23 8 



BACTERIA IN RELATION TO PLANT DISEASES. 



('95). THUMM, K. Beitrage zur Biologic der fluor- 

 escirenden Bakterien. Arbeiten aus dem 

 Bak't. Inst. der Tec'hnischen Hoohschule zu 

 Carlsruhe, Bd. i, 1895, pp. 291-377. 



The following summary of the most important results 

 is introduced in extenso, owing to the difficulty of pro- 

 curing the original paper : 



1. All fluorescent bacteria show in alkaline gelatin, 

 first a sky-blue, later a moss-green fluorescence, and with 

 the latter a yellowing of the substratum. Old cultures, 

 with the exception of those of Bacillus fluorescens puti- 

 dus, are orange-red, with a dark -green fluorescence. 



2. All these colors are due to one yellow pigment, a 

 concentrated watery solution of which is orange yellow, 

 a dilute one yellow. Both fluids are blue fluorescent, but, 

 upon the addition of an alkali, become, according to the 

 concentration, dark-green or moss-green fluorescent. 



3. All species produce the same pigment. 



4. All are alkali formers. The production of ammonia 

 in many species is considerable, and it is due to the pres- 

 ence of this alkali that the blue fluorescence gives place 

 to the green. 



5. The view of Naegeli, I^edderhose, and Kunz of the 

 formation of a leuco-pigment, and their attempt to trace 

 back the different colorings to oxidation phenomena, 

 has not been confirmed. 



6. Bacillus pyocyaneus Ernst, contrary to the view of 

 the other investigators, forms only one pigment. 



7. Ill potato cultures and on acid gelatin, the same col- 

 oring matter is produced as in alkaline media. The 

 green fluorescence is, in every case, caused by the action 

 of the ammonia. 



8. The a. aud forms of Bacillus pyocyaueus differ only 

 by the amount of ammonia produced not by a difference 

 in the pigment termed. The a form is a good, the j3 form 

 a poor alkali producer. When ammonia is added to a cul- 

 ture of the ft form, it resembles a culture of the a form. 



9. When an acid producer and a fluorescent form are 

 grown together in the same culture, the yellow pigment 

 appears normally, but there is no fluorescence. 



10. All species have the power of oxidizing grape sugar 

 with the production of an acid. The ammonia formed 

 later neutralizes this. 



11. The addition of sodium formate to the ordinary 

 nutrient gelatin causes an increased ammonia produc- 

 tion, 



12. In hydrochinon gelatin all species produce a brown- 

 ish-red color, due to the action of ammonia on the hydro- 

 chinon. This may, under certain circumstances, be used 

 as a test for ammonia. 



13. The behavior of the different species in media con- 

 taining different organic substances is so characteristic 

 that it may serve as a valuable means of differentiating 

 related species. Ammonium succinate, or asparagin, 

 affords good nourishment for all species. 



14. According to the source of the carbon or nitrogen, 

 the same organism is an abundant or scanty alkali pro- 

 ducer; e.g., Bacillus pyocyaneus Ernst is a poor alkali 

 former in nutrient gelatin, but a good one in ammonium 

 succinate. 



15. Each organism shows manifestations of life only 

 when it comes in contact with the oxygen of the air. 

 Hence, only there do we find pigment and formation of 

 ammonia. 



16. For the formation of the pigment, calcium chloride 

 is entirely unessential, but magnesium sulfate and potas- 

 itim phosphate are of the greatest importance. Gessard's 

 view, that only phosphoric acid is absolutely necessary, 

 is erroneous, nor may it ever be concluded that absence of 

 fluorescence it due to absence of phosfates. 



17. The substitution of calcium for magnesium, and 

 vice versa, does not influence the development of the 

 different species, but in the formation of the pigment, 

 calcium can not take the place of magnesium. 



18. The blue color of a fluid culture of Bacillus pyocy- 

 aneus, in the absence of phosphoric acid, is nevercaused 

 by pyocyanin, as Gessard assumed, but is referable only 

 to refraction phenomena. 



19. The least amount of potassium phosfate or mag- 

 nesium sulfate is sufficient for the formation of the fluor- 

 escent pigment. Where, in such nutrient solutions, 

 mostly blue fluorescence is to be observed, there has been 

 a decreased amount of ammonia produced because of the 

 small supply of nutrient salts in the solution. 



20. Bacterium syncyaneum has the power of forming 

 two pigments, a fluorescent and a steel-blue one. The 

 former agrees with that of the other fluorescent species. 

 The latter varies from steel-blue to brownish black, ac- 

 cording to the reaction of the medium. 



