 2 ( L. biflexa ) or 4 ( L. interrogans ) days until the stationary phase.…”