First Description of Natural and Experimental Conjugation between Mycobacteria Mediated by a Linear Plasmid

Background: in a previous study, we detected the presence of a Mycobacterium avium species-specific insertion sequence, IS1245, in Mycobacterium kansasii. Both species were isolated from a mixed M. avium-M. kansasii bone marrow culture from an HIV-positive patient. the transfer mechanism of this insertion sequence to M. kansasii was investigated here.Methodology/Principal Findings: A linear plasmid (pMA100) was identified in all colonies isolated from the M. avium-M. kansasii mixed culture carrying the IS1245 element. the linearity of pMA100 was confirmed. Other analyses suggested that pMA100 contained a covalently bound protein in the terminal regions, a characteristic of invertron linear replicons. Partial sequencing of pMA100 showed that it bears one intact copy of IS1245 inserted in a region rich in transposase-related sequences. These types of sequences have been described in other linear mycobacterial plasmids. Mating experiments were performed to confirm that pMA100 could be transferred in vitro from M. avium to M. kansasii. pMA100 was transferred by in vitro conjugation not only to the M. kansasii strain from the mixed culture, but also to two other unrelated M. kansasii clinical isolates, as well as to Mycobacterium bovis BCG Moreau.Conclusions/Significance: Horizontal gene transfer (HGT) is one of most important mechanisms leading to the evolution and diversity of bacteria. This work provides evidence for the first time on the natural occurrence of HGT between different species of mycobacteria. Gene transfer, mediated by a novel conjugative plasmid, was detected and experimentally reproduced.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Cooperacion Interuniversitaria UAM-Banco Santander con America Latina (CEAL), UAM, SpainConselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Universidade Federal de São Paulo, Dept Microbiol Imunol & Parasitol, Escola Paulista Med, São Paulo, BrazilLab Nacl Comp Cient, Petropolis, BrazilUniv Autonoma Madrid, Fac Med, Dept Prevent Med, Madrid, SpainInst Adolfo Lutz Registro, Nucleo TB & Micobacterioses, São Paulo, BrazilUniversidade Federal de São Paulo, Dept Microbiol Imunol & Parasitol, Escola Paulista Med, São Paulo, BrazilFAPESP: FAPESP - 06/01533-9Web of Scienc

Erratum to: 36th International Symposium on Intensive Care and Emergency Medicine

[This corrects the article DOI: 10.1186/s13054-016-1208-6.]

Production of tifton 85 hay overseeded with white oats or ryegrass

The objective of this experiment was to estimate the curve of dehydration, chemical composition and in vitro dry matter digestibility (IVDMD) and crude protein digestibility (IVCPD) of tifton 85 hay, produced single or overseeded with ryegrass or white oat IPR 126. The experimental design was in randomized blocks, in a 3 × 10 factorial arrangement, with three cropping systems and ten evaluation times (0, 4, 8, 24, 28, 32, 48, 52 and 56 and 71 hours after harvest) during the dehydration process. For chemical composition and in vitro DM and CP digestibility, the experimental design was in randomized blocks with three cropping systems and three evaluation times (before cutting, before baling and 100 days after of storage). It was found that tifton 85 intercropped with white oat kept its higher nutritional value after storage, with 19.78% crude protein and 70.03% of in vitro dry matter digestibility. The participation of white oat in tifton 85 area was 57.04% and for ryegrass, it was 38.52%, but the dry matter yield of single tifton 85 was higher than other intercrops. Thus, it is recommended an oversowing of winter annual species on Tifton 85, without moisture restriction, because of the benefits obtained in the hay nutritional value