21. The fluorescence of the form of Bacterium syu- 

 cyaneum may be produced by cultivating it in ammonium 

 lactate and transferring to nutrient gelatin. 



('96). BIEL, WILHELM. Ueber einen schwarzes Pig- 

 nientbildenden Kartoffelbacillus. Centralb. 

 f. Bakt., 2 Abt., Bd. n, 1896, pp. 137-140. 

 ('96). SCHEURLEN. Geschichtliche und experiment- 

 elle Studien tiber den Prodigiosus. Archiv. 

 f. Hyg., 1896, Bd. xxvi, pp. 1-31. 

 ('96). GORINI, C. Ueber die schwarzen pigment - 

 ibildenden Bakterien. Centralb. f. Bakt., i 

 Abt., Bd. xx, 1896, p. 94. 



('97). EWART, A. J. Bacteria with asshnilatory pig- 

 ments, found in the tropics. Annals of 

 Botany, vol. xi, 1897, pp. 486-487. 

 Author found seven greenish bacteria in water at Buit- 

 enzorg, Java, showing a faint evolution of oxygen when 

 exposed to light. These were B. chlorinum and Strepto- 

 coccus varians, two forms closely resembling van Tieg- 

 heni's B. virens and Bact. viride; another large bacillus, 

 somewhat resembling van Tieghem's B. vireus, and two 

 Spirilla. The red Bacterium photometricum, which is 

 common in Java, gives, on treatment with hot alcohol 

 and extraction with benzine, a green dye which seems to 

 be identical with chlorophyll. 



('97). THIRY, G. Contribution a 1'etude du poly- 

 chromisme bacterien. Bacille et Cladothrix 

 polychromes; cristaux colores. Arch, de 

 physiol., 1897, No. 2, pp. 284-288. 



('97). NEUMANN, RUDOLF. Studien iiber die Varia- 

 ibilitat der Farbstofifbildung bei Mikrococcus 

 pyogenes a aureus ( Staphylococcus pyo- 

 genes aureus) und einigen anderen Spalt- 

 pilzen. Arch, f. Hyg., Bd. xxx, 1897, pp. 

 1-31. i table. 



" Die eiue Race kann also aus der anderen entstehen 

 und in eine andere iibergefiihrt werdeu." 



('98). 



('98). 

 ('98). 



('99). 



('99). 



('99). 



WARD, H. MARSHALL. A violet bacillus from 

 the River Thames. Annals of Botany, vol xn, 

 1898, pp. 59-74. One double plate in color. 



NIEDERKORN. See xv. 



RUZICKA. See xv. 



JORDAN, EDWIN O. The production of fluores- 

 cent pigment by bacteria. Botanical Gazette, 

 vol. xxvn, pp. 19-36, 1899. 



JORDAN, E. O. Bacillus pyocyaneus and its 

 pigments. Jour. Exper. Med., vol. iv, Nos. 

 5 and 6, 1899, pp. 627-647. ' 



BOLAND, G. W. Ueber Pyocyanin den Wauen 

 Farbstoff des Bacillus pyocyaneus. Centralb. 

 1 Bakt., xxv Bd., 1899, pp. 897-902, with i 

 curve. 

 Very probably B. pyocyaneus forms two pigments. 



('oo). THIRY, GEORGES. Bacille polychrome et Acti- 

 nomyces mordore. Recherches biologiques 

 sur lee bacteries bleues et violettes. Poly- 

 chromisme. Corps bacteriens t cristaux 

 colores. Matiere colorante cristallisee. 

 Travaux du lab. dMiyg. et de 1'inst. serothe- 

 rapique de 1'Univer. de Nancy. Paris, J. B. 

 Balliere et fils, 1900, pp. vm, 154, 7 plates. 

 Contains also a bibliography of 141 titles on pigment- 

 forming bacteria. 



('oo). KUNTZE, W. Ein Beitrag zur Kenntnis der 

 Bedingungen der Farbstoffbildung des 

 Bacillus prodigiosus. Zeitschr. f. Hyg., Bd. 

 xxxiv, Hft. i, 1900, pp. 169-184. Rev. in Cen- 

 tralb. f. Bakt, xxvin Bd., 1900, pp. 602-604. 



With a solution made up of 100 parts pure water, i to 2 

 asparagin, 2 to 4 c. p grape sugar, and 0.2 dipotassium 

 phosphate, the author obtained a fairly good growth of 

 B. prodigiosus without color. With the same solution 

 and a grape sugar not quite pure, there was always a 

 formation of pigment. The white bacteria became pig- 

 mented in a few hours on potato, or on adding a trace of 

 (o.ooi ) of MgSO4. This substance contaminated the sugar 

 first used. 



