Prevalence of Histidine Decarboxylase Genes of Gram-Positive Bacteria in Surströmming as Revealed by qPCR

• Published in: Indian journal of microbiology Vol. 61; no. 1; pp. 96 - 99
• Main Authors: Belleggia, Luca, Milanović, Vesna, Cardinali, Federica, Garofalo, Cristiana, Clementi, Francesca, Aquilanti, Lucia, Osimani, Andrea
• Format: Journal Article
• Language: English
• Published: New Delhi Springer India 01-03-2021; Springer Nature B.V
• Subjects: Amino acids; Bacteria; Biodegradation; Biomedical and Life Sciences; Copy number; Decarboxylation; Gram-positive bacteria; Histamine; Histidine; Histidine decarboxylase; Life Sciences; Medical Microbiology; Microbiology; Short Communications; Variance analysis; Histamine; Fermented fish; Real time PCR; Herrings; gene; hdcA gene
• ISSN: 0046-8991; 0973-7715
• DOI: 10.1007/s12088-020-00907-1

Histamine is a degradation product of the bacterial decarboxylation of the amino acid histidine; such activity is determined by histidine decarboxylase encoded by a gene cluster, carried by some Gram-positive bacteria, that includes the
hdcA
gene. In this study, the presence of the
hdcA
gene in ready-to-eat
surströmming
samples collected from three producers based in Sweden was directly assessed via qPCR analysis for the very first time. Samples from producer A showed
hdcA
average gene abundance of 6.67 ± 0.13 Log cells/gene copies g
−1
; in samples from producer B the average value attested at 5.56 ± 0.06 Log cells/gene copies g
−1
, whereas for samples of producer C
hdcA
average gene abundance attested at 5.30 ± 0.08 Log cells/gene copies g
−1
. ANOVA showed a significantly higher average
hdcA
gene copy number in samples from producer A, whereas no significant differences were seen between average values of
hdcA
gene copy numbers detected in samples from producer B and C. The
hdcA
gene copies detected in the present study could give an estimation of the load of potential histamine-producing bacteria in
surströmming
.