MORPHOLOGICAL AND CHEMICAL STUDIES OF COLLAGEN FORMATION : I. The Fine Structure of Guinea Pig Granulomata

This paper describes electron microscopic studies of developing connective tissue in granulomata induced by the subcutaneous injection of carrageenin into guinea pigs. Seven days after injection the granulomata contained many fibroblasts and exhibited rapid production of collagen. The fibroblasts were characterised by an extensively developed endoplasmic reticulum and showed numbers of fine, unstriated filaments in the outer regions of the cytoplasm. The filaments, about 50 A in diameter, tended to lie parallel to and closely adjacent to the cell boundary. The cytoplasmic membrane was frequently ill defined or disrupted, particularly bordering regions in which filaments occurred. In longitudinal sections of extended cell processes, filaments were abundant and, in some instances, the cytoplasmic membrane was barely detectable. In the extracellular space striated collagen fibrils were usually accompanied by filaments, 50 to 100 A in diameter, and these often exhibited the characteristic periodicity of collagen, particularly after intense electron bombardment. Much cellular debris was present in the extracellular space. These observations have led to the suggestion that connective tissue precursors are released from fibroblasts by the disintegration or dissolution of the cytoplasmic membrane and the shedding of cytoplasmic material, as in the apocrine gland cells. In some instances this release may take the form of the elongation from the cell of extended processes; disintegration of the cytoplasmic membrane surrounding these processes then leaves the contents in the extracellular phase.     

MORPHOLOGICAL AND CHEMICAL STUDIES OF COLLAGEN FORMATION : II. Metabolic Activity of Collagen Associated with Subcellular Fractions of Guinea Pig Granulomata

Electron micrographs of thin sections of nuclear, microsomal, and mitochondrial fractions obtained from a carrageenin-induced granuloma showed considerable contamination of the heavier by the lighter fractions. Striated collagen fibrils could be identified in the nuclei + debris fraction. Only a few striated fibrils occurred in the mitochondrial fraction; very fine filaments (diameter 50 A) could be seen in this fraction, but could not be distinguished with certainty from fibrillar material derived from broken nuclei. 35 per cent of the mitochondrial and 80 per cent of the microsomal collagen was extractable by 0.2 M NaCl and could be purified by the standard methods of solution and reprecipitation. The amino acid composition of these collagen fractions determined by ion exchange chromatography was within the range normally found for collagen and gelatin from other mammalian species, allowing for 10 to 20 per cent of some non-collagenous contaminant of the microsomal collagen. Hydroxyproline and proline were isolated by chromatography on paper from hydrolysates of the nuclear, mitochondrial, and microsomal collagen fractions, after incubation of tissue slices with L-¹⁴C-proline. The specific activities of the hydroxyproline from these collagens were in the approximate ratio 1:2:6, while that of bound hydroxyproline derived from the supernatant was only 1, indicating primary synthesis of collagen in the microsomes. Attempts to demonstrate incorporation of L-¹⁴C-proline into collagen or into free hydroxyproline in cell free systems were unsuccessful, nor was it possible to demonstrate non-specific incorporation of L-¹⁴C-valine into TCA-insoluble material by various combinations of subcellular fractions.     

CHEMICAL AND MORPHOLOGICAL STUDIES ON THE IN VITRO CALCIFICATION OF AORTA

After a lag period, rat aortas incubated in rat serum in vitro accumulated substantial quantities of calcium and phosphate. Examination of the tissue by x-ray diffraction, microradiography, electron diffraction, and electron microscopy indicated that the calcium-phosphate phase which formed was hydroxyapatite and that the crystals were localized almost exclusively in elastin. Selective elimination of various components of the aorta with proteolytic enzymes indicated that the presence of elastin was required for mineralization. Collagen fibers did not appear to be required for the initiation of calcification, nor did they seem to undergo appreciable calcification in the time periods studied. Analysis of the initial lag period suggested that at least two changes occurred in serum prior to the mineralization of this tissue. Inhibitors of the reaction were destroyed, and the level of dialyzable calcium was elevated owing to its release from serum protein.     

FORMATION AND STRUCTURE OF THE SPORE OF BACILLUS COAGULANS

Spore formation in Bacillus coagulans has been studied by electron microscopy using an epoxy resin (Araldite) embedding technique. The developmental stages from the origin of the initial spore septum to the mature spore were investigated. The two forespore membranes developed from the double layer of cytoplasmic membrane. The cortex was progressively deposited between these two membranes. The inner membrane finally became the spore protoplasmic membrane, and the outer membrane part of the inner spore coat or the outer spore coat itself. In the mature spore the completed integuments around the spore protoplasm consisted of the cortex, a laminated inner coat, and a dense outer coat. No exosporium was observed. The method of formation of the cortex and the spore coats is discussed.     

