Amino acid replacement in the protein S5 from a spectinomycin resistant mutant of Bacillus subtilis

Ribosomal protein S5 was isolated from wild type Bacillus subtilis ATCC 6633 and from a spectinomycin resistant mutant (BSPC 111) derived from spectinomycin sensitive to resistance is accomtrypsin and all the tryptic peptides were isolated by column- and paper-chromatography. By comparative amino acid analyses of the peptides, it was demonstrated that the S5 from the mutant differs from the wild type S5 by a replacement of one amino acid, namely lysine by isoleucine in the peptide T9. The results are compared with E. coli spectinomycin resistant mutants.

Proton magnetic resonance spectra of tetracyclic triterpene alcohols under the influence of a lanthanide shift reagent

The proton magnetic resonance spectra were measured for four series of tetracyclic triterpen-3beta-ols, i.e. 5alpha-lanostane, 5alpha-euphane, 5alpha-tirucallane, and 5alpha-dammarane series, in the presence of a molar equivalent of tris (dipivalomethanato) europium, a lanthanide shift reagent. The spectral pattern measured in the presence of the shift reagent was found useful for distinguishing each series and also for characterizing each skeletal isomer of tetracyclic triterpene alcohols.

24-Methylenedammarenol: a new triterpene alcohol from shea butter

A new triterpene alcohol was isolated from shea butter and its structure was shown to be 24-methylenedammarenol (24-methylene-5alpha-dammar-20[21]-en-3beta-o1). Dammaradienol (5alpha-dammara-20[21],24-dien-3beta-o1) also was isolated from shea butter.

The distribution of pyrophosphatidic acid in nature

The occurrence of a novel phospholipid, pyrophosphatidic acid, in the lipid extracts of yeasts (23 species), bacteria (E. coli), algae (chlorella), mammalia (human, rabbit, guinea pig, and mouse), insect (cockroach), fish (carp), mollusc (clam), and spermatophyta (spinach) was investigated. Pyrophosphatidic acid was found exclusively in the lipid extracts of several kinds of yeast species, but not in other normal living species (animals, plants, and microorganisms) so far investigated. All of the yeast species containing this lipid belong to the asporogenous yeasts (Cryptococcus neoformans CBS-132, Cryptococcus laurentii Z 6-5, Rhodotorula glutinis H 3-9-1, Rhodotorula rubra AY-2, Kloeckera apiculata KK-3, and Trichosporon cutaneum KC 4-3), and ballistosporogenous yeast (Sporobolomyces salmonicolor WF 174). In contrast, no detectable amount of pyrophosphatidic acid was found in the cellular lipids of ascosporogenous yeasts.

Analysis of methylsterol fractions from twenty vegetable oils

The 4-monomethylsterol and 4,4-dimethylsterol fractions were separated from the unsaponifiables of 20 vegetable oils by preparative thin layer chromatography, and their compositions were determined by gas liquid chromatography. Tentative identification of the individual components of these fractions was carried out by gas liquid chromatography and combined gas liquid chromatography-mass spectrometry. Among 4-monomethylsterols, obtusifoliol, gramisterol, and citrostadienol occur abundantly in most of the oils. Cycloeucalenol also occurs in some of the oils as a major component of 4-monomethylsterols. Other 4-monomethylsterols tentatively identified are: lophenol, 31-norlanosterol, 31-norcycloartenol, and 31-norlanostenol and/or 4alpha-methylzymostenol. Among 4,4-dimethylsterols, cycloartenol and 24-methylenecycloartanol followed by beta-amyrin and cycloartanol are common to most of the oils. Butyrospermol, alpha-amyrin, lupeol, and cyclobranol together with a 4,4-dimethylsterol, presumably lanostenol, occur in some of the oils. Cyclolaudenol is present in poppy seed oil. Besides these compounds, each of the oils contains some unidentified members of 4-monomethylsterols and 4,4-dimethylsterols. The methylsterol fraction of capsicum seed oil as compared with that of the other oils is characterized by its very high content of lophenol and cycloartanol together with three other members, presumably 31-norlanostenol, 4alpha-methylzymostenol, and lanostenol.

Excitation of an optical fiber by a Gaussian beam

In this paper we present the results of an in-depth analysis of the problem of Gaussian beam excitation of optical fibers at normal incidence. The method entails the application of the continuity conditions at the interface located at the fiber end using Gaussian beams with different spot sizes as our excitation source. Next, the simultaneous set of equations obtained is numerically solved for the reflected, guided, and radiated modal coefficients and their corresponding powers.

