(1) The majority of overproduced NIFA and NIFL was insoluble after low-speed centrifugation and was inactive in vitro.
(2) Binding of NifA to the upstream activator sequence (UAS) of the nifH promoter in the presence of the NifL protein was observed under nitrogen-limiting growth conditions.
(3) Complementation analysis of millimicron-induced, amber, frameshift, and deletion mutations indicates there are five polycistronic and two monocistronic operons: nifQ nifB, nifA nifL, nifF, nifM nifV nifS, nifN nifE, nifK nifD nifH, and nifJ.
(4) The nifL protein (a repressor) was coded by an open reading frame of 1,485 bases, corresponding to a protein of 495 amino acids with a calculated molecular weight of 55,242.
(5) Sequences located between -227 and -158 with respect to the nifL transcription start site are required for efficient activation of the nifLA promoter in vitro.
(6) Not all base changes produced similar strong promoter down phenotypes when the nifL and nifH promoters were compared: activation of the nifH promoter by the nifA gene product was less sensitive to base changes in conserved nucleotides than was activation of the equivalently altered nifL promoter by the nifA or ntrC products.
(7) The residual activity is particularly sensitive to inhibition by NifL, suggesting that the role of the N-terminal domain is to block the action of NifL in derepressing conditions.
(8) The activity of NIFA was dramatically reduced in vitro in the presence of the negative regulatory protein NIFL (nifL gene product) but was not inhibited by the presence of a mutant NIFL protein, NIFL2404.
(9) The gene upstream of nifA is therefore designated nifL because of its similarity to the Klebsiella pneumoniae nifL gene in proximity to nifA, in mutant phenotype, and in amino acid sequence of the gene product.
(10) PII is not involved in the nif-specific response to changes in nitrogen status mediated by NifL.
(11) However, the nifL product was not required for the cessation of synthesis of these transcripts at elevated temperatures.
(12) However, the mutant protein retains the ability to increase the occupancy of the -24, -12 region by sigma 54-RNA polymerase, forming closed complexes at the nifL promoter, which are not detectable in the absence of NTRC.
(13) Only two mutants, RK383 and RH383, are active in promoting transcription from either the glnAp2 promoter or the nifL promoter.
(14) Transcription from the sigma 54-dependent Klebsiella pneumoniae nifL and glnAp2 promoters is activated by the general nitrogen regulatory protein NTRC.
(15) These regulatory effects required the nifL product.
(16) The initiation codon (ATG) of nifA overlapped the termination codon(TGA) of nifL, sharing the two bases T and G. A conserved DNA contact point [Gln-(X)3-Ala-(X)3-Gly-(X)5-Val] common in many DNA binding proteins was found in the C-terminal region of the nifA sequence.
(17) The influence of the Klebsiella pneumoniae nifL gene product upon the interaction of the transcriptional activator protein NifA with the nifH promoter has been examined using in vivo dimethylsulphate 'footprinting'.
(18) In NifL- strains, both forms of analysis indicated that the nifL product was involved in nif mRNA destabilization in the presence of O2 and NH4+.
(19) At the wild-type nifL promoter, sigma 54-RNA polymerase makes only limited contacts with the promoter in the absence of NTRC.
(20) Formation of open complexes at glnAp2 peaks at -0.024 and declines at higher superhelical densities, whereas at the wild-type nifL promoter, open complex formation peaks at -0.067 and is not detectable at superhelical densities less than -0.032.
Rifle
Definition:
(v. i.) To commit robbery.
(v. t.) To seize and bear away by force; to snatch away; to carry off.
(v. t.) To strip; to rob; to pillage.
(v. t.) To raffle.
(v. i.) To raffle.
(n.) A gun, the inside of whose barrel is grooved with spiral channels, thus giving the ball a rotary motion and insuring greater accuracy of fire. As a military firearm it has superseded the musket.
(n.) A body of soldiers armed with rifles.
(n.) A strip of wood covered with emery or a similar material, used for sharpening scythes.
(v. t.) To grove; to channel; especially, to groove internally with spiral channels; as, to rifle a gun barrel or a cannon.
(v. t.) To whet with a rifle. See Rifle, n., 3.
Example Sentences:
(1) He's Billy no-mates with a Heckler & Koch sniper-rifle, drowning in loneliness, booze and depression.
(2) A tall young Border Police officer stopped me, his rifle cradled in his arms.
(3) Types of weapons involved included handguns (48%), shotguns (22%), rifles (17%), unspecified weapon (12%), and air rifle (1%).
(4) Snipers fired from rooftops, and plainclothes Saleh supporters armed with automatic rifles, swords and batons attacked the protesters.
(5) Sky News has apologised profusely after one of its presenters was shown rifling through the personal belongings of a stricken passenger at the MH17 crash site.
(6) Deaths due to air rifles are extremely rare; only four other cases were found in the recent English-language literature.
(8) The drug was administered from a distance by means of a projectile syringe shot from a special rifle.
(9) We sampled a sawn-off shotgun and an assault rifle, but cops do get tasers and tear gas to add some urban flavour.
(10) Armed with an assault rifle, he then allegedly headed into two poor villages in Kandahar province, the Taliban's heartland, and went on a murderous rampage in which six people were also injured.
(11) District head Baba Abba Hassan said most victims are children, women and elderly people who could not run fast enough when insurgents drove into Baga, firing rocket-propelled grenades and assault rifles on town residents.
(12) Officers took up positions on rooftops and along railroad tracks and scanned the terrain through rifle scopes and binoculars.
(13) That proposal, similar to a Senate measure backed by the National Rifle Association, would let the attorney general delay a gun purchase by a suspected terrorist for three days, and let law enforcement officials ask a judge to block the purchase altogether.
(14) It can also be seen as a comment on the NSA debate, with Samantha gleefully rifling through Theodore's emails.
(15) Two men in a car tried to drive into the parking lot, jumped out with automatic rifles.
(16) A Royal Military police officer who was attached to the Rifles regiment, Pritchard had been put on duty at an observation post in the Sangin area of Helmand province, where the Taliban had fought hard for control.
(17) And with every heartbeat the blood was pumping up in the air from my thigh.” A man pointed a rifle at his head and threatened to finish him off.
(18) Via al-Aan correspondent Jenan Moussa: Jenan Moussa (@jenanmoussa) I asked a rebel sniper in #Syria : Drop ur rifle for a day & document life through lens of a camera.
(19) Heller called Bundy’s militia supporters, many of whom had trained semi-automatic rifles on government rangers during the stand-off, “patriots”; now his spokesman is saying that the senator “completely disagrees with Mr Bundy’s appalling and racist statements”.
(20) ", but nothing helped, there was so much other noise – both the helicopter above us and the bastard's rifle.