PMID- 17642703
OWN - NLM
STAT- PubMed-not-MEDLINE
DCOM- 20100628
LR  - 20070723
IS  - 0255-0857 (Print)
IS  - 0255-0857 (Linking)
VI  - 22
IP  - 2
DP  - 2004 Apr-Jun
TI  - Iron-regulated proteins (IRPS) of Leptospira biflexa serovar Patoc strain Patoc 
      I.
PG  - 92-6
AB  - BACKGROUND: Iron deficiency has been shown to induce the expression of 
      siderophores and their receptors, the iron-regulated membrane proteins in a 
      number of bacterial systems. In this study, the response of Leptospira biflexa 
      serovar Patoc strain Patoc I to conditions of iron deprivation was assessed and 
      the expression of siderophores and iron-regulated proteins is reported. MATERIALS 
      AND METHODS: Two methods were used for establishing conditions of iron 
      deprivation. One method consisted of addition of the iron chelators 
      ethylenediamine-N, N'-diacetic acid (EDDA) and ethylenediamine 
      di-o-hydroxyphenylacetic acid (EDDHPA) and the second method involved the 
      addition of iron at 0.02 microg Fe/mL. Alternatively, iron sufficient conditions 
      were achieved by omitting the chelators in the former method and adding 4 microg 
      Fe/mL of the medium in the latter protocol. Triton X-114 extraction of the cells 
      was done to isolate the proteins in the outer membrane (detergent phase), 
      periplasmic space (aqueous phase) and the protoplasmic cylinder (cell pellet). 
      The proteins were subjected to SDS-PAGE for analysis. RESULTS: In the presence of 
      the iron-chelators, four iron-regulated proteins (IRPs) of apparent molecular 
      masses of 82, 64, 60 and 33 kDa were expressed. The 82-kDa protein was seen only 
      in the aqueous phase, while the other three proteins were seen in both the 
      aqueous and detergent fractions. These proteins were not identified in organisms 
      grown in the absence of the iron chelators. The 64, 60 and the 33 kDa proteins 
      were also demonstrated in organisms grown in media with 0.02 microg Fe/mL. In 
      addition, a 24 kDa protein was found to be down-regulated at this concentration 
      of iron as compared to the high level of expression in organisms grown with 4 
      microg Fe/mL. The blue CAS agar plates with top agar containing 0.02 microg Fe/mL 
      showed a colour change to orange-red. CONCLUSION: The expression of siderophores 
      and iron-regulated proteins under conditions of iron deprivation was demonstrated 
      in the non-pathogenic L. biflexa serovar Patoc.
FAU - Sritharan, M
AU  - Sritharan M
AD  - Department of Animal Sciences, School of Life Sciences, University of Hyderabad, 
      Hyderabad - 500 046, India.
FAU - Asuthkar, S
AU  - Asuthkar S
LA  - eng
PT  - Journal Article
PL  - United States
TA  - Indian J Med Microbiol
JT  - Indian journal of medical microbiology
JID - 8700903
EDAT- 2007/07/24 09:00
MHDA- 2007/07/24 09:01
CRDT- 2007/07/24 09:00
PHST- 2007/07/24 09:00 [pubmed]
PHST- 2007/07/24 09:01 [medline]
PHST- 2007/07/24 09:00 [entrez]
PST - ppublish
SO  - Indian J Med Microbiol. 2004 Apr-Jun;22(2):92-6.