Dataset Information

Phenotypic and genetic features of a novel clinically isolated rough morphotype Candida auris.

ABSTRACT:

Introduction

Candida auris is a newly emerging pathogenic fungus of global concern and has been defined by the World Health Organization (WHO) as a member of the critical group of the most health-threatening fungi.

Methods

This study reveals and reports for the first time that a rough morphotype C. auris strain causes urinary tract infections in non-intensive care unit (ICU) inpatients. Furthermore, the morphology, the scanning electronmicroscopy (SEM), Whole-genome resequencing and RNA sequencing of C. auris possessing rough morphotype colonies compared to their smooth morphotype counterparts.

Results

The newly identified phenotypic variation of C. auris appears round, convex, dry, and burr-like with a rough texture. SEM shows that rough type C. auris has a rough and uneven colony surface with radial wrinkles and irregular spore arrangement. Cells of the rough morphotype C. auris naturally aggregate into clusters with tight connections in the liquid, and it seems that the cell division is incomplete. A genome-wide analysis of the rough type C. auris confirmed its genetic association with the smooth type of C. auris prevalent in China (Shenyang) two years ago; however, single nucleotide polymorphism (SNP) mutations of five genes (ACE2, IFF6, RER2, UTP20, and CaO19.5847) were identified more recently. RNA-seq revealed IFF2/HYR3, DAL5, PSA31, and SIT1 were notably up-regulated, while multiple cell wall-associated genes (ALS1, MNN1, PUL1, DSE1, SCW11, PGA38, RBE1, FGR41, BGLI, GIT3, CEP3, and SAP2) were consistently down-regulated in rough morphotype C. auris.

Discussion

The rough phenotypic variation of C. auris is likely to be related to the structural and functional changes in cell wall proteins. This novel rough morphotype C. auris will provide a basis for further studies concerning the evolutionary characteristics of C. auris.

SUBMITTER: Tian S

PROVIDER: S-EPMC10282645 | biostudies-literature | 2023

REPOSITORIES: biostudies-literature

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Publications

Phenotypic and genetic features of a novel clinically isolated rough morphotype <i>Candida auris</i>.

Tian Sufei S Bing Jian J Chu Yunzhuo Y Li Hailong H Wang Qihui Q Cheng Shitong S Chen Jingjing J Shang Hong H

Frontiers in microbiology 20230607

<h4>Introduction</h4><i>Candida auris</i> is a newly emerging pathogenic fungus of global concern and has been defined by the World Health Organization (WHO) as a member of the critical group of the most health-threatening fungi.<h4>Methods</h4>This study reveals and reports for the first time that a rough morphotype <i>C. auris</i> strain causes urinary tract infections in non-intensive care unit (ICU) inpatients. Furthermore, the morphology, the scanning electronmicroscopy (SEM), Whole-genome ...[more]

PMID: 37350781

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