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Exploring the rearrangement of sensory intelligence in proteobacteria: insight of Pho regulon
No full textPho regulon is a highly evolved and conserved mechanism across the microbes to fulfil their phosphate need. In this study,
52 proteobacteria genomes were analyzed for the presence of phosphorus acquisition genes, their pattern of arrangement
and copy numbers. The diverse genetic architecture of the Pho regulon genes indicates the evolutionary challenge of nutrient
limitation, particularly phosphorus, faced by bacteria in their environment. The incongruence between the Pho regulon
proteins phylogeny and species phylogeny along with the presence of additional copies of pstS and pstB genes, having cross
similarity with other genera, suggest the possibility of horizontal gene transfer event. The substitution rate analysis and
multiple sequence alignment of the Pho regulon proteins were analyzed to gain additional insight into the evolution of the
Pho regulon system. This comprehensive study confirms that genes perform the regulatory function (phoBR) were vertically
inherited, whereas interestingly, genes whose product involved in direct interaction with the environment (pstS) acquired by
horizontal gene transfer. The substantial amino acid substitutions in PstS most likely contribute to the successful adaptation of
bacteria in different ecological condition dealing with different phosphorus availability. The findings decipher the intelligence
of the bacteria which enable them to carry out the targeted alteration of genes to cope up with the environmental condition
Removal of Chromium and Iron from Real Textile Wastewater by Sorption on Soils
No full textDischarge of textile effluents creates serious environmental problems. This paper investigates the ability of various natural and
modified soils to remove heavy metals present in the textile wastewater. Natural soils such as kaolinite, bentonite, and laterite, along with
modified soils such as organoclay and biopolymer-amended laterite are considered as the potential adsorbents. Iron and chromium present in
the textile wastewater are considered as model pollutants. Batch adsorption studies are carried out to determine the heavy metals sorption
capacity of soils. The heavy metals removal efficiency of soils follows the order bentonite > biopolymer amended laterite soil > laterite soil >
kaolinite > organoclay. Almost complete removal of heavy metals is observed with bentonite and biopolymer-amended laterite. Therefore soil
is determined to be a cost-effective and efficient adsorbent for the removal of heavy metals from textile wastes
Heterogeneous Electro-Fenton Process: Principles and Applications
No full textElectro-Fenton (EF) process has received much attention among the
various advanced oxidation process, due to its higher contaminant removal and
mineralization efficiencies, simplicity in operation, in situ generation of hydrogen
peroxide, etc. Heterogeneous EF process rectifies some of the drawbacks of con-
ventional EF process by using solid catalyst for the generation of reactive hydroxyl
radicals in water medium. The efficiency of various heterogeneous EF catalysts
such as iron oxides, pyrite, iron supported on zeolite, carbon, alginate beads, etc.
was tested by various researchers. All of these catalysts are insoluble in water; and
most of them are stable and reusable in nature. Depending on the iron leaching
characteristics, hydroxyl radicals are generated either in the solution or over the
catalyst surface. Catalysts with higher leaching characteristics exhibit the first
radical generation mechanism, while the stable catalyst with insignificant leaching
exhibits the second radical generation mechanism. Adsorption of the pollutant over
the surface of the catalyst also enhances the pollutant degradation. Overall, hetero-
geneous EF process is very potent, powerful, and useful for the pollutant decon-
tamination from the water medium
Variation in endophytic bacterial communities associated with the rhizomes of tropical Bamboos
No full textgrowing in the central part of India; five Bamboo species were collected and investigated. The culturable endophytic bacteria were isolated by serial dilution and culture-dependant method and their diversity was studied with a 16S rDNA sequence analysis. Consequently, a total of 31 endophytic bacteria isolated from these bamboo species, and the isolates were affiliated to 17 different genera. Proteobacteria was the dominant phylum with the highest diversity containing 11 genera and Staphylococcus, Herbaspirillum, Pseudomonas and Stenotrophomonas being the most frequently observed genera. The Microbacterium, Chryseobacterium, and Chitinophaga were the solitary representative of classes Actinobacteria, Flavobacteria, and Sphingobacteria, respectively. The diversity of bacteria was greater in Dendrocalamus species than in Bambusa species. Based on the putative identity of isolates and their functional roles as reported in the literature, the isolated bacterial endophytes seems to be the promising sustainable bioresource for bioaugmentation of plant growth particularly bamboos in tropical areas including forest
Use of water quality index and multivariate statistical techniques for the assessment of spatial variations in water quality of a small river
No full textRapid urban development has led to a critical
negative impact on water bodies flowing in and around
urban areas. In the present study, 25 physiochemical and
biological parameters have been studied on water samples
collected from the entire section of a small river
originating and ending within an urban area. This study
envisaged to assess the water quality status of river body
and explore probable sources of pollution in the river.
Weighted arithmetic water quality index (WQI) was
employed to evaluate the water quality status of the
river. Multivariate statistical techniques namely cluster
analysis (CA) and principal component analysis (PCA)
were applied to differentiate the sources of variation in
water quality and to determine the cause of pollution in
the river. WQI values indicated high pollution levels in
the studied water body, rendering it unsuitable for any
practical purpose. Cluster analysis results showed that
the river samples can be divided into four groups. Use of
PCA identified four important factors describing the
types of pollution in the river, namely (1) mineral and
nutrient pollution, (2) heavy metal pollution, (3) organic
pollution, and (4) fecal contamination. The deteriorating
water quality of the river was demonstrated to originate
from wide sources of anthropogenic activities, especially
municipal sewage discharge from unplanned housing
areas, wastewater discharge from small industrial units,
livestock activities, and indiscriminate dumping of solid
wastes in the river. Thus, the present study effectively
demonstrates the use of WQI and multivariate statistical
techniques for gaining simpler and meaningful information
about the water quality of a lotic water body as well
as to identify of the pollution sources