The NanI and NanJ Sialidases of Clostridium perfringens Are Not Essential for Virulence

Author:

Chiarezza Martina1,Lyras Dena1,Pidot Sacha J.1,Flores-Díaz Marietta2,Awad Milena M.1,Kennedy Catherine L.1,Cordner Leanne M.1,Phumoonna Tongted1,Poon Rachael1,Hughes Meredith L.1,Emmins John J.3,Alape-Girón Alberto24,Rood Julian I.1

Affiliation:

1. Bacterial Pathogenesis Research Group and ARC Centre of Excellence in Structural and Functional Microbial Genomics, Department of Microbiology, Monash University, Clayton, Victoria 3800, Australia

2. Instituto Clodomiro Picado, Facultad de Microbiologia, Universidad de Costa Rica, San Jose, Costa Rica

3. Department of Immunology, Monash University, Prahan, Victoria 3004, Australia

4. Centro de Investigaciones en Estructuras Microscópicas (CIEMic) and Departamento de Bioquímica, Facultad de Medicina, Universidad de Costa Rica, San José, Costa Rica

Abstract

ABSTRACT The essential toxin in Clostridium perfringens -mediated gas gangrene or clostridial myonecrosis is alpha-toxin, although other toxins and extracellular enzymes may also be involved. In many bacterial pathogens extracellular sialidases are important virulence factors, and it has been suggested that sialidases may play a role in gas gangrene. C. perfringens strains have combinations of three different sialidase genes, two of which, nanI and nanJ , encode secreted sialidases. The nanI and nanJ genes were insertionally inactivated by homologous recombination in derivatives of sequenced strain 13 and were shown to encode two functional secreted sialidases, NanI and NanJ. Analysis of these derivatives showed that NanI was the major sialidase in this organism. Mutation of nanI resulted in loss of most of the secreted sialidase activity, and the residual activity was eliminated by subsequent mutation of the nanJ gene. Only a slight reduction in the total sialidase activity was observed in a nanJ mutant. Cytotoxicity assays using the B16 melanoma cell line showed that supernatants containing NanI or overexpressing NanJ enhanced alpha-toxin-mediated cytotoxicity. Finally, the ability of nanI , nanJ , and nanIJ mutants to cause disease was assessed in a mouse myonecrosis model. No attenuation of virulence was observed for any of these strains, providing evidence that neither the NanI sialidase nor the NanJ sialidase is essential for virulence.

Publisher

American Society for Microbiology

Subject

Infectious Diseases,Immunology,Microbiology,Parasitology

同舟云学术

1.学者识别学者识别

2.学术分析学术分析

3.人才评估人才评估

"同舟云学术"是以全球学者为主线,采集、加工和组织学术论文而形成的新型学术文献查询和分析系统,可以对全球学者进行文献检索和人才价值评估。用户可以通过关注某些学科领域的顶尖人物而持续追踪该领域的学科进展和研究前沿。经过近期的数据扩容,当前同舟云学术共收录了国内外主流学术期刊6万余种,收集的期刊论文及会议论文总量共计约1.5亿篇,并以每天添加12000余篇中外论文的速度递增。我们也可以为用户提供个性化、定制化的学者数据。欢迎来电咨询!咨询电话:010-8811{复制后删除}0370

www.globalauthorid.com

TOP

Copyright © 2019-2024 北京同舟云网络信息技术有限公司
京公网安备11010802033243号  京ICP备18003416号-3