Gelatinase Activity byMarine Fungi

PISANO, M.A.(St. John's University, Jamaica, N.Y.), J.A. MIHALIK, ANDG.R.CATALANO. Gelatinase activity bymarine fungi. Appl. Microbiol. 12:470-474. 1964.-Gelatinase activity wasdetectable intheculture filtrates of13of14species ofmarine fungi tested. Thefungi weregrown under conditions ofsubmerged culture inamediumconsisting ofcornmeal, soybean meal, and CaCO3. Thedegree ofenzymatic activity didnotnecessarily correlate withtheaminonitrogen content ofthefiltrates. Eight ofthefiltrates contained measurable quantities ofglutamic acid andalanine. Highest levels ofgelatinase wereobtained inthe culture filtrates ofHalosphaeria mediosetigera. Increasing the cornmealconcentration ofthemediumresulted inevengreater production ofgelatinase byH.mediosetigera, whereas amino acid yields wereenhanced byhigher concentrations ofsoybean meal.Supplementation ofthehighcornmealmediumwith either amineral mixture ordistillers' solubles brought about a faster rateofproduction ofgelatinase and,inthecaseofthe distillers' solubles, asignificantly higher level ofenzyme, aswell. Inrecent years, thenumberofpublications dealing with fungi isolated frommarine habitats hasbeensteadily increasing. Despite this fact, however, theoverall litera- tureaccumulated issignificantly less thanthatwhichis available forfungi fromother locales, suchasterrestrial environments. Relatively fewspecies ofmarine micro- organisms havebeentheobject ofdetailed investigations. Consequently, itisnotsurprising tofind that only asmall amountofattention hasbeendirected towards investiga- ionsofthequalitative orquantitative aspects, orboth, ofenzymeproduction bythese microorganisms. Reports suchasthose ofKriss, Mishustina, andZemtsova (1962) andBrisou andVargues (1963) indicate thatproteolysis is notuncommon amongbacteria obtained frommarine en- vironments. H6hnk(1953) demonstrated thatmarine fungi also werecapable ofattacking protein substrates. Moststudies oftheenzymatic activities ofmarine fungi, however, havedealt withtheir cellulolytic potential. More- over, qualitative rather thanquantitative aspects have beenpresented. Meyers andReynolds (1959), intheir study ofcellulose decomposition bymarine fungi, stressed thatthequantitative approach isessential toacomplete understanding ofthedynamics ofmarine fungi aswell as their contribution tomarine biology. Itwould appear that thesameapproach isrequired toevaluate fully thepossible contributions ofmarine fungal species tothefield ofin- 1Present address: FortDetrick, Frederick, Md. dustrial microbiology, especially withregard totheelab- oration ofproteolytic enzymes. Inthepresent study, 14species ofmarine fungi were investigated fortheproduction ofgelatinase undercon- ditions ofsubmerged culture. Theeffect ofmediumcompo- sition onenzymeproduction wasalsoinvestigated. The experiments devised included measurement ofamino nitrogen liberated during gelatin hydrolysis aswellas thedetermination ofaminoacids present intheculture filtrates.