ZIB

Hits per page

hits 1 - 2 | 2 hits

Sorting

Electronic Resource

Detection of Penicillin-binding Proteins in the Endosymbiont of the Trypanosomatid Crithidia deanei (1997)

MOTTA, MARIA CRISTINA M. ; LEAL, LUIS HENRIQUE M. ; SOUZA, WANDERLEY DE ; [et al.]

Oxford, UK : Blackwell Publishing Ltd

The @journal of eukaryotic microbiology 44 (1997), S. 0

add to mindlist on the mindlist

Details

ISSN: 1550-7408

Source: Blackwell Publishing Journal Backfiles 1879-2005

Topics: Biology

Notes: . Growth by serial transfers of the trypanosomatid Crithidia deanei in culture medium containing 1 mg/ml of the β-lactam antibiotics ampicillin or cephalexin resulted in shape distortion of its endosymbiont. The endosymbiont first appeared as filamentous structures with restricted areas of membrane damage. An increase of electron lucid areas was also observed in the endosymbiont matrix. The continuous treatment with β-lactam antibiotics, resulted in endosymbiont membranes fragmentation; and later on the space previously occupied by the symbiont was identified as an electron lucid area in the host cytoplasm. The putative targets of β-lactam antibiotic were two membrane-bound penicillin-binding proteins (PBPs) detected in the Sarkosyl-soluble fraction of purified symbionts labeled with [3H]-benzylpenicillin. The apparent molecular weight of the proteins were 90 kDa (PBP1) and 45 kDa (PBP2). PBP2 represented 85% of the total PBP content in the membrane fraction of the endosymbionts. Competition experiments using the tested antibiotics and [3H]-benzylpenicillin showed that ampicillin and cephalexin have half saturating concentrations considerably higher than [3H]-benzylpenicillin and indicated that PBP1 is the probable lethal target of the antibiotics tested. These results suggest that a physiologically active PBP is present in the cell envelope of C. deanei endosymbionts and may play important roles in the control of processes such as cell division and shape determination.

Type of Medium: Electronic Resource

URL: http://dx.doi.org/10.1111/j.1550-7408.1997.tb05729.x

Permalink

Library	Location	Call Number	Volume/Issue/Year	Availability

Others were also interested in ...

Paper (German National Licenses)

Fulltext

Electronic Resource

Genomic variation in Trypanosoma cruzi clonal cultures (1996)

Alves, A. M. B. ; de Almeida, Darcy F. ; von Krüger, Wanda M. A.

Springer

Parasitology research 82 (1996), S. 410-415

add to mindlist on the mindlist

Details

ISSN: 1432-1955

Source: Springer Online Journal Archives 1860-2000

Topics: Biology , Medicine

Notes: Abstract Spontaneous changes in restriction DNA profiles and pulsed-field gel electrophoresis (PFGE) patterns, along with a concomitant loss of infectivity, were observed in infective clones of Trypanosoma cruzi strain Y either following a number of passages during the exponential growth phase or after subcloning in liver infusion tryptone (LIT) medium using as the probe a genomic fragment of the parasite (pMYP16), indicating naturally occurring rearrangements of DNA sequences. No variation could be detected when the genomic DNA was probed with conserved T. cruzi tubulin and actin genes. There was no correlation between such rearrangements and the life-cycle forms of the parasites, since trypomastigote forms showed the same karyotype and hybridization patterns as did epimastigote forms. The variations observed could be reverted and infectivity, recovered after inoculation of the parasites in newborn mice.