Deoxyribonucleic acid hybridization (hydroxyapatite method, 55 and 70°C) was used to characterize 38 serovars from 22 named serogroups of Leptospira interrogans and Leptospira bijlexa, 6 serovars from 4 new unnamed serogroups of Leptospira interrogans, and single serovars of the proposed species Leptospira parva and Leptonema illini. Deoxyribonucleic acid relatedness confirmed the validity of Leptospira parva and Leptonema illini. The well-accepted species Leptospira interrogans and Leptospira bijlexa, as currently defined, were extremely heterogeneous. Relatedness results revealed at least five new species among the parasitic serovars formerly included in Leptospira interrogans and two new species among the saprophytic serovars formerly included in Leptospira bijlexa. Serogrouping did not equate with species identification, as serovars from several different subserogroups belonged to different species. The new species named in this paper are Leptospira, noguchii, Leptospira weilii, Leptospira santarosai, Leptospira borgpetersenii, Leptospira meyeri, Leptospira wolbachii, and Leptospira inadai.Leptospiraceae is a family in the Spirochaetales whose type genus is Leptospira (7, 12, 14). The three Leptospira species are Leptospira interrogans, which contains a large number of serogroups whose strains are parasitic or pathogenic for humans and animals (14); Leptospira bijlexa, which contains a large number of serogroups whose strains are primarily found in fresh surface waters and moist soil and are rarely isolated from humans or animals (14); and Leptospira parva, which was isolated from tap water, is not pathogenic for hamsters, and is biochemically intermediate between L . interrogans and L . bijlexa (13). Leptonema, with the single species Leptonema illini, was proposed as a second genus in the Leptospiraceae (12). Leptonema illini deoxyribonucleic acid (DNA) has a guanine plus cytosine (G+C) content of 51 to 53 mol% (12), compared with 47.4 mol% for Leptospira parva (13), 36 to 39 mol% for Leptospira bijlexa (14), and 35 to 41 mol% for Leptospira interrogans (14). Leptonema possesses cytoplasmic tubules which are absent in Leptospira, and the structure of the basal complex on its flagella resembles that of gram-positive bacteria, whereas this structure in Leptospira resembles that of gram-negative bacteria (12). Leptonema strains were isolated from the urine of a healthy bull, a turtle, and water. They are not pathogenic for animals and are biochemically similar to Leptospira bijexa except for their ability to grow in Trypticase soy broth (1, 12). In addition to pathogenicity, Leptospira interrogans differs from Leptospira bijlexa by its inability to grow in the presence of 8-azaguanine and its inability to grow at 13°C (14-17). Two biogroups within Leptospira interrogans differ in their ability to grow in the presence of 2,6-diaminopurine (14). Leptospira parva does not grow in the presence of either of the above chemicals and does grow at 13°C (13). In general, the phenotypic characteristics that reportedly d...

Meningitis and Special of Bacterial and MycoticDiseases, Bldg 1-2226 Mailstop D11, Centers for Disease Control and Prevention, Atlanta, GA 30333, USA DNA relatedness was determined among 303 strains of Lepfospira and Leptonema. Included in the analysis were reference strains from 228 wellcharacterized and recognized serovars. The study included 268 serovars from 29 named and one or more unnamed serogroups. The strains clustered into 17 DNA hybridization groups, representing 12 previously described species (292 strains) and five new genomospecies (1 1 strains). The largest groups included Lepfuspira inferrogans (91 strains from 82 serovars), Lepfospira sanfarosai (65 strains from 59 serovars), Lepfospira borgpefersenii (49 strains from 43 serovars), Lepfospira kirschneri (29 strains from 26 serovars) and Lepfospira noguchii (20 strains from 20 serovars). The new genomospecies include Lepfospira genomospecies 1 (two strains, serovars pinagchang and sichuan), Lepfospira genomospecies 2 (six strains, serovars lushui, manhao 3, manzhuang, nanding, mengla and yunnan), Lepfospira genomospecies 3 (one strain, serovar holland), Lepfospira genomospecies 4 (one strain, serovar hualin) and Lepfospira genomospecies 5 (one strain, serovar saopaulo). With the exception of BalCum, all serogroups with greater than one serovar studied were genetically heterogeneous. Phenotypic tests, including optimal growth temperature, lipase activity and growth inhibition by copper sulfate or 2,6-diaminopurine, were of little use in differentiating DNA relatedness groups. The name Lepfospira alexanderi sp. nov. is proposed for Lepfospira genomospecies 2 (type strain L 60T = ATCC 7O052OT, serovar manhao 3). Division

The BRCA2 germline missense variant, R3052W, resides in the DNA binding domain and has been previously classified as a pathogenic allele. In this study, we sought to determine how R3052W alters the cellular functions of BRCA2 in the DNA damage response. The BRCA2 R3052W mutated protein exacerbates genome instability, is unable to rescue homology-directed repair, and fails to complement cell survival following exposure to PARP inhibitors and crosslinking drugs. Surprisingly, despite anticipated defects in DNA binding or RAD51-mediated DNA strand exchange, the BRCA2 R3052W protein mislocalizes to the cytoplasm precluding its ability to perform any DNA repair functions. Rather than acting as a simple loss-of-function mutation, R3052W behaves as a dominant negative allele, likely by sequestering RAD51 in the cytoplasm.

A presumptive hemagglutination test for the serological diagnosis of leptospirosis in humans is described. The antigen was prepared from a soluble alcohol extract of an andamana strain sorbed to human O-negative erythrocytes and preserved by pyruvic aldehyde fixation. In this study, the overall sensitivity of the hemagglutination test was 92% in contrast to 69% for the presumptive slide agglutination test. The specificity was 95% for the hemagglutination test in comparison with 83% for the slide test.