Multilocus sequencing typing of Pseudomonas aeruginosa isolates and analysis of potential pathogenicity of typical genotype strains from occupational oxyhelium saturation divers.
BACKGROUND
Pseudomonas aeruginosa (P. aeruginosa) is a common microbe isolated from divers with ear and skin infections. To obtain the epidemic characters of the occurrence of the P. aeruginosa infection, multilocus sequence typing (MLST) was used to assess the genetic background of different strains isolated from divers involved in saturation diving.


METHODS
A total of 64 P. aeruginosa strains from naval divers were sequenced by multilocus sequence typing using seven housekeeping genes (acsA, aroE, guaA, mutL, nuoD, ppsA and trpE). The results were analyzed based on the P. aeruginosa international MLST database to obtain the allelic profiles and sequence types (STs). MLST data were analyzed by Bionumerics 4.0 (http: // pubmlst.org/mlstanalyse) using LIAN and eBURST. Twenty-eight strains with the typical genotype were selected for further analysis of pathogenic characteristics by Caenorhabditis elegans (C. elegans) fast killing model.


RESULTS
Data from MLST revealed a high STs diversity among the strains. Of the 64 strains, 53 strains were assigned to 19 STs, and the remaining 11 clones could not be assigned. ST274 accounted for 18.5% (12/64), and ST260 accounted for 15.62% (10/64). C. elegans killing assay showed that all the test strains had distinct virulent properties as compared with the negative control group. Clone 503-1 had the highest virulence and clone 54 had the lowest virulence as compared with the positive clinical group.


CONCLUSIONS
The P. aeruginosa strains carried by the occupational diver groups in Chinese regions have characteristically dominant STs, and have a relatively strong virulence as compared with the standard strain and the clinically isolated positive control strain.
Shuang-Hong
SH
Chen
Rui-Yong
RY
Chen
Xiong-Li
XL
Xu
Hai-Ting
HT
Chen
D000328:Adult; D000483:Alleles; D000818:Animals; D015373:Bacterial Typing Techniques; D017173:Caenorhabditis elegans; D017931:DNA Primers / Q000235:genetics; D004242:Diving; D004431:Ear, External / Q000382:microbiology; D005838:Genotype; D006371:Helium; D006801:Humans; D008889:Military Personnel; D058885:Multilocus Sequence Typing; D010100:Oxygen; D011550:Pseudomonas aeruginosa / Q000235:genetics* / Q000302:isolation & purification / Q000472:pathogenicity*; D017192:Skin Diseases, Bacterial / Q000382:microbiology; D013045:Species Specificity; D014774:Virulence / Q000235:genetics; D055815:Young Adult
D017931:DNA Primers; D006371:Helium; C038949:heliox; D010100:Oxygen