Full Text Available

Note: Clicking the button above will open the full text document at the original institutional repository in a new window.

Isolation and cahracterization of antibacterial peptides from hemolymph of the soft tick, Ornithodoros savignyi

Dissertation (MSc (Biochemistry))--University of Pretoria, 2002.

Saved in:
Bibliographic Details
Other Authors: Neitz, A.W.H. (Albert Walter Herman)
Format: Thesis
Published: University of Pretoria 2013
Subjects:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1867613498959200256
access_status_str Open Access
author2 Neitz, A.W.H. (Albert Walter Herman)
author_browse Neitz, A.W.H. (Albert Walter Herman)
author_facet Neitz, A.W.H. (Albert Walter Herman)
collection Thesis
dc_rights_str_mv © 2002 University of Pretoria. All rights reserved. The copyright in this work vests in the University of Pretoria. No part of this work may be reproduced or transmitted in any form or by any means, without the prior written permission of the University of Pretoria.
description Dissertation (MSc (Biochemistry))--University of Pretoria, 2002.
format Thesis
id oai:repository.up.ac.za:2263/28499
institution University of Pretoria (South Africa)
last_indexed 2026-06-10T12:37:06.816Z
license_str Other — see source repository
provenance_str_mv Harvested via OAI-PMH from UPSpace — University of Pretoria Institutional Repository
publishDate 2013
publishDateRange 2013
publishDateSort 2013
publisher University of Pretoria
publisherStr University of Pretoria
record_format dspace
source_str UPSpace — University of Pretoria Institutional Repository
spelling oai:repository.up.ac.za:2263/28499 Isolation and cahracterization of antibacterial peptides from hemolymph of the soft tick, Ornithodoros savignyi Neitz, A.W.H. (Albert Walter Herman) Caspar, A.R.M.D. Olivier, Nicholas Abraham Ornithodoros savignyi Ticks research Ticks microbiology Ticks as carriers of disease Argasidae UCTD Dissertation (MSc (Biochemistry))--University of Pretoria, 2002. Invertebrates do not possess an adaptive immune system, but rely on several mechanisms similar to the innate immune system of mammals. The synthesis and release of a host of potent antimicrobial proteins is an important component of this immune response. The antibacterial activity in the hemolymph of Ornithodoros savignyi is specific for Gram-positive bacteria, and the synthesis and release of the antibacterial factors need to be induced by challenging the ticks with heat-killed Gram-negative bacterial suspensions. The induction of the factors is very rapid, leading to a maximal response within one hour following bacterial challenge. The factors are stable at high temperatures, and were found to be protein in nature. By using reverse phase high performance liquid chromatography, four fractions exhibiting antibacterial activity were identified in the hemolymph of immune challenged ticks. Four antibacterial peptides were isolated from these fractions, and the mass analyses of the peptides indicate that there are at least two different antibacterial peptides present in the hemolymph. The N-terminal amino acid sequence of one of the peptides was determined, and the analysis showed that the peptide has high homology with defensin peptides isolated from other tick species. This led to the putative classification of the peptides as part of the invertebrate defensin family. The presence of lysozyme in O. savignyi was studied using molecular biological methods. Vertebrate and invertebrate lysozyme sequences were used to design a lysozyme-specific primer, which was used to amplify specific DNA products from whole tick cDNA using the polymerase chain reaction (PCR). The conditions for the amplification reaction were optimized, the products of the optimized reaction were cloned into a cloning vector and the nucleotide sequences of the products were determined. The nucleotide sequences were used for similarity searches of sequence databases to determine homology with sequences of known proteins. It is deduced the degenerate primer was not specific for lysozyme and did not playa significant role in the amplification of the PCR products. This method is thus not feasible for the investigation of the lysozyme of O. savignyi. Biochemistry unrestricted 2013-09-07T13:37:57Z 2005-10-07 2013-09-07T13:37:57Z 2002-04-01 2002 2005-10-07 Dissertation Olivier, NA 2002, Isolation and characterization of antibacterial peptides from the hemolymph of the soft tick, Ornithodoros savignyi, MSc dissertation, University of Pretoria, Pretoria, viewed yymmdd < http://hdl.handle.net/2263/28499 > H1173/ag http://hdl.handle.net/2263/28499 http://upetd.up.ac.za/thesis/available/etd-10072005-103940/ © 2002 University of Pretoria. All rights reserved. The copyright in this work vests in the University of Pretoria. No part of this work may be reproduced or transmitted in any form or by any means, without the prior written permission of the University of Pretoria. application/pdf University of Pretoria
spellingShingle Ornithodoros savignyi
Ticks research
Ticks microbiology
Ticks as carriers of disease
Argasidae
UCTD
Isolation and cahracterization of antibacterial peptides from hemolymph of the soft tick, Ornithodoros savignyi
title Isolation and cahracterization of antibacterial peptides from hemolymph of the soft tick, Ornithodoros savignyi
title_full Isolation and cahracterization of antibacterial peptides from hemolymph of the soft tick, Ornithodoros savignyi
title_fullStr Isolation and cahracterization of antibacterial peptides from hemolymph of the soft tick, Ornithodoros savignyi
title_full_unstemmed Isolation and cahracterization of antibacterial peptides from hemolymph of the soft tick, Ornithodoros savignyi
title_short Isolation and cahracterization of antibacterial peptides from hemolymph of the soft tick, Ornithodoros savignyi
title_sort isolation and cahracterization of antibacterial peptides from hemolymph of the soft tick ornithodoros savignyi
topic Ornithodoros savignyi
Ticks research
Ticks microbiology
Ticks as carriers of disease
Argasidae
UCTD
url http://hdl.handle.net/2263/28499
http://upetd.up.ac.za/thesis/available/etd-10072005-103940/