A modified culture medium for improved isolation of marine vibrios. Issue 9 (18th July 2019)

• Record Type: Journal Article
• Authors: Tagliavia, Marcello; Salamone, Monica; Bennici, Carmelo; Quatrini, Paola; Cuttitta, Angela
• Is Part Of: MicrobiologyOpen. Volume 8:Issue 9(2019)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2019-07-18
• Subjects: marine Vibrio -- modified TCBS -- Vibrio isolation and enumeration -- Vibrio‐specific PCR primers; Microbiology -- Periodicals; 579
• DOI: 10.1002/mbo3.835
• Languages: English
• ISSNs: 2045-8827

Abstract

Abstract: Marine Vibrio members are of great interest for both ecological and biotechnological research, which often relies on their isolation. Whereas many efforts have been made for the detection of food‐borne pathogenic species, much less is known about the performances of standard culture media toward environmental vibrios. We show that the isolation/enumeration of marine vibrios using thiosulfate‐citrate‐bile salts‐sucrose agar (TCBS) as selective medium may be hampered by the variable adaptability of different taxa to the medium, which may result even in isolation failure and/or in substantial total count underestimation. We propose a modified TCBS as isolation medium, adjusted for marine vibrios requirements, which greatly improved their recovery in dilution plate counts, compared with the standard medium. The modified medium offers substantial advantages over TCBS, providing more accurate and likely estimations of the actual presence of vibrios. Modified TCBS allowed the recovery of otherwise undetected vibrios, some of which producing biotechnologically valuable enzymes, thus expanding the isolation power toward potentially new enzyme‐producers Vibrio taxa. Moreover, we report a newly designed Vibrio ‐specific PCR primers pair, targeting a unique rpoD sequence, useful for rapid confirmation of isolates as Vibrio members and subsequent genetic analyses. Abstract : The modification of salt composition of thiosulfate‐citrate‐bile salts‐sucrose agar (TCBS), a commonly used selective medium for Vibrio isolation, greatly improves the plate counts of marine vibrios, which highlights how standard culture media could be in part inappropriate, leading to count underestimation. We identified some—till now unrecognized—vibrios unable to grow onto standard TCBS, and we show a possible mechanism for their isolation failure onto standard medium. Moreover, we propose a Vibrio ‐specific rpoD primers pair, useful to quickly identify environmental isolates as Vibrio members by PCR.