ABSTRACT
This study aimed to isolate and identify a novel bacterial isolate potential resistant to Mn2+ as well as to investigate the biosorption isotherms of Mn2+ removal from aqueous solutions by the freeze-dried biomass of this bacterium. Sixty three manganese resistant bacterial isolates were recovered from 20 industrial wastewater samples. Interestingly, among them, the isolate number 2120 was able to resist up to 140 ppm of Mn2+ and was selected for the further processes. This isolate was phenotypically characterized and identified by 16S rRNA gene sequencing as Proteus penneri and assigned accession number KY712431 in the GenBank database. The effects of pH and contact time on the biosorption process were studied and optimum pH for biosorption equilibrium was 6 while the optimum contact time was 30 min at room temperature. The maximum adsorption capacity (qmax) of Mn2+ removal from aqueous solutions by the freeze-dried biomass of Proteus penneri 2120 was 175.4 mg/g. According to Freundlich and Langmuir models, the correlation coefficients (R2) were 0.9977 and 0.5525, respectively. Therefore the studied biosorption isotherms are fit well with Freundlich model rather than the Langmuir model. Our findings suggest that the dried biomass of the isolate Proteus penneri 2120 is potentially applicable for manganese metal ion removal from the industrial waste water.
ABSTRACT
Indole negative Proteus species are invariably incorrectly identified as Proteus mirabilis, often missing out isolates of Proteus penneri. We report a case of extended spectrum beta lactamase producing and multidrug-resistant P. penneri isolated from pus from pressure sore of a patient of road traffic accident. Correct and rapid isolation and identification of such resistant pathogen are important as they are significant nosocomial threat.
ABSTRACT
Background & objectives: Indole negative Proteus species are invariably incorrectly identified as P. mirabilis, missing isolates of Proteus penneri. P. penneri is an invasive pathogen capable of causing major infectious diseases still seldom reported in individual cases. We report here the isolation, differentiation, characterization and typing of P. penneri from patients with different clinical infections. Methods: Urine, pus and body fluids collected from patients in intensive care units, wards and out patients departments of a tertiary health care institute from north India were cultured. A total of 61 indole negative Proteus isolates were subjected to extended biochemical tests to differentiate and identify P. penneri from P. mirabilis including failure to produce ornithine decarboxylase (by 0% strains of P. penneri and 100% strains of P. mirabilis) besides P. penneri being uniformly salicin negative, non-utilizer of citrate but ferments sucrose and maltose. Antibiograms and Dienes phenomenon were performed to characterize and type P. penneri isolates besides screening for β-lactamase production. Results: Eight isolates of P. penneri were identified; four from urine, three from abdominal drain-fluid and one from diabetic foot ulcer. P. penneri was isolated as the sole pathogen in all patients having underlying disease; post-operatively. Swarming was not seen in the first strain on primary isolation and was poor in strain-4. All eight isolates were biochemically homologous but multi-drug resistant (MDR) with resistance to 6-8 drugs (up to 12). β-lactamase production was seen in three of five isolates while Dienes phenomenon found four distinct types and discriminated strains differing in resistance even with a single drug. Interpretation & Conclusions: A few additional biochemical tests identified P. penneri isolates; it infected patients with underlying disease and strains were MDR and heterogenous.