Constitutive mutations were sought and found in the N-terminal arm of the Escherichia coli regulatory protein of the arabinose operon, AraC protein. A new mutation, N16D, was of particular interest. Asn-16 is not seen in the crystal structure of the AraC dimerization domain determined in the absence of arabinose, because the N-terminal arm 18 residues are disordered, but in the presence of arab...

The expression of P-glycoprotein (Pgp) is often increased in acute myeloid leukemia (AML). However, little is known of the regulation of Pgp expression by cytotoxics in AML. We examined whether Pgp expression and function in leukemic blasts was altered after a short exposure to cytotoxics. Blasts were isolated from 19 patients with AML (15 patients) or chronic myeloid leukemia in blastic transf...

Besides multiple functions in cellular immunity, interleukin 2 (IL2) causes tumour regression.1-5 Proleukine® [aldesleukin, human recombinant IL2 (rhIL2)] was approved for renal cancer and melanoma. Response rates were low clinical application limited by rapid clearance serious dose-limiting toxicities (DLT), e.g. vascular leakage.6 Thus, reducing systemic toxicity targeting to tumour-associate...

The in vivo transcription start site of the araC message was determined by S1 nuclease mapping of hybrids formed between labeled DNA, and RNA extracted from cells grown under a variety of physiological conditions, including the interval of transient derepression following arabinose addition. Under all conditions tested, transcription initiated from the same nucleotide position at -148.

Substitutions within the interdomain linkers of the AraC/XylS family proteins RhaS and RhaR were tested to determine whether side chain identity or linker structure was required for function. Neither was found crucial, suggesting that the linkers do not play a direct role in activation, but rather simply connect the two domains.

The N-terminal domain of the RNA polymerase alpha subunit (alpha-NTD) was tested for a role in transcription activation by a variety of AraC/XylS family members. Based on substitutions at residues 162 to 165 and an extensive genetic screen we conclude that alpha-NTD is not an activation target for these activators.

A new Salmonella enterica serovar Typhimurium strain has been constructed to facilitate tightly regulated gene expression. Arabinose-inducible and glucose-repressible expression of a T7 RNA polymerase gene that has been integrated with an adjacent araC-P(BAD) control element into the bacterial chromosome allows dynamic control of T7 promoter-driven RNA transcription.

Mesafeli sözle?melere ili?kin TKHK m. 48 hükmü, 7392 say?l? Kanunun 7. maddesiyle, yay?m? tarihinden alt? ay sonra (1/10/2022) yürürlü?e girmek üzere de?i?tirilmi?tir. Yeni düzenlemede “arac?l?k edenler” ifadesi yerine “arac? hizmet sa?lay?c?lar” terimi kullan?lm?? ve arac? sa?lay?c?lar?n tüketiciye yönelik yükümlülüklerinin kapsam? geni?letilmi?tir. Hükmün önceki versiyonunda arac?l?k edenleri...