Functional characterization of a major compatible solute in Deep Sea halophilic eubacteria of active volcanic Barren Island, Andaman and Nicobar Islands, India

AbstractWe have estimated the length at maturity and length-weight relationships for five fish species inhabiting the deep-sea from the Andaman and Nicobar Islands off the Indian coast between 295–650 m deep in a trawl survey carried out in March–April 2017. Hauls were carried out by a high-speed Demersal Trawl Crustacean Version trawl net and analysis was performed for a total of 832 specimens. Length at first maturity of the five deep-sea fish species ranged from 14.28–105.73 cm while length at 90% maturity was in the range 17.87–159.83 cm. The length at maturity of the fish are Alepocephalus bicolor (male = 66.09, female = 105.73), Bathyclupea hoskynii (m = 15.14, f = 14.15), Chlorophthalmus corniger (m = 17.54, f = 15.31), Neoepinnula orientalis (m = 20.76, f = 16.76), and Neoscopelus microchir (m = 14.28, f = 15.40). The b value in the length-weight relationship ranged from 0.69–2.60, i.e. Alepocephalus bicolor (m = 1.93, f = 1.62), Bathyclupea hoskynii (m = 3.5, f = 1.66), Chlorophthalmus corniger (m = 2.07, f = 1.56), Neoepinnula orientalis (m = 2.86, f = 2.46) and Neoscopelus microchir (m = 0.89, f = 0.49). Based on these results, the b value showed an allometric relationship with length for all species studied, because these species have a similar morphometry, i.e. a flattened back. Since they are primary or secondary consumers at the bottom of consumer food webs, their roles are as predators of small–medium prey and as prey of top predators of food web chains.

Download Full-text

Isolation and Characterization of Salt Tolerant Plant Growth Promoting Rhizobacteria from Plants Grown in Tsunami Affected Regions of Andaman and Nicobar Islands

Geomicrobiology Journal ◽

10.1080/01490451.2015.1128994 ◽

2016 ◽

Vol 33 (10) ◽

pp. 942-947 ◽

Cited By ~ 10

Author(s):

Natarajan Amaresan ◽

Krishna Kumar ◽

K. Madhuri ◽

G. Kannamma Usharani

Keyword(s):

Plant Growth ◽

Plant Growth Promoting Rhizobacteria ◽

Salt Tolerant ◽

Andaman And Nicobar Islands ◽

Isolation And Characterization ◽

Tolerant Plant ◽

Plant Growth Promoting ◽

Nicobar Islands ◽

Growth Promoting

Download Full-text

II.—On the Volcanos of the Bay of Bengal

Geological Magazine ◽

10.1017/s0016756800156572 ◽

1879 ◽

Vol 6 (1) ◽

pp. 16-27 ◽

Cited By ~ 3

Author(s):

V. Ball

Keyword(s):

Bay Of Bengal ◽

Andaman And Nicobar Islands ◽

Good Fortune ◽

Nicobar Islands ◽

Barren Island ◽

Volcanic Islands

During the year 1873, it was my good fortune to be one of a party who, in the course of an exploration of the Andaman and Nicobar Islands, were enabled to spend a few hours on the detached volcanic islands of the Bay of Bengal, which are known respectively as Barren Island and Narkondam. The time at our disposal did not admit of our making as thorough an examination as we should have wished, but there was sufficient opportunity for testing the accuracy of the statements regarding the islands which had been previously published, and also for making a few original observations.

Download Full-text

Two Alternative Pathways for the Synthesis of the Rare Compatible Solute Mannosylglucosylglycerate in Petrotoga mobilis

Journal of Bacteriology ◽

10.1128/jb.01424-09 ◽

2010 ◽

Vol 192 (6) ◽

pp. 1624-1633 ◽

Cited By ~ 16

Author(s):

Chantal Fernandes ◽

Vitor Mendes ◽

Joana Costa ◽

Nuno Empadinhas ◽

Carla Jorge ◽

...

Keyword(s):

Sequence Homology ◽

Thermotoga Maritima ◽

Functional Characterization ◽

Compatible Solute ◽

Homologous Gene ◽

Gene Encoding ◽

Alternative Pathways ◽

Cell Extracts ◽

Genes Encoding

ABSTRACT The compatible solute mannosylglucosylglycerate (MGG), recently identified in Petrotoga miotherma, also accumulates in Petrotoga mobilis in response to hyperosmotic conditions and supraoptimal growth temperatures. Two functionally connected genes encoding a glucosyl-3-phosphoglycerate synthase (GpgS) and an unknown glycosyltransferase (gene Pmob_1143), which we functionally characterized as a mannosylglucosyl-3-phosphoglycerate synthase and designated MggA, were identified in the genome of Ptg. mobilis. This enzyme used the product of GpgS, glucosyl-3-phosphoglycerate (GPG), as well as GDP-mannose to produce mannosylglucosyl-3-phosphoglycerate (MGPG), the phosphorylated precursor of MGG. The MGPG dephosphorylation was determined in cell extracts, and the native enzyme was partially purified and characterized. Surprisingly, a gene encoding a putative glucosylglycerate synthase (Ggs) was also identified in the genome of Ptg. mobilis, and an active Ggs capable of producing glucosylglycerate (GG) from ADP-glucose and d-glycerate was detected in cell extracts and the recombinant enzyme was characterized, as well. Since GG has never been identified in this organism nor was it a substrate for the MggA, we anticipated the existence of a nonphosphorylating pathway for MGG synthesis. We putatively identified the corresponding gene, whose product had some sequence homology with MggA, but it was not possible to recombinantly express a functional enzyme from Ptg. mobilis, which we named mannosylglucosylglycerate synthase (MggS). In turn, a homologous gene from Thermotoga maritima was successfully expressed, and the synthesis of MGG was confirmed from GDP-mannose and GG. Based on the measurements of the relevant enzyme activities in cell extracts and on the functional characterization of the key enzymes, we propose two alternative pathways for the synthesis of the rare compatible solute MGG in Ptg. mobilis.

Download Full-text