JCM Figure table search 04
Home Help [Feedback] [For Subscribers] [Archive] [Search] [Contents]
This Article
Right arrow Abstract Freely available
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrowReprints and Permissions
Right arrow Copyright Information
Right arrow Books from ASM Press
Right arrow MicrobeWorld
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Wauters, G.
Right arrow Articles by Delmée, M.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Wauters, G.
Right arrow Articles by Delmée, M.

 Previous Article  |  Next Article 

Journal of Clinical Microbiology, December 2004, p. 5923-5924, Vol. 42, No. 12
0095-1137/04/$08.00+0     DOI: 10.1128/JCM.42.12.5923-5924.2004
Copyright © 2004, American Society for Microbiology. All Rights Reserved.

Histidine Decarboxylase in Enterobacteriaceae Revisited

Georges Wauters,* Véronique Avesani, Jacqueline Charlier, Michèle Janssens, and Michel Delmée

University of Louvain, Faculty of Medicine, Microbiology Unit, Brussels, Belgium

Received 18 May 2004/ Returned for modification 12 July 2004/ Accepted 23 August 2004


   ABSTRACT
Top
 Abstract
Text
 References
 
With a modification of Taylor's decarboxylation broth, histidine decarboxylase was detected in Enterobacter aerogenes, Morganella morganii, Raoultella ornithinolytica, and some strains of Citrobacter youngae and Raoultella planticola. This method provides a useful confirmatory test for identification of E. aerogenes strains.


   TEXT
Top
 Abstract
 Text
References
 
In 1961, Møller's decarboxylation broth was used by Havelka for the detection of histidine decarboxylase (HDC), but only 21 strains of Enterobacteriaceae were tested, and their taxonomic position assigned at that time did not allow interpretation of the results reported (5). Later the presence of HDC was investigated by Enjalbert et al. as an additional test to differentiate Enterobacter aerogenes from Klebsiella pneumoniae and other related species (3). These authors examined a large number of strains belonging to the Voges-Proskauer-positive group of Enterobacteriaceae using a method based on histamine extraction from a broth culture and its detection by the addition of a diazonium salt of sulfanilic acid. All E. aerogenes strains were positive, whereas other species were negative.

In this study, we looked at the presence of HDC in 693 strains of Enterobacteriaceae belonging to the different genera and species encountered in clinical specimens. Identification was performed according to Farmer (4). Dubious or atypical strains were confirmed by sequencing of the 16S rRNA gene carried out as described previously (10). The strains are listed in Table 1.


View this table:
[in this window]
[in a new window]
  		TABLE 1. HDC in Enterobacteriaceae

 
A simple method was used, based on the medium described by Taylor for the detection of lysine decarboxylase (9) modified as follows: L-histidine hydrochloride (Sigma-Aldrich, St. Louis, Mo.), 7 g; yeast extract, 3 g; glucose, 1.5 g; bromcresol purple (alcoholic solution, 1%), 2 ml; and distilled water, 1,000 ml. The pH was adjusted to 6.5 ± 0.1. The broth was dispensed in 1.5-ml amounts in 9-mm-diameter tubes and sterilized. After inoculation, the medium was overlaid with paraffin oil. The tubes were incubated at 37°C (25°C for Yersinia sp.), and a deep purple color was observed when histamine was produced by decarboxylation of histidine. Negative reactions turned yellow. The majority of positive results were obtained after 24 h of incubation, but the tests were observed for 2 days.

Our results confirmed those obtained by Enjalbert et al. (3). All E. aerogenes strains were positive. In addition, we found HDC in all Morganella morganii strains tested and also in Raoultella ornithinolytica. Apart from these two species, no other Enterobacteriaceae were positive except for three out of nine strains of Citrobacter youngae and one out of seven strains of Raoultella planticola. These results are reported in Table 1.

To confirm the validity of these results, cloning and sequencing of the HDC gene were performed in 10 study strains, according to Takahashi et al. (8). The HDC gene was detected in two E. aerogenes strains but not in two E. cloacae strains. The three C. youngae strains positive in the HDC test were also positive for the HDC gene, whereas a negative strain of this species did not possess the gene. Similarly, in the positive R. planticola strain, the HDC gene was present, and it was absent in a negative control strain.

HDC can be detected with Møller's decarboxylase broth, as performed by Havelka (5). However, the color shift is not obvious and is often delayed. The medium turns grayish yellow in positive reactions, which are therefore not so clearly defined as in the Taylor modified broth, which usually turns purple within 24 h. Although the method described by Enjalbert et al. (3) is presented as a simple test, the extraction of histamine followed by the use of reagents for its detection is more tedious and time-consuming in the routine laboratory than the use of our HDC broth.

E. aerogenes has become an important nosocomial pathogen in the last few decades (2). Although strains with a typical profile are easy to identify by phenotypic characteristics, some strains, especially those with poor motility and/or delayed ornithine decarboxylase activity, may be misidentified as K. pneumoniae. Commercial systems do not always correctly identify E. aerogenes. In a comparative study of the BBL Crystal E/NE and API 20 E systems, 10 strains of E. aerogenes were examined. Three strains failed to be correctly identified by the BBL Crystal system, and one failed to be correctly identified by the API 20 E (11). In another study on the evaluation of the Microscan Rapid Gram-Negative ID Type 3 panel, 2 strains of E. aerogenes out of 10 were not identified and 1 was identified only by additional tests (7). It has been reported that Enterobacter species are more often misidentified by commercial systems than other Enterobacteriaceae (1). HDC provides a valuable confirmatory test for the identification of E. aerogenes, since no negative results were found in more than 50 clinical isolates. It could be helpful in strains with atypical characteristics, such as poor motility or delayed ornithine decarboxylase activity, or whenever results of identification by commercial systems are dubious or not discriminatory.

