Characterization of first hemin-requiring Pseudomonas aeruginosa small-colony variants from the blood of an octogenarian male-patient with double pneumonitis

• Published in: Journal of infection and chemotherapy : official journal of the Japan Society of Chemotherapy Vol. 23; no. 12; pp. 852 - 855
• Main Authors: Nagano, Natsumi, Nakaya, Hideo, Nagata, Megumi, Nishizawa, Toru, Kawahara, Ryuji, Matsumoto, Takehisa, Oana, Kozue, Kawakami, Yoshiyuki
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier Ltd 01.12.2017
• Subjects: Aged, 80 and over; Amino Acid Sequence; Aminolevulinic Acid - chemistry; Base Sequence; Culture Media; Hematology, Oncology and Palliative Medicine; Hemin - genetics; Hemin requiring; Humans; Male; Pneumonia, Bacterial - blood; Protoporphyrins - chemistry; Pseudomonas aeruginosa; Pseudomonas aeruginosa - genetics; Pseudomonas aeruginosa - isolation & purification; Pseudomonas Infections - blood; Pyrrole ring; RNA, Ribosomal, 16S - genetics; Small colony variant (SCV); Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; X-factor dependent; δ-aminolevulinic acid (ALA); small-colony variant; BHI; CF; SCV; TSI; oxidation fermentation; Brain-Heart-Infusion; colony-forming-unit; CFU; ALA; cystic fibrosis; OF; triple-sugar-iron; δ-aminolevulinic acid; δ-aminolevulinic acid (ALA); Hemin requiring; X-factor dependent; Small colony variant (SCV); Pseudomonas aeruginosa; Pyrrole ring
• ISSN: 1341-321X; 1437-7780
• DOI: 10.1016/j.jiac.2017.06.003

Abstract A hemin-requiring Pseudomonas aeruginosa small-colony variant (SCV) was isolated from the blood of an octogenarian male-patient with double pneumonitis. The isolate was capable of growing on both blood and chocolate agars but not on MacConkey agars without blood ingredient. Furthermore, the isolate revealed to grow only around the X-factor impregnated discs when examined using the X and V disc strips. However, not only RapID-NH system but also the VITEK2 system failed to identify the isolate. The isolate was finally identified as P. aeruginosa by the sequence of the 16S rRNA genes and the MALDI-TOF MS analysis. Interestingly, the isolate represented positive reaction for δ-aminolaevulinic acid (ALA)-test despite the requirement of hemin. Detailed analysis indicated that the isolate produced protoporphyrin IX from ALA. Therefore, the reason for the hemin dependence was deduced the dysfunction of hemH -encoded ferrochelatase behaving at the end of biosynthetic pathway of heme. However, the genetic analysis of hemH gene demonstrated no variations of both the DNA and the amino-acid sequences. To the best of our knowledge, this is the first clinical isolation of a hemin-dependent P. aeruginosa SCV from blood. (182 words)