Abstract
A eubacterium producing a blue pigment was isolated from a drinking water filter, and subsequently identified as Vogesella indigofera. This bacterium was further investigated for its morphological and biochemical characteristics after exposure to hexavalent chromium, Cr6+. The threshold Cr6+ concentration inhibiting the pigment production by V. indigofera was 200-300 μg ml-1 in liquid cultures of nutrient broth and 100-150 μg ml-1 on nutrient agar plates. The Cr6+ concentration preventing V. indigofera growth was 300-400 μg ml-1 in liquid cultures, but greater than 150 μg ml-1 on agar plates. Moreover, rugose colonies without the blue pigmentation were observed on agar plates amended with 150 (μg Cr6+) ml-1. The biochemical utilization profiles of the colonies without pigmentation did not differ from the original pigment-producing ones, indicating phenotypic plasticity of this bacterium. The difference of phenotypic expression of V. indigofera under various Cr6+ concentrations might have potential application as a pollution bioindicator for heavy metals.
| Original language | English |
|---|---|
| Pages (from-to) | 475-480 |
| Number of pages | 6 |
| Journal | World Journal of Microbiology and Biotechnology |
| Volume | 17 |
| Issue number | 5 |
| DOIs | |
| State | Published - 2001 |
| Externally published | Yes |
Keywords
- Bioindicator
- Chromium
- Heavy metal
- Phenotypic expression
- Pigment production
- Plasticity
- Rugose colony
- Vogesella indigofera