Pheno- and genotypic iron acquisition of non-aureus staphylococci: a scoping review of literature with a focus on bovine mastitis.

Staphylococci, a heterogenous group of bacteria, are known for their pathogenic potential in both human and animal hosts. Iron acquisition mechanisms play a pivotal role in their virulence and pathogenesis. While Staphylococcus aureus has been extensively studied in this regard, there is a significant gap in understanding iron uptake systems among non-aureus staphylococci and the closely related mammaliicocci (NASM), particularly those associated with bovine mastitis. This review delves into the diverse strategies employed by staphylococci to scavenge iron from host sources, encompassing extraction from ferritin, heme, transferrin, and lactoferrin. Furthermore, the dearth of knowledge regarding iron acquisition from the host in NASM, with a focus on bovine mastitis, is highlighted. A scoping review of previously published phenotypic and genotypic data highlights key findings on iron uptake in bovine-associated NASM and presents novel genomic findings, in which selected NASM isolates are screened for the first time for xenosiderophore systems, inorganic iron uptake systems, and putative ferritin iron acquisition genes. These results contribute to a more comprehensive understanding of NASM-host interactions. Such insights can pave the way for alternative therapeutic strategies, including leveraging the potential protective effects of specific NASM species or strains against major mastitis pathogens.