Proses PEMBENTUKAN KOSAKATA DAN FUNGSI BAHASA KELOMPOK GAY

This study aims to describe vocabulary formations and language functions in a gay community. The object was the language employed by such a community. The data were collected through listening, recording, and noting and were analyzed by means of the qualitative descriptive technique. The data trustworthiness was enhanced by careful observations and triangulation (data sources, relevant theories, and other observers). The findings are as follows. First, the vocabulary formations include (a) form addition, (b) form substitution, (c) utilization of short forms (abbreviations and acronyms), and (d) utilization of puns. Second, language in the gay community has four functions, i.e.: (a) emotive function, (b) referential function,(c) phatic function, and (d) conative function.

Lactococcus lactis HemW (HemN) is a haem-binding protein with a putative role in haem trafficking

Lactococcus lactis cannot synthesize haem, but when supplied with haem, expresses a cytochrome bd oxidase. Apart from the cydAB structural genes for this oxidase, L. lactis features two additional genes, hemH and hemW (hemN), with conjectured functions in haem metabolism. While it appears clear that hemH encodes a ferrochelatase, no function is known for hemW. HemW-like proteins occur in bacteria, plants and animals, and are usually annotated as CPDHs (coproporphyrinogen III dehydrogenases). However, such a function has never been demonstrated for a HemW-like protein. We here studied HemW of L. lactis and showed that it is devoid of CPDH activity in vivo and in vitro. Recombinantly produced, purified HemW contained an Fe–S (iron–sulfur) cluster and was dimeric; upon loss of the iron, the protein became monomeric. Both forms of the protein covalently bound haem b in vitro, with a stoichiometry of one haem per monomer and a KD of 8 μM. In vivo, HemW occurred as a haem-free cytosolic form, as well as a haem-containing membrane-associated form. Addition of L. lactis membranes to haem-containing HemW triggered the release of haem from HemW in vitro. On the basis of these findings, we propose a role of HemW in haem trafficking. HemW-like proteins form a distinct phylogenetic clade that has not previously been recognized.

Engineered riboswitches control gene expression by small molecules

We have developed conditional gene expression systems based on engineered small-molecule-binding riboswitches. Tetracycline-dependent regulation can be imposed on an mRNA in yeast by inserting an aptamer in its 5′-untranslated region. Biochemical and genetic analyses determined that binding of the ligand tetracycline leads to a pseudoknot-like linkage within the aptamer structure, thereby inhibiting the initial steps of translation. A second translational control element was designed by combining a theophylline aptamer with a communication module for which a 1 nt slipping mechanism had been proposed. This structural element was inserted close to the bacterial ribosomal binding site at a position just interfering with translation in the non-ligand-bound form. Addition of the ligand then shifts the inhibitory element to a distance that permits efficient translation.

Lactate-Utilizing Bacteria, Isolated from Human Feces, That Produce Butyrate as a Major Fermentation Product

ABSTRACT The microbial community of the human colon contains many bacteria that produce lactic acid, but lactate is normally detected only at low concentrations (<5 mM) in feces from healthy individuals. It is not clear, however, which bacteria are mainly responsible for lactate utilization in the human colon. Here, bacteria able to utilize lactate and produce butyrate were identified among isolates obtained from 10−8 dilutions of fecal samples from five different subjects. Out of nine such strains identified, four were found to be related to Eubacterium hallii and two to Anaerostipes caccae, while the remaining three represent a new species within clostridial cluster XIVa based on their 16S rRNA sequences. Significant ability to utilize lactate was not detected in the butyrate-producing species Roseburia intestinalis, Eubacterium rectale, or Faecalibacterium prausnitzii. Whereas E. hallii and A. caccae strains used both d- and l-lactate, the remaining strains used only the d form. Addition of glucose to batch cultures prevented lactate utilization until the glucose became exhausted. However, when two E. hallii strains and one A. caccae strain were grown in separate cocultures with a starch-utilizing Bifidobacterium adolescentis isolate, with starch as the carbohydrate energy source, the l-lactate produced by B. adolescentis became undetectable and butyrate was formed. Such cross-feeding may help to explain the reported butyrogenic effect of certain dietary substrates, including resistant starch. The abundance of E. hallii in particular in the colonic ecosystem suggests that these bacteria play important roles in preventing lactate accumulation.

Penta-Coordinated Complexes of Bis(2,4-pentanedionato) Copper(II) with Some Oxygen Donor Organic Solvents

Bis(2,4-pentanedionato) Copper(II) reacts with some oxygen donor organic solvents to form addition complexes with general formula, Cu(2,4-pentanedionato)2. L (where L = MeOH, EtOH, PriOH, ButOH, THF, MeCOMe, MeCOEt and MeCOPrn). The complexes were recrystallized and characterized by the elemental analyses, infrared and electronic spectra, molecular weight and magnetic measurements.

Reactions of Dichloroxozirconium(IV) Octahydrate with Monocarboxylic Acid Chlorides

Dichloroxozirconium(IV) octahydrate reacts with acetyl, propionyl, butyryl and chloracetyl chlorides at low temperatures to form addition compounds of the parent carboxylic acid, ZrOCl2 · 2 RCO2H, but at higher temperatures the corresponding carboxylates of the type ZrO(RCO2)2 · RCO2H are obtained. Benzoyl chloride does not react at low temperatures, but at 60 °C gives an addition product ZrOCl2 · 2 C6H5CO2H, and at higher temperatures a substitution product ZrO(C6H5CO2)2 · 2 C6H5CO2H is obtained. Elemental analyses, molar conductance measurements, infrared spectral studies and thermal decompositions have been carried out to understand the nature of these compounds.

The mechanism of the inhibition of the mitochondrial pyruvate transportater by α-cyanocinnamate derivatives

Pyruvate transport into rat liver mitochondria is inhibited by a variety of thiol reagents. alpha-Cyanocinnamate and its derivates, potent and reversible inhibitors of pyruvate transport, react reversibly with mercaptoethanol and cysteine to form addition products. It is concluded that these inhibitors react with an essential thiol group on the pyruvate carrier.