Basement membrane alterations after treatment with trypsin,hyaluronidase or collagenase

A transplantable rodent tumor producing multiple layers of basement membrane was used to study the effects of trypsin, hyaluronidase and collagenase on basement membranes. Treatment with trypsin resulted in an increase in the distance between adjacent lamellae and a loss of granular structures. Treatment with hyaluronidase separated basement membrane layers only in the outer lamellae, whereas collagenase resulted in extensively folded sheets which consisted predominantly of granules. From these findings it may be concluded that the granular structures represent the morphological equivalent of glycoproteins which are interlinked by a collagenous filamentous network. Hence, the BM represents a functional unit of proteoglycans, glycoproteins and collagen.     

Der bau der retina und der multiplen optischen papille bei zwei Synodontis-arten (teleostei,siluroidea)

The multiple optic papilla in the retina of two Synodontis species is described with special emphasis on the arrangement of the optic nerve fibers in fascicles. In a comparison of the eyes of the Brachiopterygei and Holostei with those of various Teleosts, the functional importance of these plesiomorphic structures is discussed.

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Abkürzungen in den Abbildungen A. h. Arteria hyaloidea - äFS äußere Faserschicht - äKS äußere Körnerschicht - Bi Bipolaren - C Cornea - Ch. dr. Chorioidaldrüse - Ch. g. Chorioidalgefäß - d dunkeladaptiert - F Faszikel - Fof Faszikel der Opticusfasern - Gkg Glaskörpergefäß - GZS Ganglienzellschicht - h helladaptiert - iFS innere Faserschicht - iKS innere Körnerschicht - Ir Iris - K Kern - l. b. lamina basalis - Li Linse - l. s. ligamentum suspensorium - MF Müllersche Faser - m. o. P. multiple opt. Papille - N. o. Nervus opticus - P. c. r. Pars coeca retinae - Sc Sclera - Stä Stäbchen - v. Au. Sp. ventraler Augenspalt - Z Zapfen Für die anregenden Diskussionen und die Unterstützung bei der Entstehung dieser Arbeit danke ich Herrn Dr. P. Kuenzer. Mein Dank gilt außerdem Fräulein M. v. Basse für die Anfertigung eines Teils der Präparate.     

The gene for Klebsiella bacteriophage K11 RNA polymerase: sequence and comparison with the homologous genes of phages T7, T3, and SP6

Summary We determined the nucleotide sequence of gene 1 of Klebsiella phage K11, which is a member of the T7 group of phages. The largest open reading frame corresponds to a polypeptide with 906 amino acids and a molecular weight of 100383 daltons. The deduced amino acid sequence of this polypeptide shows 71% homology to the T7 RNA polymerase (the product of T7 gene 1), 72% homology to the T3 RNA polymerase and 27% homology to the SP6 RNA polymerase. Divergent evolution was clearly most pronounced in the amino-terminal portion.     

The structure of nicotine blue from Arthrobacter oxidans

Summary Nicotine blue was separated into two major components. Their chromophores are anions of the diazadiphenoquinones (1) (nicotine blue I) and (2) (nicotine blue II). The dihydrate of the potassium salt of (1) is the major component of the extracellular crystals which are excreted on a solid medium. The acid-labile nicotine blue II is water-soluble and the main coloring agent of the agar and culture broth respectively.     

A regulatory network of two galectins mediates the earliest steps of avian limb skeletal morphogenesis

Background  

The skeletal elements of vertebrate embryonic limbs are prefigured by rod- and spot-like condensations of precartilage mesenchymal cells. The formation of these condensations depends on cell-matrix and cell-cell interactions, but how they are initiated and patterned is as yet unresolved.