Diversity of Microorganisms found in Coastal Waters of Sao Vincente (Cabo Verde), with Assessment of Potentially Pathogenic Bacteria

Abstract

In the oceanic waters of Cabo Verde, prevailing microorganisms are adapted to open ocean conditions, thriving in environments with limited nutrients, while being influenced by factors like salinity, ocean currents, inputs from the land, climatic conditions, etc. In any case, microorganisms play a crucial role by fulfilling a variety of ecological purposes. These environments can function as reservoirs for diverse microorganisms, encompassing both beneficial and potentially harmful types, including pathogens. This study used molecular biology tools to extract the genetic material from surface seawater samples collected in different periods and areas of São Vicente Island. Quantification and amplification of the V4 and V5 region were then performed using universal Forward and Reverse primers (515F-926R) for sequencing to determine the composition of the general bacterial community and possible pathogens associated with human health. The results showed that proteobacteria, cyanobacteria and bacteroidetes dominated the samples, which is in agreement with the findings of other authors, as they are quite predominant in surface waters of the Atlantic Ocean and oligotrophic environments. Presence of archaea was noted, but in a non-significant amount compared to bacteria. Potentially pathogenic bacteria were mostly identified in areas with favorable conditions and intense anthropogenic activity, such as the fish market and the area close to OSCM. Furthermore, most potentially pathogenic bacteria were detected during the dry and cold season compared to the transitional period for rainy seasons, which however is not intense on the island. Recognition of crucial microbial markers linked to changes in water quality can provide information for building early warning systems. This allows authorities to respond promptly, mitigating possible sources of pollution and contamination, reducing health risks and ensuring the safety of marine areas. Ultimately, this safeguards the health and well-being of communities and ecosystems.