Solventless and Metal-Free Synthesis of High-Molecular-Mass Polyaminoboranes from Diisopropylaminoborane and Primary Amines

Nowadays, spider venom research focuses on the neurotoxic activity of small peptides. In this study, we investigated high-molecular-mass compounds that have either enzymatic activity or housekeeping functions present in either the venom gland or venom of Pamphobeteus verdolaga. We used proteomic and transcriptomic-assisted approaches to recognize the proteins sequences related to high-molecular-mass compounds present in either venom gland or venom. We report the amino acid sequences (partial or complete) of 45 high-molecular-mass compounds detected by transcriptomics showing similarity to other proteins with either enzymatic activity (i.e., phospholipases A2, kunitz-type, hyaluronidases, and sphingomyelinase D) or housekeeping functions involved in the signaling process, glucanotransferase function, and beta-N-acetylglucosaminidase activity. MS/MS analysis showed fragments exhibiting a resemblance similarity with different sequences detected by transcriptomics corresponding to sphingomyelinase D, hyaluronidase, lycotoxins, cysteine-rich secretory proteins, and kunitz-type serine protease inhibitors, among others. Additionally, we report a probably new protein sequence corresponding to the lycotoxin family detected by transcriptomics. The phylogeny analysis suggested that P. verdolaga includes a basal protein that underwent a duplication event that gave origin to the lycotoxin proteins reported for Lycosa sp. This approach allows proposing an evolutionary relationship of high-molecular-mass proteins among P. verdolaga and other spider species.

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Metal-Free Air Oxidation in a Convenient Cascade Approach for the Access to Isoquinoline-1,3,4(2H)-triones

Molecules ◽

10.3390/molecules24112177 ◽

2019 ◽

Vol 24 (11) ◽

pp. 2177

Author(s):

Antonia Di Mola ◽

Consiglia Tedesco ◽

Antonio Massa

Keyword(s):

Heterocyclic Compounds ◽

Aromatic Ketone ◽

Primary Amines ◽

Cascade Process ◽

Staudinger Reaction ◽

Caspase Inhibitor ◽

Air Oxidation ◽

Metal Free ◽

Free Air

Herein we describe a very useful application of the readily available trifunctional aromatic ketone methyl-2-(2-bromoacetyl)benzoate in reactions with primary amines. An unexpected in situ air oxidation that follows a cascade process allowed the access to a series of isoquinoline-1,3,4(2H)-triones, a class of heterocyclic compounds of great interest containing an oxygen-rich heterocyclic scaffold. A modification of the original protocol, utilizing a Staudinger reaction in the presence of trimethylphosphine, was necessary for the synthesis of Caspase inhibitor trione with free NH group.

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Mitigation of avian reproductive tract function by Salmonella enteritidis producing high-molecular-mass lipopolysaccharide

Environmental Microbiology ◽

10.1046/j.1462-2920.2002.00333.x ◽

2002 ◽

Vol 4 (9) ◽

pp. 538-545 ◽

Cited By ~ 16

Author(s):

Craig T. Parker ◽

Barry Harmon ◽

Jean Guard-Petter

Keyword(s):

Molecular Mass ◽

Salmonella Enteritidis ◽

Reproductive Tract ◽

High Molecular Mass ◽

Tract Function

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Identification of two highly sialylated human tear-fluid DMBT1 isoforms: the major high-molecular-mass glycoproteins in human tears

Biochemical Journal ◽

10.1042/bj20011876 ◽

2002 ◽

Vol 366 (2) ◽

pp. 511-520 ◽

Cited By ~ 63

Author(s):

Benjamin L. SCHULZ ◽

David OXLEY ◽

Nicolle H. PACKER ◽

Niclas G. KARLSSON

Keyword(s):

Molecular Mass ◽

Peptide Mass Fingerprinting ◽

High Molecular Mass ◽

Tear Fluid ◽

Protein Variant ◽

Peptide Mass ◽

Composite Gel ◽

Molecular Masses ◽

Protein Components ◽

Sialyl Lea

Human open eye tear fluid was separated by low-percentage SDS/PAGE to detect high-molecular-mass protein components. Two bands were found with apparent molecular masses of 330 and 270kDa respectively. By peptide-mass fingerprinting after tryptic digestion, the proteins were found to be isoforms of the DMBT1 gene product, with over 30% of the predicted protein covered by the tryptic peptides. By using gradient SDS/agarose/polyacrylamide composite gel electrophoresis and staining for glycosylation, it was shown that the two isoforms were the major high-molecular-mass glycoproteins of >200kDa in human tear fluid. Western blotting showed that the proteins expressed sialyl-Lea. After the release of oligosaccharides by reductive β-elimination from protein blotted on to PVDF membrane, it was revealed by liquid chromatography-MS that the O-linked oligosaccharides were comprised mainly of highly sialylated oligosaccharides with up to 16 monosaccharide units. A majority of the oligosaccharides could be described by the formula dHex0→2NeuAc1→xHexxHexNAcx(-ol), x = 1–6, where Hex stands for hexose, dHex for deoxyhexose, HexNAc for N-acetylhexosamine and NeuAc for N-acetylneuraminate. The number of sialic acids in the formula is less than 5. Interpretation of collision-induced fragmentation tandem MS confirmed the presence of sialic acid and suggested the presence of previously undescribed structures carrying the sialyl-Lea epitopes. Small amounts of neutral and sulphated species were also present. This is the first time that O-linked oligosaccharides have been detected and described from protein variant of the DMBT1 gene.

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