黄瓜去顶苗直接成花的形态学研究

本文对黄瓜0—7天幼苗及去顶后0—8天诱导花芽分化苗与诱导营养芽分化苗的子叶节进行了系统石蜡切片观察,未发现0—7天幼苗的子叶叶腋存在潜伏芽。去顶后1—2天在子叶叶柄基部与切口之间的表皮下细胞分裂形成突起,去顶后6天诱花苗与诱芽苗的突起表现出形态差异,诱花苗突起的上端变钝,而诱芽苗突起的上端成尖锥状。去顶后8天诱花苗在子叶叶柄与切口之间形成完整的花芽。另发现有少量花芽起源于切口处细胞。对去顶后0—6天诱花苗与诱芽苗的子叶节还进行了电镜扫描观察,观察结果与石蜡切片基本一致。     

PARTICIPATION OF THE CYTOPLASMIC MEMBRANE IN THE GROWTH AND SPORE FORMATION OF BACILLI

A polyester embedding technique was used to study the early stages of spore formation in members of the genus Bacillus in order to investigate further the origin and nature of the initial spore septum and the resulting forespore envelope. Whereas previously, with a methacrylate procedure, this layer had appeared to be continuous with the cell wall, this study reveals it as a double layer of cytoplasmic membrane. Perisporal, membranous organelles connected both to the developing forspore envelope and to the cytoplasmic membrane were encountered in the four species studied. Similar organelles were prominent during growth at the sites of transverse septa formation. These were connected to, or continuous with, the cytoplasmic membrane and often adherent to the chromatin bodies of the dividing bacilli.     

7种獐牙菜属药用植物形态组织学研究

本文报道了水灵芝(Swertia davidii Franch)、双斑獐牙菜(S.bimaculata(S.et Z.)HK.f.Thoms)、江浙獐牙菜(S.hickinii Burk)、贵州獐牙菜(S.koui-tchensis Franch)、大籽獐牙菜(S.macrosperma C.B.Clarke)、翼梗獐牙菜(S.nervosa Wall)、紫红獐牙菜(S.punicea Hemsl.)等7种獐牙菜属药用植物的药材性状、根茎叶的显微构造和解离组织及粉末特征,为合理开发和利用这一药物资源提供了鉴别依据,也为獐牙菜属植物的形态组织学研究提供了有价值的资料。     

STUDIES ON THE BACTERIAL DIE-BACK AND CANKER DISEASE OF POPLAR

Artificial freezing caused leaf necrosis and twig die-back but did not produce cracks or cankers on living branches of three varieties of poplar. Freezing increased the damage caused by a well-established infection of the bacterial die-back and canker but checked new lesions. Freezing prior to infection has no appreciable effect on the establishment of the disease.     

黄杨花蜜腺的形态解剖学研究

黄杨花单性,雌雄同株,雄花花蜜腺４枚,乳头状,着生于退化雌蕊子房顶部;雌花花蜜腺３枚,短柱状,位于３枚花柱之间。雌、雄花蜜腺均由分泌表皮、产蜜组织和维管束构成,在发育过程中产蜜组织细胞的液泡都发生有规律的变化。雌花蜜腺大,属非淀粉型蜜腺,泌蜜量大,蜜汁含糖分多,维管束中仅含韧皮部;雄花蜜腺小,属淀粉型蜜腺,泌蜜量小．蜜汁含糖量小,维管束由木质部和韧皮部构成。     

STUDIES IN THE BACTERIAL DIE-BACK AND CANKER DISEASE OF POPLAR

The bacterial die-back and canker of poplar is characterized by dark necrotic areas in the leaves, die-back accompanied by cracks in the bark of 1–4-year-old branches, and by cankers on the trunk and branches of different ages. The cankers may be 'closed' or 'open' and when moist exude slime containing bacteria.
The disease is caused by Pseudomonas syringae f. sp. populea , a new forma specialis closely resembling Ps. syringae in bacteriological characters but differing from it in parasitism. The association of the slime with the bacteria is essential for the production of typical lesions.
Inoculations with the pathogen alone, or in association with other organisms produce atypical symptoms.
The bacteria attack the cortical parenchyma and occasionally invade the xylem vessels.     