Production of histamine from histidine was reported by Kanki et al. in R. ornithinolytica and R. planticola (6), but using our method, decarboxylation was detected in only one out of seven R. planticola strains.

The medium proposed here is simple to prepare, and the test can readily be performed in any routine laboratory.


   FOOTNOTES
 
* Corresponding author. Mailing address: University of Louvain, Microbiology Unit, UCL/5490, Av. Hippocrate 54, B-1200 Brussels, Belgium. Phone: 32 2 7645490. Fax: 32 2 7649440. E-mail: wauters{at}mblg.ucl.ac.be. Back


   REFERENCES
Top
 Abstract
 Text
 References
 

  1. Abbott, S. 2003. Klebsiella, Enterobacter, Citrobacter, Serratia, Plesiomonas, and other Enterobacteriaceae. p. 684-700. In P. R. Murray, E. J. Baron, J. H. Jorgensen, M. A. Pfaller, and R. H Yolken (ed.), Manual of clinical microbiology, 8th ed., vol. 1. ASM Press, Washington, D.C.
  2. De Gheldre, Y., M. J. Struelens, Y. Glupczynski, P. De Mol, N. Maes, C. Nonhoff, H. Chetoui, C. Sion, O. Ronveaux, M. Vaneechoutte, and le Groupement pour le Dépistage, l'Etude et la Prevention des Infections Hospitalières (GDEPIH-GOSPIZ). 2001. National epidemiologic surveys of Enterobacter aerogenes in Belgian hospitals from 1996 to 1998. J. Clin. Microbiol. 39:889-896.[Abstract/Free Full Text]
  3. Enjalbert, F., C. Richard, M. Attisso, and A. Cremieux. 1979. Detection and significance of histidine decarboxylase (HDC) in "Klebsiella", "Enterobacter" and "Serratia." Ann. Microbiol (Paris) 130A:385-388.[Medline]
  4. Farmer, J. I. 2003. Enterobacteriaceae: introduction and identification., p. 636-653. In P. R. Murray, E. J. Baron, J. H. Jorgensen, M. A. Pfaller, and R. H Yolken (ed.), Manual of clinical microbiology, 8th ed., vol. 1. Washington, D.C.
  5. Havelka, B. 1969. Contribution on the use of Møller's medium for the demonstration of histidine decarboxylase. J. Hyg. Epidemiol. Microbiol. Immunol. 13:463-467.[Medline]
  6. Kanki, M., T. Yoda, T. Tsukamoto, and T. Shibata. 2002. Klebsiella pneumoniae produces no histamine: Raoultella planticola and Raoultella ornithinolytica strains are histamine producers. Appl. Environ. Microbiol. 68:3462-3466.[Abstract/Free Full Text]
  7. O'Hara, C. M., and J. M. Miller. 2002. Ability of the MicroScan Rapid Gram-Negative ID Type 3 panel to identify nonenteric glucose-fermenting and nonfermenting gram-negative bacilli. J. Clin. Microbiol. 40:3750-3752.[Abstract/Free Full Text]
  8. Takahashi, H., B. Kimura, M. Yoshikawa, and T. Fujii. 2003. Cloning and sequencing of the histidine decarboxylase genes of gram-negative, histamine-producing bacteria and their application in detection and identification of these organisms in fish. Appl. Environ. Microbiol. 69:2568-2579.[Abstract/Free Full Text]
  9. Taylor, W. I. 1961. Isolation of salmonellae from food samples. V. Determination of the method of choice for enumeration of Salmonella. Appl. Microbiol. 9:487-490.[Medline]
  10. Wauters, G., V. Avesani, K. Laffineur, J. Charlier, M. Janssens, B. Van Bosterhaut, and M. Delmee. 2003. Brevibacterium lutescens sp. nov., from human and environmental samples. Int. J. Syst. Evol. Microbiol. 53:1321-1325.[Abstract/Free Full Text]
  11. Wauters, G., A. Boel, G. P. Voorn, J. Verhaegen, F. Meunier, M. Janssens, and L. Verbist. 1995. Evaluation of a new identification system, Crystal Enteric/Non-Fermenter, for gram-negative bacilli. J. Clin. Microbiol. 33:845-849.[Abstract]

Journal of Clinical Microbiology, December 2004, p. 5923-5924, Vol. 42, No. 12
0095-1137/04/$08.00+0     DOI: 10.1128/JCM.42.12.5923-5924.2004
Copyright © 2004, American Society for Microbiology. All Rights Reserved.



This article has been cited by other articles:


This Article
Right arrow Abstract Freely available
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrowReprints and Permissions
Right arrow Copyright Information
Right arrow Books from ASM Press
Right arrow MicrobeWorld
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Wauters, G.
Right arrow Articles by Delmée, M.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Wauters, G.
Right arrow Articles by Delmée, M.

Home Help [Feedback] [For Subscribers] [Archive] [Search] [Contents]
Antimicrob. Agents Chemother. Clin. Microbiol. Rev.
Clin. Vaccine Immunol. ALL ASM JOURNALS