The effect of two ribonucleases on the production of Shiga toxin and stx-bearing bacteriophages in Enterohaemorrhagic Escherichia coli

Enterohaemorrhagic Escherichia coli (EHEC) comprise a group of intestinal pathogens responsible for a range of illnesses, including kidney failure and neurological compromise. EHEC produce critical virulence factors, Shiga toxin (Stx) 1 or 2, and the synthesis of Stx2 is associated with worse disease manifestations. Infected patients only receive supportive treatment because some conventional antibiotics enable toxin production. Shiga toxin 2 genes (stx2) are carried in λ-like bacteriophages (stx2-phages) inserted into the EHEC genome as prophages. Factors that cause DNA damage induce the lytic cycle of stx2-phages, leading to Stx2 production. The phage Q protein is critical for transcription antitermination of stx2 and phage lytic genes. This study reports that deficiency of two endoribonucleases (RNases), E and G, significantly delayed cell lysis and impaired production of both Stx2 and stx2-phages, unlike deficiency of either enzyme alone. Moreover, scarcity of both enzymes reduced the concentrations of Q and stx2 transcripts and slowed cell growth.

Effect of nano nitrogen on yield attributes of sweet corn (Zea mays Saccharata) and economics

A field experiment was conducted at Agronomy Farm, RCSM College of Agriculture, Kolhapur (M.S.), India during Kharif, 2020 in black Vertisol soil using split plot design with four replications. The main plot factors consist of time of application viz., T1: 15 days after sowing (DAS), T2: 30 DAS and T3: 45 DAS and sub plot factors consist of doses of nano nitrogen (N) fertilizers viz., N1: 1.00 litre per ha, N2: 1.25 litre per ha and N3: 1.50 litre per ha making total nine treatment combinations. The results of main plot showed that length of cob (20.56 cm), diameter of cob (19.71 cm), weight of cob per plant (222.29 g), number of grains per cob (402.07), green cob yield per ha (138.32 q), green fodder yield per ha (359.75 q), protein content in grain (9.74%) and crude protein in stover (5.18%) were significantly maximum when foliar spray was done at 15 days after sowing (DAS). The gross monetary return (Rs. 5,93,172.04 ha-1) and net monetary return (Rs. 3,78,016.10 ha-1) were significantly maximum with foliar spray at 15 DAS (T1) over later spraying at 30 DAS (T2) and 45 DAS (T3). While, in sub-plot length of cob (18.55 cm), diameter of cob (16.83 cm), weight of cob per plant (208.65 g), number of grains per cob (371.25), green cob yield per ha (125.96 q), green fodder yield per ha (344.39 q), protein content in grain (9.29%) and crude protein in stover (5.10%) were obtained from treatment N3 (1.5 litre ha-1) which was on par with treatment N2 (1.25 litre ha-1) and significantly superior over N1 (1 litre ha-1). The highest value of the gross monetary return (Rs. 5,80,827.23 ha-1) and net monetary return (Rs. 3,59,534.55 ha-1) were obtained from treatment N3 (1.5 litre ha-1) which was at par with treatment N2 (1.25 litre ha-1) and significantly superior over treatment N1 (1.00 litre ha-1).

Structural basis of Q-dependent antitermination

Lambdoid bacteriophage Q protein mediates the switch from middle to late bacteriophage gene expression by enabling RNA polymerase (RNAP) to read through transcription terminators preceding bacteriophage late genes. Q loads onto RNAP engaged in promoter-proximal pausing at a Q binding element (QBE) and adjacent sigma-dependent pause element (SDPE) to yield a Q-loading complex, and Q subsequently translocates with RNAP as a pausing-deficient, termination-deficient Q-loaded complex. Here, we report high-resolution structures of 4 states on the pathway of antitermination by Q from bacteriophage 21 (Q21): Q21, the Q21-QBE complex, the Q21-loading complex, and the Q21-loaded complex. The results show that Q21 forms a torus, a “nozzle,” that narrows and extends the RNAP RNA-exit channel, extruding topologically linked single-stranded RNA and preventing the formation of pause and terminator hairpins.

Structural basis of Q-dependent antitermination

Lambdoid bacteriophage Q protein mediates the switch from middle to late bacteriophage gene expression by enabling RNA polymerase (RNAP) to read through transcription terminators preceding bacteriophage late genes. Q loads onto RNAP engaged in promoter-proximal pausing at a Q binding element (QBE) and an adjacent sigma-dependent pause element (SDPE) to yield a “Q-loading complex,” and Q subsequently translocates with RNAP as a pausing-deficient, termination-deficient “Q-loaded complex.” Here, we report high-resolution structures of four states on the pathway of antitermination by Q from bacteriophage 21 (Q21): Q21, the Q21-QBE complex, the Q21-loading complex, and the Q21-loaded complex. The results show that Q21 forms a torus--a “nozzle”--that narrows and extends the RNAP RNA-exit channel, extruding single-stranded RNA and preventing formation of pause and terminator hairpins.One Sentence SummaryQ forms a “nozzle” that narrows the RNA polymerase RNA-exit channel and extrudes ssRNA, preventing formation of RNA hairpins.

Routine Yoga Practice Impacts Whole Body Protein Utilization in Healthy Women

Whole body protein utilization (WBPU), which includes flux (Q), protein synthesis (PS), protein breakdown (PB), and whole body protein balance (WBPB), provides insight regarding muscle mass, a criterion for sarcopenia. To characterize yoga’s impact on WBPU, body composition and functional measures in healthy (50–65 years) women. WBPU and functional measures were compared between women who routinely practiced yoga (YOGA; n = 7) and nonactive counterparts (CON; n = 8). Q (0.61 ± 0.06 vs. 0.78 ± 0.07,p = .04), PS (3.07 ± 0.37 vs. 4.17 ± 0.40,p = .03), PB (2.59 ± 0.48 vs. 3.80 ± 0.48,p = .05) were lower, and lean body mass higher (64 ± 1 vs. 58 ± 2%,p ≤ .01) for YOGA vs. CON, respectively. WBPB and functional measures were similar. Routine yoga practice influenced WBPU in healthy older women. Study findings are novel and provide a basis for future investigations evaluating long-term benefits of yoga as an alternative mode of exercise for maintaining muscle mass in support of active aging.