细菌铁蛋白氧化还原特性及电极活性的研究

棕色固氮菌细菌铁蛋白能直接快速地从金属铂电极上得到电子或提供电子给铂电极。经－６００ｍＶ（相对于ＮＨＥ）还原电位处理后,还原态细菌铁蛋白在可见光谱区中（３８０－５８０ｎｍ）所呈现的整体吸收光谱强度明显高于氧化态细菌铁蛋白的吸收光谱强度。经氯化钴处理后的细菌铁蛋白表现出较弱的电极活性及释放铁的速率明显下降。此外,细菌铁蛋白在体外模拟棕色固氮菌整体细胞内的微量氧环境体系中仍有氢还原现象,因而推测细菌铁蛋白在该菌体内也能进行吸氢反应。细菌铁蛋白是一种类似有吸氢氢酶功能的蛋白质     

STUDIES ON BIOLUMINESCENCE : IX. CHEMICAL NATURE OF CYPRIDINA LUCIFERIN AND CYPRIDINA LUCIFERASE.

There seems to be very little doubt but that luciferase is a protein or so closely associated with proteins that their removal destroys its characteristic properties. The particular group of proteins to which it belongs may be arrived at by a process of exclusion, and only the group of albumins has properties which agree completely with those of luciferase. Dubois believes Pholas luciferase to be an oxidizing enzyme similar to the oxydones of Battelli and Stern because it is readily destroyed by fat solvents such as chloroform, strong alcohol, etc. He has detected iron in a luciferase solution which has dialyzed against running water for a long time, and believes it to be made up of protein in combination with iron and to act as an "oxyzymase ferrique." Cypridina luciferase, on the other hand, is not readily destroyed by fat solvents. Toluene and chloroform are good preservatives, and I often make use of them for this purpose, keeping the luciferase solutions for many months. Professor A. H. Phillips of Princeton University has very kindly analyzed some whole dried Cypridinœ for me and finds iron, copper, and manganese but no zinc or vanadium to be present. Whether these metals are connected with the action of Cypridina luciferase is uncertain, but it is significant that all three of the metals thought to be concerned in organic oxidations are present. Although a large amount of luciferin mixed with a small amount of luciferase will use up all the latter, I agree with Dubois that luciferase has sufficient properties in common with the enzymes as a class to be considered an enzyme. The peroxidases are well known to be used up in the reactions they accelerate. All workers on enzymes agree that the more enzymes are purified the less active they become. The chemical procedures necessary to remove foreign material bring about irreversible changes in the enzyme itself, a characteristic also of many protein groups and of the colloidal state in general. This is true in the case of luciferase, for the crude luciferase solution is the most active preparation that can be obtained. I believe that Cypridina luciferase should be placed in a class of oxidizing enzymes by itself—a group having the chemical reactions of an albumin, possibly in combination with some heavy metal, and which as far as we know, acts specifically on only one substance, Cypridina luciferin. It resembles the plant peroxidases in resisting the action of chloroform, toluene, etc., but will not oxidize any of the hydroxyphenol or aminophenol compounds so readily oxidized by the peroxidases, nor will the peroxidases oxidize luciferin with light production. Dubois'' researches show that Pholas luciferase differs in some properties from Cypridina luciferase, and my own work indicates that firefly luciferase is more like that of Pholas. A comparative study of other species of luminous animals is needed in order to delimit more accurately the class of luciferases as a whole. Luciferin presents many characteristics in common with the proteins, but two, which, to say the least, throw doubt on its protein nature: (1) its peculiar solubility (in alcohols, esters, and glacial acetic acid), (2) and its resistance to digestion by proteases, even by trypsin which has almost universal digestive action. These two peculiarities have been discussed above. We can only say that if a protein, luciferin must belong to a new group differing from known natural proteins in these respects. In general characteristics this new group would fall somewhere on the border-line between the proteoses and peptones. It would not be surprising to find in nature proteoses or peptones soluble in absolute alcohol. We know also that some NH-CO linkages of proteins are broken down with great difficulty by trypsin as it is difficult to obtain a tryptic digest of protein which does not give the biuret reaction, and the work of Fischer and Abderhalden has shown that certain artificial polypeptides are not digested by pure activated pancreatic juice. We have, then, three possibilities. Luciferin is (1) either a natural proteose not attacked by trypsin, or (2) if attacked by trypsin, its decomposition products (presumably amino-acids) still contain the group oxidizable with light production, or (3) it is not a protein at all. I believe that luciferin has too many protein characteristics to conform to the last possibility. I have been unable to oxidize with light production various mixtures of amino-acids (from beef and casein) by means of luciferase and consequently am led to believe that luciferin is a new natural proteose, soluble in absolute alcohol and not digested by trypsin. Dubois believes Pholas luciferin to be a natural albumin with acid properties. Cypridina luciferin could not possibly be regarded as an albumin, but it is very likely that the luciferins of different species of luminous animals differ in certain characteristics. As in the case of the luciferases, we know that the luciferins are not identical substances, and only future work can determine in what particulars they differ. A summary of the properties of Cypridina luciferin and Cypridina luciferase will be found in the tables accompanying this paper.