24-Methylenelanost-9(11)-en-3beta-ol, new triterpene alcohol from shea butter

A new triterpene alcohol was isolated fron shea butter and its structure was shown to be 24-methylenelanost-9(11)-en-3beta-ol. Gas chromatographic correlations between this triterpene alcohol and other related compounds are discussed.

Gas chromatographic differentiation of 4-desmethyl-, 4-monomethyl- and 4,4-dimethyl-sterols. Part II : differentiation of sterols based on deltaRAc-values on four stationary phases

The deltaRAc-values, i.e., ratios of retention data for sterol acetates to those for the corresponding free sterols, were determined for fourteen 4-desmethylsterols, seven 4-monomethylsterols and twenty-two 4,4-dimethylsterols on SE-30, OV-17, QF-1 and HiEFF-8B stationary phases. The QF-1 phase is found sperior to the others in affording the values which are the most effective for differentiation between the three sterol groups. Within the same sterol group, the values for individual sterol members on any of the stationary phases differ to some extent due to minor variations in their skeletal structure. These differences are useful for distinguishing individual members of the same sterol group differing in their skeletal structure, particularly in the position of double bond. The relative deltaRAc-values, i.e., ratios of deltaRAc-values of individual sterols to the deltaRAc-value of a standard sterol, are found almost independent upon the operating conditions of gas liquid chromatography and may be regarded as a characteristic value of sterols on one and the same stationary phase.

Postitional specificity of fatty acids in pyrophosphatidic acid from Cryptococcus neoformans

Pyrophosphatidic acid isolated from Cryptococcus neoformans was degraded to phosphatidic acid in aqueous pyridine. The phosphatidic acid was hydrolyzed by phospholipase A (EC 3.1.1.4) of Crotalus adamanteus to lysophosphatidic acid and 2-positioned fatty acids. From the analyses of the fatty acid composition of pyrophosphatidic acid and its degraded products (phosphatidid acid, lysophosphatidic acid, and fatty acid), it was concluded that most of the saturated fatty acids of pyrophosphatidic acid were at the 1,1'-positions while the unsaturated fatty acids were largely confined to the 2,2'-positions. The positional specificity of the fatty acids in pyrophosphatidic acid coincided with that of ordinary glycerophosphatides.

A mode of the growth of Mycobacterium lepraemurium in a cell-free liquid medium (38501)

The first report regarding in vitro growth patterns of M. lepraemurium was presented. Evidence is indicated that a growth mode of a single cell of M.lepraemurium in vitro is similar to that of culturable mycobacterium, especially atypical mycobacterium. This finding has added one property to characteristics of M. lepraemurium which have been already known.

Studies Relating to Aziridine Antitumor Antibiotics. Part I. Asymmetric Syntheses. Part II. Chiral Aziridines and their Conversion to α-Aminoacids

Separable diastereomeric cis-l-menthyl 2-phenyl-3-aziridinecarboxylates (4 and 5) were prepared by the Gabriel reaction. N-Acylation with p-nitrobenzoyl chloride or p-anisoyl chloride of 4 and 5 gives 7 and 8, and 23 and 24, respectively. Sodium iodide-catalyzed rearrangement of the N-acylated aziridines is regiospecific with exclusive attack at C-2 and from 8 is obtained the chiral 2-oxazolines cis-9 and trans-10 in a ratio of 30:70 together with the unsaturated amide 11. The structure of the latter was proven by independent synthesis. The intermediate l-menthyl N-p-nitrobenzoyl-3-iodophenyl-alaninate (18) was isolated at lower temperatures and shown to form the equilibrium mixture of 9 and 10 with triethylamine owing to partial racemization by a Finkelstein identity reaction. Use of an N-p-anisoyl substituent in the aziridine improves the yield of chiral 2-oxazolines by preventing the formation of 11, and allows the separation of pure cis- and trans-oxazolines for characterization. The aziridines bearing N-p-anisoyl substituents display a greater sensitivity to attack by weaker nucleophiles than the p-N-nitrobenzoyl analogs.Acid hydrolysis of 9 and 10 gives D-allo-β-phenylserine in an optical yield of about 17% from which 5 and 8 are tentatively assigned the 2R,3R configuration. Similar acid hydrolysis of the 2-p-anisyl-2-oxazoline (26b) allowed the isolation of the intermediate l-menthyl O-anisoyl-allo-β-phenylserinate (30a), hydrolysis of which gave D-allo-β-phenylserine in about 18% optical yield. The isolation of allo-β-phenylserine only from cis- and trans-2-oxazolines is attributed to acid-catalyzed inversion at the benzylic center to the conformationally more stable allo form.