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This content will become publicly available on June 1, 2025

Title: Bacterial community and cyanotoxin gene distribution of the Winam Gulf, Lake Victoria, Kenya
Abstract The Winam Gulf (Kenya) is frequently impaired by cyanobacterial harmful algal blooms (cHABs) due to inadequate wastewater treatment and excess agricultural nutrient input. While phytoplankton in Lake Victoria have been characterized using morphological criteria, our aim is to identify potential toxin‐producing cyanobacteria using molecular approaches. The Gulf was sampled over two successive summer seasons, and 16S and 18S ribosomal RNA gene sequencing was performed. Additionally, key genes involved in production of cyanotoxins were examined by quantitative PCR. Bacterial communities were spatially variable, forming distinct clusters in line with regions of the Gulf. Taxa associated with diazotrophy were dominant near Homa Bay. On the eastern side, samples exhibited elevatedcyrAabundances, indicating genetic capability of cylindrospermopsin synthesis. Indeed, near the Nyando River mouth in 2022,cyrAexceeded 10 million copies L−1where there were more than 6000Cylindrospermopsisspp. cells mL−1. In contrast, the southwestern region had elevatedmcyEgene (microcystin synthesis) detections near Homa Bay whereMicrocystisandDolichospermumspp. were observed. These findings show that within a relatively small embayment, composition and toxin synthesis potential of cHABs can vary dramatically. This underscores the need for multifaceted management approaches and frequent cyanotoxin monitoring to reduce human health impacts.  more » « less
Award ID(s):
1953468 1840715 2418066
PAR ID:
10522888
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ;
Corporate Creator(s):
Publisher / Repository:
Wiley
Date Published:
Journal Name:
Environmental Microbiology Reports
Volume:
16
Issue:
3
ISSN:
1758-2229
Page Range / eLocation ID:
1-17
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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