摘要:

Fructose served as sole carbon source for the growth ofRhodospirillum rubrumanaerobically under light or aerobically in the dark while glucose did not. Glucose was not utilized by the organism at all. Radiorespirometric studies, using14C specifically labelled fructose as substrate, revealed that fructose is catabolized exclusively via the Embden–Meyerhof–Parnas (EMP) glycolytic pathway. BothL-glutamic andD-glutamic acids can be utilized by this organism, via the tricarboxylic acid cycle (TCA) pathway, under either aerobic-dark or anaerobic-light conditions.

ISSN:0008-4166    

DOI:10.1139/m68-084

出版商:NRC Research Press    

年代:1968

数据来源: NRC

摘要:

Cell-free extracts of tumor cells induced by adenovirus-12 derived from Syrian hamsters possessed higher transfer RNA (tRNA) methylase activity than cell-free extracts from liver, lung, kidney, spleen, or skin and muscle. No difference was found between normal and tumor cell free extracts in the methylation of DNA or ribosomal RNA.ThetRNA methylase activities in cell-free extracts from hamster embryos were in the range found for normal adult tissue extracts. It appears therefore that the increase intRNA methylase is characteristic of the tumor cells, and is not a result of their rapid growth.

ISSN:0008-4166    

DOI:10.1139/m68-085

出版商:NRC Research Press    

年代:1968

数据来源: NRC

摘要:

A survey of the content and composition of lipids from isolated cell walls ofPseudomonas aeruginosaandBrucella abortuswas made. The following results are average values from several experiments. The readily extractable lipids made up 15.7% and the firmly bound lipids 8.7% of the dry weight of the cell walls ofP.aeruginosa. The readily extractable lipids ofB.abortuscell walls accounted for 11.4% and the firmly bound lipids 6.4% of the dry weight of the walls.The readily extractable lipids were further separated into phospholipids, free fatty acids, and neutral lipids. These lipids ofP.aeruginosacell walls contained 44.9% phospholipids and 52.9% free fatty acids and neutral lipids. InB.abortuscell walls the phospholipids accounted for only 22.1% of the free lipids whereas the free fatty acids and neutral lipids made up 76.1%.The phospholipids ofP.aeruginosaandB.abortuswere shown by thin-layer chromatography to be composed of four and seven components respectively. The bulk of the phospholipids was phosphatidyl ethanolamine and diphosphatidyl glycerol of the cardiolipin type. Lysophosphatidyl ethanolamine was also present in both organisms. The presence of phosphatidyl choline could not be demonstrated conclusively since choline could not be detected in the hydrolytic products of the phospholipids; however, infrared spectra of the total lipids and of the phospholipids of bothP.aeruginosaandB.abortusshowed absorption bands at 970 cm−1which are characteristic of phosphatidyl choline.Gas–liquid chromatography of the free fatty acids ofP.aeruginosashowed the major portion of these acids to be C16and C18saturated and monounsaturated fatty acids. The bulk of the free fatty acids ofB.abortusconsisted of C18saturated, monounsaturated, and polyunsaturated (C18:2) together with lesser amounts of C16saturated and monounsaturated acids. Two components were tentatively identified as C19cyclopropane and C19:0fatty acids respectively. Small amounts of both C12and C14saturated fatty acids were found in both organisms. No hydroxy fatty acids could be identified in eitherP.aeruginosaorB.abortus.Calcium and magnesium, determined by atomic absorption spectrophotometry, were associated with all the phospholipid components in both organisms. However, the largest quantities of calcium and magnesium were found in the phospholipid components, phosphatidyl ethanolamine and diphosphatidyl glycerol. Trace amounts of zinc were present in all phospholipid components of the cell walls of both microorganisms. Manganese was not detected.

ISSN:0008-4166    

DOI:10.1139/m68-086

出版商:NRC Research Press    

年代:1968

数据来源: NRC

摘要:

Using enrichment culture technics a species ofAlcaligenes(M1) was isolated from soil which was able to utilize mercaptosuccinic acid (MS) as a sole source of carbon, sulfur, and energy. Growth on a MS–salts basal medium was not significantly enhanced by single supplements of B-vitamins or by yeast extract. Comparative studies on succinate and MS oxidation byAlcaligenesandPseudomonas aeruginosaindicated that MS was an inhibitor of succinate oxidation by resting cells of both microorganisms when they were grown in a medium lacking mercaptosuccinic acid such as a succinate–salts basal. However, when M1was grown on MS, it was able to oxidize both succinate and MS, thereby indicating that the MS oxidase system was inducible. In addition, the MS oxidase system in cell-free extracts of M1was relatively insensitive to 10–30 μmoles of malonate, whereas the succinoxidase system was inhibited 66% by 30 μmoles of the inhibitor. Cell-free extracts of succinate-grown cells ofP.aeruginosawere unable to oxidize MS, indicating that the inactivity of resting cells was not due to a permease problem. Investigation of the metabolic fate of the sulfur moiety of MS by growing cells of M1indicated that all of the available sulfur was liberated as inorganic sulfate, while no free sulfide was detected. Thiosulfate sulfurtransferase (rhodanese) was detected in extracts from cells grown both with and without mercaptosuccinic acid. However, growth in the MS medium enhanced the production of rhodanese approximately 40%. In addition, thiosulfate oxidase activity was also detected in resting cells and cell-free extracts prepared from MS-grown cells, but not from cells grown without mercaptosuccinic acid.

