Growth stimulation of Brevibacterium sp. by siderophores

Abstract

Aims: To assess which types of siderophores are typically produced by Brevibacterium and how siderophore production and utilization traits are distributed within this genus. Methods and Results: During co‐cultivation experiments it was found that growth of B. linens Br5 was stimulated by B. linens NIZO B1410 by two orders of magnitude. The stimulation was caused by the production of hydroxamate siderophores by B. linens NIZO B1410 that enabled the siderophore‐auxotrophic strain Br5 to grow faster under the applied iron‐limited growth conditions. Different patterns of siderophore production and utilization were observed within the genus Brevibacterium. These patterns did not reflect the phylogenetic relations within the group as determined by partial 16S rDNA sequencing. Most Brevibacterium strains were found to utilize hydroxamate siderophores. Conclusions: Brevibacteria can produce and utilize siderophores although certain strains within this genus are siderophore‐auxotrophic. Significance and Impact of the Study: It is reported for the first time that brevibacteria produce and utilize siderophores. This knowledge can be utilized to stimulate growth of auxotrophic strains under certain conditions. Enhancing the growth rate of Brevibacterium is of importance for the application of this species, for example, for cheese manufacturing or for industrial production of enzymes or metabolites.

Growth of Aerobic Ripening Bacteria at the Cheese Surface Is Limited by the Availability of Iron

“…It is also possible that iron acquisition is at the origin of major interactions between the microorganisms that grow at the surface of cheese. In fact, siderophores excreted by one strain may be utilized by another strain, whose growth would then be stimulated (26). In contrast, siderophores may also chelate most of the available iron and, as a result, inhibit the growth of strains that are devoid of the corresponding iron-siderophore transport system (39).…”

“…A better understanding of the microbial ecology of the surface of smear-ripened cheeses is needed to improve the control of microorganism growth on the surface of smear-ripened cheeses, which could, for example, facilitate the development of appropriate defined-strain surface cultures (6,8,18). Noordman et al (26) reported that Brevibacterium strains of dairy origin produce and/or utilize siderophores, small, high-affinity iron-chelating compounds (36) that have been detected in several types of cheese (27). In cocultivation experiments, the production of hydroxamate siderophores by a Brevibacterium linens strain strongly stimulated the growth of another Brevibacterium linens strain, which was siderophore auxotrophic (27).…”

Unraveling Microbial Interactions in Food Fermentations: from Classical to Genomics Approaches

“…Micronutrients such as iron have also been reported to be limiting for strains in the biota of smear cheeses. Strains compete for iron pools through the use of specialized molecular systems for harvesting iron, including siderophores (109).…”

Microbial Interactions in Smear-Ripened Cheeses

“…2 ) through the production, release and uptake of iron scavenging molecules e.g. siderophores constitutes a major interspecies competition in various environments (Kosman 2003 ;Chu et al 2010 ;Hibbing et al 2010 ; Bonnefoy and Holmes 2012 ) including cheese (Noordman et al 2006 ;Monnet et al 2010b ;Monnet et al 2012 ). Indeed, cheese contains a very restricted amount of iron due to the low iron concentrations (between 0.2 and 0.4 mg/l) encountered in bovine milk (Gaucheron et al 1997 ;Monnet et al 2012 ).…”