K PAHAN

D K GHOSH

S RAY

R GACHHUI

J CHAUDHURI

A MANDAL

University of Calcutta (informally known as Calcutta University or CU) is a collegiate public state university located in Kolkata, West Bengal, India.&nbsp;Within India it is recognized as a &quot;Five-Star University&quot; and accredited &quot;A&quot; Grade by National Assessment and Accreditation Council.

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The University of Calcutta has secured the Fifth position among the Universities of India in the prestigious &quot;Indian University Ranking 2019&quot; list, released by the NIRF of the Ministry of Human Resource Development, Government of India.

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It was established on 24 January 1857, and was one of the first institutions in Asia to be established as a multidisciplinary and Western-style university. Its alumni and faculty include several heads of state, heads of government, social reformers, prominent artists, only academy award winner and Dirac medal winner in India, many Fellows of the Royal Society and five Nobel laureates as of 2019 which is highest in South Asia.

University Of Calcutta

Mercury and organomercurial degrading enzymes in a broad-spectrum Hg-resistant strain of Bacillus pasteurii

Bulletin of Environmental Contamination and Toxicology

Flavobacterium rigense strain PR2, a broad-spectrum mercury-resistant bacterium abundantly present in soil exhibited multiple metal resistance properties. Mercury resistance was due to the sequential action of two mercury-detoxicating enzymes, organomercurial lyase and mercuric reductase. The levels of these enzyme activities were determined using different mercury compounds as inducers and substrates. Mercuric reductase was partially purified from the bacterium and the physicochemical properties of the enzyme were studied. The effect of several enzyme inhibitors and heavy metal ions on the enzyme activity was also studied.

Folia Microbiologica

Studies on Mercury-detoxicating Enzymes from a Broad-Spectrum Mercury-Resistant Strain of Flavobacterium rigense

Five nitrogen-fixing Azotobacter strains isolated from agricultural farms in West Bengal, India, were resistant to mercuric ion and organomercurials. Resistance of Hg-resistant bacteria to mercury compounds is mediated by the activities of mercuric reductase and organomercurial lyase in the presence of NADPH and GSH as cofactors. These bacteria showed an extended lag phase in the presence of 10-50 μmol l-1 HgCl2. Nitrogen-fixing ability of these isolates was slightly inhibited when the mercury-resistant bacterial cells were preincubated with 10 μmol l-1 HgCl2. Acetylene reduction by these bacteria was significantly inhibited (91-97%) by 50 μmol l-1 HgCl2. However, when GSH and NADPH were added to the acetylene reduction assay mixture containing 50 μmol l-1 HgCl2, only 42-50% inhibition of nitrogenase activity was observed. NADPH and GSH might have a role in suppressing the inhibition of N2-fixation in the presence of Hg compounds either by assisting Hg-detoxifying enzymes to lower Hg concentration in the assay mixture or by formation of adduct comprising Hg and GSH which is unable to inhibit nitrogen fixation.

Journal of Applied Bacteriology

Studies on the effect of mercury and organomercurial on the growth and nitrogen fixation by mercury-resistant Azotobacter strains

Biochemistry

Mercuric reductase: homology to glutathione reductase and lipoamide dehydrogenase. Iodoacetamide alkylation and sequence of the active site peptide

Analytical Biochemistry

A rapid micromethod for determination of FMN and FAD in mixtures

Journal	Data powered by TypesetBulletin of Environmental Contamination and Toxicology
Publisher	Data powered by TypesetSpringer-Verlag
ISSN	0007-4861