region 190-210 mjA was determined by Dr C. von Planta (Hoffmann-La Roche and Co., Basle) using a vacuum grating spectrometer as described by Planta (1962). Infrared-absorption spectra were recorded by a Perkin-Elmer Infracord (model 137) spectrometer. The highresolution spectra were obtained by Dr C. H. Steele of the Thornton Research Laboratories, Shell, Ellesmere Port, Cheshire, with a Grubb-Parsons double-beam grating spectrometer (model GS 2). Samples were examined as films between NaCl plates whenever possible. Materials of high melting point were studied as KBr disks.

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When pig liver microsomal preparations were incubated with GDP-[(14)C]mannose, 10-40% of the (14)C was transferred to mannolipid and 1-3% to mannoprotein. The transfer to mannolipid was readily reversible and GDP was one of the products of the reaction. It was possible to reverse the reaction by adding excess of GDP and to show the incorporation of [(14)C]GDP into GDP-mannose. When excess of unlabelled GDP-mannose was added to a partially completed incubation there was a rapid transfer back of [(14)C]mannose from the mannolipid to GDP-mannose. The other product of the reaction, the mannolipid, had the properties of a prenol phosphate mannose. This was illustrated by its lability to dilute acid but stability to dilute alkali, and by its chromatographic properties. Dolichol phosphate stimulated the incorporation of [(14)C]mannose into both mannolipid and into protein, although the former effect was larger and more consistent than the latter. The incorporation of exogenous [(3)H]dolichol phosphate into the mannolipid, and its release, accompanied by mannose, on treatment of the mannolipid with dilute acid, confirmed that exogenous dolichol phosphate can act as an acceptor of mannose in this system. It was shown that other exogenous polyprenol phosphates (but not farnesol phosphate or cetyl phosphate) can substitute for dolichol phosphate in this respect but that they are much less efficient than dolichol phosphate in stimulating the transfer of mannose to protein. Since pig liver contained substances with the chromatographic properties of both dolichol phosphate and dolichol phosphate mannose, which caused an increase in transfer of [(14)C]mannose from GDP-[(14)C]mannose to mannolipid, it was concluded that endogenous dolichol phosphate acts as an acceptor of mannose in the microsomal preparation. The results indicate that the mannolipid is an intermediate in the transfer of mannose from GDP-mannose to protein. Some 4% of the mannose of a sample of mannolipid added to an incubation was transferred to protein. A scheme is proposed to explain the variations with time in the production of radioactive mannolipid, mannoprotein, mannose 1-phosphate and mannose from GDP-[(14)C]mannose that takes account of the above observations. ATP, ADP, UTP, GDP, ADP-glucose and UDP-glucose markedly inhibited the transfer of mannose to the mannolipid.

Extracellular a-galactosidase A was purified from the culture filtrate of an over-producing strain of Aspergillus niger containing multiple copies of the encoding aglA gene under the control of the glucoamylase (glaA) promoter. Endoglycosidase digestion followed by SDS/PAGE, lectin and immunoblotting suggested that glycosylation accounted for < 25% of the molecular size of the purified protein. Monosaccharide analysis showed that this was composed of N-acetyl glucosamine, mannose and galactose. Mild acid hydrolysis, mild methanolysis, immunoblotting and exoglycosidase digestion indicated that the majority of the galactosyl component was in the furanoic conformation (b-d-galactofuranose, Galf). At least 20 different N-linked oligosaccharides were fractionated by high-pH anion-exchange chromatography following release from the polypeptide by peptide-N-glycosidase F. The structures of these were subsequently determined by fast atom bombardment mass spectrometry to be a linear series of Hex 7226 HexHAc 2 . Indicating that oligosaccharides from GlcNAc 2 Man 7 , increasing in molecular size up to GlcNAc 2-Man 24 were present. Each of these were additionally substituted with up to three b-Galf residues. Linkage analysis confirmed the presence of mild acid labile terminal hexofuranose residues. These results show that filamentous fungi are capable of producing a heterogeneous mixture of high molecular-size N-linked glycans substituted with galactofuranoic residues, on a secreted glycoprotein.

Evidence from mass, nuclear-magnetic-resonance and infrared spectrometry and from gas-liquid and thin-layer chromatography is presented in favour of the presence of cis-trans-decaprenol, -undecaprenol and -dodecaprenol in the mixture of polyprenols (2.6mg./g.) isolated from leaf tissue of Ficus elastica. The trivial names ficaprenol-10, -11 and -12 are proposed. Nuclear-magnetic-resonance studies showed that each of these prenols contains three trans internal isoprene residues and a cis ;OH-terminal' isoprene residue. Ficaprenol-11 is the major component of the mixture. Chromatographic evidence suggests the presence also of small amounts of ficaprenol-9 and -13. The precise position of the three trans internal isoprene residues was not determined but it is suggested that these are adjacent to the omega-terminal isoprene residue and that the ficaprenols are formed from all-trans-geranylgeranyl pyrophosphate. It is also suggested that ficaprenol-10, -11, -12 and -13 are probably the same compounds as castaprenol-10, -11, -12 and -13.

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Evidence for the presence of undecaprenol in the unsaponifiable lipid of Lactobacillus plantarum (N.C.I.B. 6376) is presented. Characterization of the compound was based mainly on mass, i.r. and n.m.r. spectrometry. The prenol was isolated at a concentration of 40mug/g wet wt. of bacteria and contained over 90% (1.0-5.4% of the dose) of the (14)C present in the unsaponifiable lipid after incubation of the bacteria with [2-(14)C]mevalonate. N.m.r. spectrometry indicated the presence of two internal trans-, one alpha-cis- and seven internal cis-isoprene residues per molecule. The (3)H/(14)C ratios of the prenol after incubation of the bacteria with [2-(14)C,(4R)-4-(3)H(1)]- and [2-(14)C,(4S)-4-(3)H(1)]-mevalonate were in agreement with this stereochemistry. There was no evidence of saturated isoprene residues in the molecule. The undecaprenol appeared to be accompanied by much smaller quantities of decaprenol and nonaprenol.