We observed three AGN from the Parkes Half-Jansky Flat-spectrum Sample at nearinfrared (NIR) wavelengths to search for micro-variability. In one source, the blue quasar PKS 2243−123, good evidence for NIR micro-variability was found. In the other two sources, PKS 2240−260 and PKS 2233−148, both BL Lacertae objects, no such evidence of variability was detected. We discuss the implications of the...

BACKGROUND The structural and catalytic similarities between modular nonribosomal peptide synthetases (NRPSs) and polyketide synthases (PKSs) inspired us to search for a hybrid NRPS-PKS system. The antitumor drug bleomycin (BLM) is a natural hybrid peptide-polyketide metabolite, the biosynthesis of which provides an excellent opportunity to investigate intermodular communication between NRPS an...

The whiE gene cluster of Streptomyces coelicolor is normally expressed shortly before sporulation in the aerial mycelium, leading to production of the grey polyketide spore pigment. By placing the whiE genes under the control of the thiostrepton-inducible tipA promoter, they were artificially expressed on plasmids or in the chromosome during vegetative growth in a strain deleted for the act gen...

According to unified schemes for Active Galactic Nuclei, low-power, Fanaroff-Riley type I (FR I), radio galaxies are thought to be BL Lacs with their jets pointing at relatively large angles with respect to the line of sight. X-ray observations of FR I sources can test this scenario and constrain the presence of obscuring material around the nucleus. In this paper we discuss the X-ray propertie...

The enediynes, unified by their unique molecular architecture and mode of action, represent some of the most potent anticancer drugs ever discovered. The biosynthesis of the enediyne core has been predicted to be initiated by a polyketide synthase (PKS) that is distinct from all known PKSs. Characterization of the enediyne PKS involved in C-1027 (SgcE) and neocarzinostatin (NcsE) biosynthesis h...

This paper presents information on the physical and mechanical properties of different sizes of palm kernel shells (PKS) used here as lightweight aggregates (LWA) and their influence on mechanical properties of palm kernel shell concrete (PKSC). Silica fume and fly ash were used as cementitious materials and all mixes had 1% superplasticizer on cement weight. It has been found that PKS consists...

Strains of Lactococcus lactis isolated from plant tissues possess adaptations that support their survival and growth in plant-associated microbial habitats. We previously demonstrated that genes coding for a hybrid nonribosomal peptide synthetase/polyketide synthase (NRPS/PKS) system involved in production of an uncharacterized secondary metabolite are specifically induced in L. lactis KF147 du...

The Pallister-Killian syndrome (PKS) is an extremely rare genetic disorder with an incidence estimated around 1/25000. PKS is a multiple congenital anomaly deficit syndrome caused by mosaic tissue limited tetrasomy for chromosome 12p. The presented report is the first confirmed case with PKS in Turkey. This report focuses on the orofacial clinical manifestations of an 6-year-old boy with PKS wh...

Phototropism allows plants to orient their photosynthetic organs towards the light. In Arabidopsis, phototropins 1 and 2 sense directional blue light such that phot1 triggers phototropism in response to low fluence rates, while both phot1 and phot2 mediate this response under higher light conditions. Phototropism results from asymmetric growth in the hypocotyl elongation zone that depends on an...

Carrier proteins (CPs) play a critical role in the biosynthesis of various natural products, especially in nonribosomal peptide synthetase (NRPS) and polyketide synthase (PKS) enzymology, where the CPs are referred to as peptidyl-carrier proteins (PCPs) or acyl-carrier proteins (ACPs), respectively. CPs can either be a domain in large multifunctional polypeptides or standalone proteins, termed ...