TY - JOUR
T1 - Performance of viral and bacterial genetic markers for sewage pollution tracking in tropical Thailand
AU - Sangkaew, Watsawan
AU - Kongprajug, Akechai
AU - Chyerochana, Natcha
AU - Ahmed, Warish
AU - Rattanakul, Surapong
AU - Denpetkul, Thammanitchpol
AU - Mongkolsuk, Skorn
AU - Sirikanchana, Kwanrawee
N1 - Funding Information:
This work was financially supported by the Chulabhorn Research Institute , Thailand Science Research and Innovation (grant no. SRI6130703 ), and the Kurita Overseas Research Grant (grant no. 19Pth007 to A.K.) provided by Kurita Water and Environment Foundation.
Publisher Copyright:
© 2020
PY - 2021/2/15
Y1 - 2021/2/15
N2 - Identifying sewage contamination via microbial source tracking (MST) marker genes has proven useful for effective water quality management worldwide; however, performance evaluations for these marker genes in tropical areas are limited. Therefore, this research evaluated four human-associated MST marker genes (human polyomaviruses (JC and BK viruses [HPyVs]), bacteriophage crAssphage (CPQ_056), Lachnospiraceae Lachno3, and Bacteroides BacV6-21) for tracking sewage pollution in aquatic environments of Thailand. The viral marker genes, HPyV and crAssphage were highly sensitive and specific to sewage from onsite wastewater treatment plants (OWTPs; n = 19), with no cross-detection in 120 composite swine, cattle, chicken, duck, goat, sheep, and buffalo fecal samples. The bacterial marker genes, Lachno3 and BacV6-21, demonstrated high sensitivity but moderate specificity; however, using both markers could improve specificity to >0.80 (max value of 1.00). The most abundant markers in OWTP samples were Lachno3 and BacV6-21 (5.42–8.02 and nondetect–8.05 log10 copies/100 mL), crAssphage (5.28–7.38 log10 copies/100 mL), and HPyVs (3.66–6.53 log10 copies/100 mL), respectively. Due to their increased specificity, the abundance of viral markers were further investigated in environmental waters, in which HPyVs showed greater levels (up to 4.33 log10 copies/100 mL) and greater detection rates (92.7%) in two coastal beaches (n = 41) than crAssphage (up to 3.51 log10 copies/100 mL and 56.1%). HPyVs were also found at slightly lower levels (up to 5.10 log10 copies/100 mL), but at higher detection rates (92.6%), in a freshwater canal (n = 27) than crAssphage (up to 5.21 log10 copies/100 mL and 88.9%). HPyVs and crAssphage marker genes were identified as highly sensitive and specific for tracking sewage pollution in aquatic environments of Thailand. This study underlines the importance of characterizing and validating MST markers in host groups and environmental waters before including them in a water quality management toolbox.
AB - Identifying sewage contamination via microbial source tracking (MST) marker genes has proven useful for effective water quality management worldwide; however, performance evaluations for these marker genes in tropical areas are limited. Therefore, this research evaluated four human-associated MST marker genes (human polyomaviruses (JC and BK viruses [HPyVs]), bacteriophage crAssphage (CPQ_056), Lachnospiraceae Lachno3, and Bacteroides BacV6-21) for tracking sewage pollution in aquatic environments of Thailand. The viral marker genes, HPyV and crAssphage were highly sensitive and specific to sewage from onsite wastewater treatment plants (OWTPs; n = 19), with no cross-detection in 120 composite swine, cattle, chicken, duck, goat, sheep, and buffalo fecal samples. The bacterial marker genes, Lachno3 and BacV6-21, demonstrated high sensitivity but moderate specificity; however, using both markers could improve specificity to >0.80 (max value of 1.00). The most abundant markers in OWTP samples were Lachno3 and BacV6-21 (5.42–8.02 and nondetect–8.05 log10 copies/100 mL), crAssphage (5.28–7.38 log10 copies/100 mL), and HPyVs (3.66–6.53 log10 copies/100 mL), respectively. Due to their increased specificity, the abundance of viral markers were further investigated in environmental waters, in which HPyVs showed greater levels (up to 4.33 log10 copies/100 mL) and greater detection rates (92.7%) in two coastal beaches (n = 41) than crAssphage (up to 3.51 log10 copies/100 mL and 56.1%). HPyVs were also found at slightly lower levels (up to 5.10 log10 copies/100 mL), but at higher detection rates (92.6%), in a freshwater canal (n = 27) than crAssphage (up to 5.21 log10 copies/100 mL and 88.9%). HPyVs and crAssphage marker genes were identified as highly sensitive and specific for tracking sewage pollution in aquatic environments of Thailand. This study underlines the importance of characterizing and validating MST markers in host groups and environmental waters before including them in a water quality management toolbox.
KW - Fecal pollution
KW - Freshwater
KW - Indicator viruses
KW - Microbial source tracking
KW - Quantitative PCR
KW - Seawater
UR - http://www.scopus.com/inward/record.url?scp=85097634435&partnerID=8YFLogxK
U2 - 10.1016/j.watres.2020.116706
DO - 10.1016/j.watres.2020.116706
M3 - Article
C2 - 33310444
AN - SCOPUS:85097634435
SN - 0043-1354
VL - 190
JO - WATER RESEARCH
JF - WATER RESEARCH
M1 - 116706
ER -