ISSN:0008-4166    

DOI:10.1139/m68-087

出版商:NRC Research Press    

年代:1968

数据来源: NRC

摘要:

The density gradient centrifugation of the histamine-sensitizing factor (HSF) ofB.pertussisextracts in admixture with purified foreign proteins has revealed a property of the HSF not previously recognized. The HSF sedimentation was markedly accelerated in the presence of human serum macroglobulin and hog thyroglobulin. The absence of gross detectable changes in the protein profiles after the displacement of the HSF by sedimentation suggests the need for studies on the chemical composition of the HSF.The affinity of the HSF towards the foreign proteins, particularly those of large molecular size, has suggested a useful model by which the relationship of the HSF to other biological activities ofB.pertussismay be studied.

ISSN:0008-4166    

DOI:10.1139/m68-088

出版商:NRC Research Press    

年代:1968

数据来源: NRC

摘要:

Spores ofA.ochraceuswere used to transform a variety of steroids into their 11α-hydroxy derivatives. Physicochemical data of some new 11α-hydroxy derivatives are presented. Specificity ofA.ochraceusin relation to steroid transformations is discussed.

ISSN:0008-4166    

DOI:10.1139/m68-089

出版商:NRC Research Press    

年代:1968

数据来源: NRC

摘要:

A rapid and sensitive assay method has been developed for influenza (A/PR8) virus in abortively infected African green monkey kidney cells. Using immunofluorescence, primarily infected cells could be scored within 12–13 hours after virus inoculation. It has been demonstrated that this technique gives reproducible results and exhibits a direct relationship between virus concentration and the number of fluorescent cells. The assay system has been shown to be more sensitive than the quantitative hemadsorption technique.

ISSN:0008-4166    

DOI:10.1139/m68-090

出版商:NRC Research Press    

年代:1968

数据来源: NRC

摘要:

Twenty-four different patterns of single and multiple requirements for various B vitamins were demonstrated for 665 cultures of marine bacteria grown in a basal synthetic seawater medium enriched with phosphate, vitamin-free casamino acids, dextrose, and succinate. Among 114 thiamine-requiring isolates, 55 were unable to make the pyrimidine moiety, 19 required thiazole, 13 needed both thiazole and the pyrimidine moiety, while 27 organisms required thiamine or thiamine pyrophosphate for growth. Among 142 biotin requirers, 22 had to be supplied with biotin, 60 could use either biotin or biocytin, 54 were able to respond to either biotin, biocytin, or desthiobiotin. Only six cultures could not use biocytin, and required either biotin or desthiobiotin. Various responses of vitamin B12requiring cultures indicated special types of specificity for cyanocobalamin and analogues of this vitamin. Computer-sorting at the 0.66 similarity coefficient breaking point arranged a group of 104 isolates into eight clusters. The isolates having biotin or thiamine requirements, single or in combination with other vitamin needs, appeared to be randomly scattered through the eight clusters.

ISSN:0008-4166    

DOI:10.1139/m68-091

出版商:NRC Research Press    

年代:1968

数据来源: NRC

摘要:

The development of natural bactericidal antibody levels in the piglet was studied and bactericidal antibody levels in newborn serum, maternal serum, and colostrum of the pig were determined. Natural bactericidal antibody levels in serum of the newborn piglet before ingestion of colostrum were extremely low and, as in adult serum, dependent upon natural antibody and complement for its activity. When the animals were 1 year old, large variations in natural antibody levels were found in those of a single litter. The levels of natural antibody in maternal serum, colostrum, and precolostral newborn serum did not reveal a positive correlation. Finally, immunization of gilts before delivery provided a very effective antigenic stimulus in the piglets whose antibody titer, when the animals were 2 weeks old, was comparable to that of the immunized parent.

ISSN:0008-4166    

DOI:10.1139/m68-092

出版商:NRC Research Press    

年代:1968

数据来源: NRC

摘要:

Colony changes from rough to smooth were observed in a rough strain of mycobacterium ATCC 607 after exposure to phages D29 and B4. The colonies surviving after exposure to these two phages were both smooth and lysogenic. Increased nitrate reductase and Tween 80 hydrolytic activities accompanied lysogenization. Loss of lysogeny was accompanied by conversion to the rough colony type and a decrease in nitrate reductase and Tween 80 hydrolytic activities. The rapid loss and gain of these multiple characteristics suggested that the genetic control lies in a plasmid of mycobacteria.

ISSN:0008-4166    

DOI:10.1139/m68-093

出版商:NRC Research Press    

年代:1968

数据来源: NRC