that accompany As stress in recent findings. As-induced cellular metabolic processes
and the resultant damage is a prerequisite to research. Phytobial remediation to study
As (III or V) mitigation is an innovative tool using plants and microbes to study As
contamination in the environment. Recently, plant growth-promoting bacteria
(PGPB) that assists phytoremediation has been highly exhibited for both promoting
plant metal resistance/tolerance and inducing plant growth by adherence/transformation or degradation from toxic to nontoxic forms of As (Alka et al. 2020). Being
similar to a phosphate structure, Arsenate reportedly enters the bacterial cell mediated by phosphate transport system. Its toxicity is due to its interference in normal
phosphorylation processes by replacing cellular phosphate. In the recent past, entry
of arsenite in the cells through aquaglyceroporins (mammalian) at neutral pH in
bacteria, yeasts, and mammals was well demonstrated. Furthermore, its toxicity
depends on its binding to sulfhydryl clusters of cysteine deposits in proteins, thus
deactivating them (Ji and Silver 1992).
2 Arsenic Concentration in Aquatic Environment
In the present time, the existence of arsenic in groundwater has become a substance
of serious fear due to its adverse health effects. As groundwater contamination
becomes prevalent in many countries around the world, including Argentina,
Bangladesh, Canada, China, Chile, Hungary, India, Japan, Mexico, New Zealand,
Pakistan, Poland, Taiwan, and the United States (Shahid et al. 2015, 2017; Shakoor
et al. 2015, 2016; Naujokas et al. 2013; Bhowmick et al. 2018; Naidu et al. 2006).
Severe arsenicosis cases like cancerous keratosis, black foot disease (BFD), and
hyperpigmentation have been reported in Taiwan. A huge population in Bangladesh,
many areas in Punjab and Sindh provinces in Pakistan, and nearly 59 districts in
West Bengal, India (Chakraborti et al. 2010) are dependent on As-contaminated
groundwater for consumption and irrigation needs (Bhowmick et al. 2018; Shakoor
et al. 2015; Abedin et al. 2002; Farooqi et al. 2007; Shahid et al. 2017). The first
2 arsenic contaminations in India were reported from West Bengal in 1984, and since
then many states in the floodplains of the Himalayan plateau has joined the list.
Above 0.2 million people in West Bengal have been detected with clinical manifestation of As-related toxicity. The geogenic release of As in the groundwater in some
countries is notably more than 3000 μg L
À1 groundwater (Shahid et al. 2015; Niazi
et al. 2017; Shakoor et al. 2015). Recent reports of As contamination in groundwater
from large areas of the north eastern (NE) region of India have highlighted the
propensity of the problem. Water consumption at the NE region is reliant on
naturally occurring spring, dug well, and pond water. Conferring to recommendations of the World Health Organization (WHO), the safety limit of As in potable
water is 10 μg L
À1 , which is being followed throughout the world with exceptions in
some South and Southeast Asian countries (Shahid et al. 2017; Abid et al. 2016; Pio
et al. 2015; Ravenscroft et al. 2009). Remarkably, it has been projected that about
60% of the water resources that are polluted with arsenic levels are considerably
12 Arsenic-Transforming Bacteria: A Potential Weapon for Arsenic-Contaminated Soil
241
and the resultant damage is a prerequisite to research. Phytobial remediation to study
As (III or V) mitigation is an innovative tool using plants and microbes to study As
contamination in the environment. Recently, plant growth-promoting bacteria
(PGPB) that assists phytoremediation has been highly exhibited for both promoting
plant metal resistance/tolerance and inducing plant growth by adherence/transformation or degradation from toxic to nontoxic forms of As (Alka et al. 2020). Being
similar to a phosphate structure, Arsenate reportedly enters the bacterial cell mediated by phosphate transport system. Its toxicity is due to its interference in normal
phosphorylation processes by replacing cellular phosphate. In the recent past, entry
of arsenite in the cells through aquaglyceroporins (mammalian) at neutral pH in
bacteria, yeasts, and mammals was well demonstrated. Furthermore, its toxicity
depends on its binding to sulfhydryl clusters of cysteine deposits in proteins, thus
deactivating them (Ji and Silver 1992).
2 Arsenic Concentration in Aquatic Environment
In the present time, the existence of arsenic in groundwater has become a substance
of serious fear due to its adverse health effects. As groundwater contamination
becomes prevalent in many countries around the world, including Argentina,
Bangladesh, Canada, China, Chile, Hungary, India, Japan, Mexico, New Zealand,
Pakistan, Poland, Taiwan, and the United States (Shahid et al. 2015, 2017; Shakoor
et al. 2015, 2016; Naujokas et al. 2013; Bhowmick et al. 2018; Naidu et al. 2006).
Severe arsenicosis cases like cancerous keratosis, black foot disease (BFD), and
hyperpigmentation have been reported in Taiwan. A huge population in Bangladesh,
many areas in Punjab and Sindh provinces in Pakistan, and nearly 59 districts in
West Bengal, India (Chakraborti et al. 2010) are dependent on As-contaminated
groundwater for consumption and irrigation needs (Bhowmick et al. 2018; Shakoor
et al. 2015; Abedin et al. 2002; Farooqi et al. 2007; Shahid et al. 2017). The first
2 arsenic contaminations in India were reported from West Bengal in 1984, and since
then many states in the floodplains of the Himalayan plateau has joined the list.
Above 0.2 million people in West Bengal have been detected with clinical manifestation of As-related toxicity. The geogenic release of As in the groundwater in some
countries is notably more than 3000 μg L
À1 groundwater (Shahid et al. 2015; Niazi
et al. 2017; Shakoor et al. 2015). Recent reports of As contamination in groundwater
from large areas of the north eastern (NE) region of India have highlighted the
propensity of the problem. Water consumption at the NE region is reliant on
naturally occurring spring, dug well, and pond water. Conferring to recommendations of the World Health Organization (WHO), the safety limit of As in potable
water is 10 μg L
À1 , which is being followed throughout the world with exceptions in
some South and Southeast Asian countries (Shahid et al. 2017; Abid et al. 2016; Pio
et al. 2015; Ravenscroft et al. 2009). Remarkably, it has been projected that about
60% of the water resources that are polluted with arsenic levels are considerably
12 Arsenic-Transforming Bacteria: A Potential Weapon for Arsenic-Contaminated Soil
241