Extremely halotolerant bacteria characteristic of fully cured and dried cod

Gram-positive cocci were isolated in high numbers from salted codfish during processing. They were found to be the main bacterial type in fully cured and dried salted cod. Phenotypic characterization of 37 strains showed them to belong to the novobiocin resistant staphylococci, most likely Staphylococcus arlettae or xylosus. Based on sequencing of 16S rDNA and comparison of 700 bases it was concluded that they should be assigned to the species Staphylococcus arlettae. They were found to be extremely halotolerant, growing well at salt concentrations from 0.06 M NaCl, and even displaying clear growth at 4.5 M NaCl. Likewise, the strains grew over a wide temperature range, from 8 to 45°C. Optimal growth conditions were found to be at 0.4-0.6 M NaCl and 30-32°C. This is all in accordance with findings for related staphylococci that have been isolated from other heavily salted meat or fish products.